taxonID	type	description	language	source
03AF87C4A63DFFB7AE8D685BFB028DB5.taxon	materials_examined	Material examined: 128 individuals in total (for details, see Supporting Information, Table S 1).	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A63DFFB7AE8D685BFB028DB5.taxon	description	Amended description: Large, body can exceed 500 μm (Table 1), with a poorly demarcated, blunt cephalic region and a large interval between legs III and IV (Fig. 5 A). Lacking a DABT (Figs 5 B, 6 A). The pharyngeal annulation simple in both PCM (Fig. 5 B) and SEM (Fig. 6 A, D, E), but occasional annular bifurcations present (Fig. 6 D, E). One band of teeth in the OCA (Fig. 6 B), not detectable in PCM (Fig. 5 B). Lateral porous areas in the walls of the buccal crown reduced and partly hidden under the apophyses for the insertion of stylet muscles (AISMs) (Fig. 6 C). Furca of the Hypsibius type (Fig. 6 F). Large pharyngeal apophyses. Three bar-shaped macroplacoids occasionally merged, but microplacoid and septulum always separate (Fig. 6 G). Claws of the Hypsibius type. Claw morphology (Figs 7, 8) largely conforming to that described by Dastych (1984), but in rare cases the posterior claw bases were not broadened (almost all occurring asymmetrically on one leg, Fig. 7 D) with respect to external claws I – III (Fig. 7 A – C). Some posterior claw bases so enlarged as to take almost a conical shape (Fig. 7 E). Claws of juveniles (probably hatchlings) delicate and with less well-developed indentation (Fig. 7 F). Rarely, this indentation may also be developed on the internal claw bases (Fig. 8 B). Internal bars visible under SEM as longitudinal thickenings adjacent to the internal claw bases (Fig. 8 A). Accessory points on claws IV more conspicuous and more widely divergent from the primary branches than on claws I – III (compare Fig. 8 A, B with C, D).	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A63DFFB6AEF96DEAFA6089A9.taxon	discussion	The phylogenetic position of Diphascon greveni Dastych, 1984 among the Diphasconinae (Fig. 2) further undermines the diagnosis of this group, which had previously been challenged by the inclusion of taxa lacking a DABT (Tumanov and Tsvetkova 2023, Zawierucha et al. 2023). Diphascon should group species with an apodeme according to its last broad diagnosis (Pilato 1987, Bertolani et al. 2014), although its morphology is diversified among species currently classified within this genus (Fig. 3). The type species of Diphascon, Diphascon chilenense Plate, 1888, and members of the Diphascon pingue group (Pilato and Binda 1997 / 8, 1999) have a disparate pharyngeal apparatus (short, rodshaped, or granular macroplacoids; Fig. 4) and claw morphology (minute claws with smooth bases and no bars) with respect to D. greveni, thus highlighting the artificial nature of the current definition of Diphascon Plate, 1888 (Tumanov and Tsvetkova 2023).	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A63FFFB4AC7069A7FE538C6D.taxon	type_taxon	Type species Diphascon scoticum Murray, 1905 in Murray (1905 a)	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A63FFFB5AC4F6A22FA91897C.taxon	materials_examined	Material examined: 21 individuals in total (for details, see Supporting Information, Table S 1). Comparative material: Scotland, Hill of Foudland (57 ° 23 ʹ 15 ″ N, 2 ° 39 ʹ 39 ″ W; 451 m a. s. l.), old slate quarry, lichen (Cladonia P. Browne) from soil, 1 November 2014, Blagden coll. (three specimens); Poland, Słowiński National Park (54 ° 42 ʹ 53 ″ N, 17 ° 13 ʹ 24 ″ E; 9 m a. s. l.), the Scots pine (Pinus sylvestris L.) forest, moss from soil, 3 September 2014, Morek coll. (one specimen).	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A63FFFB5AC4F6A22FA91897C.taxon	description	Amended description: Body medium-sized to large (Table 2), elongated and massive, of similar width over its entire length. Smaller specimens white, but larger brownish at least in the caudal part, often extending to the whole body (Fig. 9 A). Cuticle smooth, without pores, wrinkling, or granulation. Head blunt. Cribriform areas not visible under PCM. Legs short and stout. Eyes absent in live animals. Buccopharyngeal apparatus of the Adropion type (Fig. 9 B). The OCA not visible under PCM (Fig. 9 B). Furcae of the Hypsibius type. Pharyngeal apophyses absent (Fig. 9 B). Pharynx oval and broad. Macroplacoid length sequence 1 <2; all macroplacoids elongated and thin, with irregular, deeply serrated margins (Fig. 9 B – D). The second macroplacoid 2 – 2.5 times longer than the first, with a clearly swollen terminal part separated from the rest of the structure by a constriction (Fig. 9 C, D). Microplacoid small and of irregular shape (Fig. 9 B – D). Claws of the Hypsibius type, large and robust, with divergent accessory points. Claw septa usually clearly visible, dividing the claw into three portions (Fig. 9 E – G). Pseudolunulae weakly delineated and only sometimes visible at the base of the internal and anterior claws (Fig. 9 F, G). Cuticular bars absent; only slightly thickened edges of pulvini may be visible on the internal side of legs (Fig. 9 E). Remarks: A more detailed description of A. cf. belgicae was provided by Bernard (1977). Based on claw (stumpy and with distinct septa) and buccopharyngeal apparatus morphology, it is obvious that the specimens collected by Bernard in Michigan represented a similar species, but not A. belgicae s. s. They had three well-developed types of cuticular bars (internal, median, and anterior), as opposed to only pulvini present in A. belgicae. Thus, the American specimens must have belonged to a new species. Likewise, Fujiscon diphasconiellum Ito, 1991 is a different species owing to the dissimilar arrangement of bars; its current status should be Adropion diphasconiellum comb. nov. et stat. rev., by withdrawing it from an incorrect synonymy with A. belgicae (Maucci 1996) and pending a redescription. Dastych (1988) was the first to mention the brown colour in A. belgicae he collected in Poland. He also illustrated the conspicuous claw septa that are characteristic of the species.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A63FFFB5AC4F6A22FA91897C.taxon	etymology	Etymology: Named after the steamship Belgica, used in expeditions to Antarctic (1897 – 1899) and Arctic (1905, 1907 – 1909). A noun in genitive singular.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A63FFFB5AC4F6A22FA91897C.taxon	diagnosis	Differential diagnosis: There are only two other Adropion spp. with two macroplacoids in the pharynx: A. diphasconiellum comb. nov. et stat. rev. and Adropion gani (Sun et al., 2014) (a poorly diagnosed species with macroplacoids arranged rhomboidally; see below for the composition of the genus). Adropion belgicae has no cuticular bars, which distinguishes it sufficiently from A. diphasconiellum comb. nov. et stat. rev., which possesses three types of bars (internal, median, and anterior). Morphometric data would probably also be useful in separation of the two species; however, such data are unavailable owing to the outdated description of the former taxon. Because of general similarities in the morphology of the buccopharyngeal apparatus, A. belgicae canbemisidentifiedasamemberofthegenus Mesocrista Pilato, 1987 (Gąsiorek et al. 2016). Nevertheless, Mesocrista has a buccal tube that is wider than in Adropion (the thinnest buccal tube measured in Mesocrista had an external diameter of ~ 3.5 μm, vs. ~ 2.5 μm at its widest in A. belgicae), double annulation of the pharyngeal tube (single annulation in Adropion), and three types of cuticular bars at the claw bases (typically only the edges of external pulvini faintly observable in A. belgicae).	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A63EFFB9AEE36FCFFDC98E40.taxon	materials_examined	Material examined: 77 individuals in total (for details, see Supporting Information, Table S 1). Neotype material: Neotype and 49 specimens (slides GB. 043.01 – 09 and GB. 054.01 – 12) from Scotland, Drumoak, Drum Castle (57 ° 5 ʹ 42 ″ N, 2 ° 20 ʹ 16 ″ W; 114 m a. s. l.), leaf litter (mixed Quercus robur L. + Rhododendron L.) collected from soil, April 2016, Blagden coll., are deposited in the Institute of Zoology and Biomedical Research, Jagiellonian University, Kraków. Eight specimens (slides GB. 054.13 – 17; NHMD Catalogue number 1651660 – 4) are deposited in the Natural History Museum, University of Copenhagen, Denmark. Comparative material: Scotland, Scone Palace near Perth (56 ° 25 ʹ 21 ″ N, 3 ° 26 ʹ 16 ″ W; 28 m a. s. l.), rural vicinity, lichen from tree branch, 7 April 2016, Jakubczak coll. (three specimens); Battle Hill, Huntly (57 ° 27 ʹ N, 2 ° 47 ʹ W; ~ 130 m a. s. l.), rural vicinity, leaf litter from soil, April 2016, Blagden coll. (one specimen); Poland, Stubno, Starzawa Nature Reserve (49 ° 53 ʹ 18 ″ N, 23 ° 01 ʹ 44 ″ E; 201 m a. s. l.), peatbog, moss from peat, April 2014, Gąsiorek coll. (eight specimens).	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A63EFFB9AEE36FCFFDC98E40.taxon	description	Redescription: Body medium in size (Table 3), elongated and white, cuticle smooth, without pores or granulation (Fig. 10 A); however, in larger specimens (> 300 μm), the caudal end is wrinkled and can be brownish. Cribriform areas not visible under PCM. Legs short and plump. Eyes absent in live animals. Buccopharyngeal apparatus of the Adropion type (Fig. 10 A, B). The OCA not visible under PCM (Fig. 10 B). Furcae of the Hypsibius type, but with relatively elongate and divergent arms (Fig. 10 C). Pharyngeal tube annulated over its entire length, i. e. the last annuli extend to the ring-shaped thickening (Fig. 10 B, D); pharyngeal apophyses small (Fig. 10 D). Pharynx oval (Fig. 10 B; non-deformed pharynx length-to-width ratio: 1.6 – 2.0). Macroplacoid length sequence 2 <1 <3, all elongated and thin, with smooth margins. The third macroplacoid much longer than the first and second (Fig. 10 B, D) and with an evident subterminal constriction (Fig. 10 D). Microplacoid large, oval in PCM (Fig. 10 B), but clearly rod-like under SEM (Fig. 10 D). Claws of the Hypsibius type, large, with slightly widened bases and slightly protruding accessory points on the primary branches of claws I – III (Fig. 11 A, C). Claws IV with primary branches with more obvious accessory points and widened, calyx-like bases (Fig. 11 B, D). Pseudolunulae visible under the bases of the anterior claws IV (Fig. 11 B). Cuticular bars of three types present at the claw bases (all detectable solely under PCM): (i) small, roundish median bars between external and internal claws I – III (Fig. 11 A, filled arrowhead, often barely visible); (ii) large, internal oblique bars with irregular margins at the internal claw bases (Fig. 11 A, incised arrowhead), near to the internal pulvini; and (iii) long, thick posterior bars joining the bases of the anterior and posterior claws (Fig. 11 B, filled arrowhead). Remarks: Adropion scoticum ommatophorum (Thulin, 1911), described from Degerfors (Örebro, Sweden), has stouter claws, with short, broad bases and more curved secondary branches, and with the same arrangement of bars as described above for A. scoticum (Fig. 11 E – H). Moreover, the holotype of this subspecies has evident eyes, a condition unknown in populations of the type subspecies. Therefore, it is elevated to a species rank as A. ommatophorum comb. nov., pending a thorough redescription. In contrast, the Chinese subspecies Adropion scoticum qinlingensis (Li & Liu, 2005) does not exhibit traits that would allow its current taxonomic status to be ascertained (specimens are undistinguishable from the neotype series, because the shape of claw bases, i. e. narrow and calyx-like, presented by the authors as a differentiating trait, is the same for European and Asian individuals). As a result, we do not recognize the validity of the second subspecies. Consequently, all subspecies of A. scoticum are either elevated or supressed.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A63EFFB9AEE36FCFFDC98E40.taxon	etymology	Etymology: The name signifies a Scottish animal. An adjective in nominative singular.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A63EFFB9AEE36FCFFDC98E40.taxon	diagnosis	Differential diagnosis: The most similar Adropion species share three bar-shaped macroplacoids and a microplacoid in the pharynx, thus only two taxa must be compared with A. scoticum: Adropion marcusi (Rudescu, 1964) sp. dub. and A. ommatophorum comb. nov. (see also the key to Adropion spp.). Specifically, A. scoticum differs from: • Adropion marcusi sp. dub., known from Central – East Europe, by the presence of bars (three types of bars in A. scoticum vs. no bars in A. marcusi sp. dub.) and different macroplacoid formula (2 <1 <3 in A. scoticum vs. 1 ≤ 2 <3 in A. marcusi sp. dub.);	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A63EFFB9AEE36FCFFDC98E40.taxon	description	• Adropion ommatophorum comb. nov., described from Central Sweden, by a different claw morphology (see above) and the presence of eyes (absent in A. scoticum vs. present in A. ommatophorum comb. nov.).	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A632FFB9AC7168DDFB248FA7.taxon	discussion	The genus Adropion was inferred as polyphyletic by Bertolani et al. (2014). Gąsiorek and Michalczyk (2020) confirmed the non-monophyly of Adropion and established Guidettion (the latter having only three bar-like macroplacoids in the pharynx). However, the genus is still heterogeneous in terms of the number of macroplacoids: the majority of species exhibit three placoids, whereas there is a small group of species with only two macroplacoids, i. e. A. belgicae, A. diphasconiellum comb. nov. et stat. rev., and A. gani. The adoption of molecular phylogenetic methods in tardigrade research has shown that the number and shape of placoids in the pharynx is indicative of common ancestry (e. g. Gąsiorek et al. 2019, Guidetti et al. 2022). Thus, it is plausible that A. belgicae and A. diphasconiellum comb. nov. et stat. rev. are closely related and represent a separate evolutionary lineage. If reciprocal monophyly is confirmed molecularly, they should be erected as a new genus. However, A. gani is designated as nomen inquirendum, because having two rod-like macroplacoids arranged in parentheses (i. e. as in the members of the genus Pilatobius) it does not fit the current diagnosis of Adropion. Moreover, recently three species of Adropion, each with three placoids, were transferred to Kararehius (Zawierucha et al. 2023). Their systematic affinity remains to be verified genetically.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A632FFBEAC3569A7FA05880A.taxon	discussion	Remark: Adropion gani requires further investigation (see above) in order to ascribe it to the correct genus (i. e. a new genus or Pilatobius). Therefore, it is excluded from the key, together with A. marcusi sp. dub. Note that although D. greveni and D. mauccii Dastych & McInnes, 1996 belong within Diphasconinae (Tumanov and Tsvetkova 2023), they cannot be distinguished morphologically from Adropion based on the currently recognized taxonomic criteria and are thus included in the key.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A635FFBEAD956E67FD608887.taxon	type_taxon	Type species Diphascon prorsirostre Thulin, 1928	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A635FFA1AC5D6EFBFBF38DB2.taxon	materials_examined	Material examined: 48 individuals in total (for details, see Supporting Information, Table S 1). Neotype material: Neotype and 30 specimens (slides GB. 062.01 – 06) from Scotland, Little Oxen Craig, Bennachie (57 ° 17 ʹ 35 ″ N, 2 ° 33 ʹ 40 ″ W; 507 m a. s. l.), moss from rowan tree bark (Sorbus aucuparia L.), 5 October 2015, Blagden coll., are deposited in the Institute of Zoology and Biomedical Research, Jagiellonian University, Kraków. Seven specimens (slide GB. 062.07; NHMD Catalogue number 1651665) are deposited in the Natural History Museum, University of Copenhagen, Denmark. Comparative material: Scotland, Insch (57 ° 20 ʹ 32 ″ N, 2 ° 38 ʹ 44 ″ W; 268 m a. s. l.), rural vicinity, lichen (Cladonia) from rock, 19 December 2014, Blagden coll. (three specimens); Hill of Foudland (57 ° 23 ʹ 15 ″ N, 2 ° 39 ʹ 39 ″ W; 350 m a. s. l.), old slate quarry, moss from tree, 26 September 2015, Blagden coll. (10 specimens); Cabrach, Foot of The Buck (57 ° 18 ʹ 31 ″ N, 2 ° 57 ʹ 18 ″ W; 427 m a. s. l.), pine needles from soil, 26 September 2015, Blagden coll. (one specimen); Drum Castle, Drumoak (57 ° 05 ʹ 42 ″ N, 2 ° 20 ʹ 16 ″ W; 114 m a. s. l.), rural vicinity, leaf litter (Quercus robur) from soil, 5 September 2016, Blagden coll. (two specimens); Creag Meagaidh (56 ° 57 ʹ 03 ″ N, 4 ° 36 ʹ 09 ″ W; 1100 m a. s. l.), mountain grassland, lichen (Peltigera Willd.) from rock, 1 September 2016, Blagden coll. (seven specimens); Norway, RingsvassØya, Hansnes (69 ° 57 ʹ 37 ″ N, 19 ° 36 ʹ 23 ″ E; 3 m a. s. l.), forest, moss from soil, 3 Septmeber 2015, Hlebowicz coll. (six specimens); Poland, Kamienna Góra (50 ° 46 ʹ 39 ″ N, 16 ° 03 ʹ 22 ″ E; 490 m a. s. l.), urban park, moss from tree trunk, 5 September 2015, Przybycień coll. (six specimens).	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A635FFA1AC5D6EFBFBF38DB2.taxon	description	Redescription: Body small to medium-sized (Table 4), elongate and white; cuticle smooth, without pores, wrinkling or granulation (Fig. 12 A). Cribriform areas not visible under PCM. Legs short and plump. Eyes absent in live animals. Buccopharyngeal apparatus of the Adropion type (Figs 12 A, 13 A, B). The OCA invisible under PCM (Fig. 13 A), but visible in SEM as one row of conical teeth (Fig. 13 C). The AISMs flat, but rather narrow (Fig. 13 A, D). Furcae of the Hypsibius type (Fig. 13 E). Buccal tube transitions smoothly into the annulated pharyngeal tube (Fig. 13 A, B, F), with single, widely separated annuli (Fig. 13 F, G). In its posterior part, the pharyngeal tube is devoid of annulation (Fig. 13 H). Small pharyngeal apophyses present (Fig. 13 A, B, H). Pharynx oval (Fig. 13 A; non-deformed pharynx length-to-width ratio: 1.7 – 2.5). Macroplacoid length sequence 1 = 2 <3, all elongate and thin, with smooth margins. The third macroplacoid two times longer than the second (Fig. 13 H). Lacking microplacoid and septulum. Claws of the Hypsibius type, small, with slightly widened bases and slightly protruding accessory points on the primary branches (Fig. 14). The primary branches are much longer than the secondary branches. Secondary branches markedly curved. Pseudolunulae and cuticular bars at the claw bases absent (Fig. 14).	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A635FFA1AC5D6EFBFBF38DB2.taxon	etymology	Etymology: From Latin prorsus = having a forward projection, and rostrum = snout. The mouth opening is placed at the end of the snout, as a continuation of the main body axis in this species. An adjective in nominative singular.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A635FFA1AC5D6EFBFBF38DB2.taxon	diagnosis	Differential diagnosis: Depending on the position of a specimen (i. e. dorsoventral or lateral projection), the mouth opening may be described as terminally or more ventrally positioned in G. prorsirostre. In agreement with the observations and opinions of other tardigradologists (Cuénot 1932, Marcus 1936, Ramazzotti and Maucci 1983), we do not recognize the distinction between Guidettion arduifrons (Thulin, 1928), described based on animals collected in Lapland and Siberia, and G. prorsirostre (Fig. 12 B, C), thus we designate the former as nomen inquirendum. It is possible that G. arduifrons is a valid species, but the current morphological data prevent its identification. Guidettion carolae (Binda & Pilato, 1969) is morphologically identical to G. prorsirostre, as redescribed above, thus it is designated as synonym novum. Of the remaining species with only macroplacoids in the pharynx, the most similar to G. prorsirostre are Guidettion clavatum (Bartoš, 1935) and Guidettion modestum (Binda et al., 1984) (see the key to Guidettion spp.). However, G. clavatum exhibits granulated caudal cuticle and G. modestum lacks pharyngeal apophyses, characteristics sufficient to separate both taxa from G. prorsirostre. The recently described Guidettion vexatum (Pilato et al., 2017) does not appear to be sufficiently differentiated from G. prorsirostre. Its description was based on a small number of individuals, and several of the morphometric characters, in addition to the ‘ small dots on legs’ (as reported in the original description, i. e. a potential form of granulation), are not identifiable in any of the photomicrographs. These features, which were used to delimit G. vexatum from G. prorsirostre, can be questioned easily, owing to the increased accuracy of measurements provided in the present redescription of G. prorsirostre. Thus, we designate G. vexatum as nomen inquirendum, pending the verification of its validity.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A62CFFA7AF1D693DFA3B8CD7.taxon	discussion	Remark: Guidettion arduifrons nom. inq. is not included in the key, owing to the unavailability of traits differentiating it from G. prorsirostre.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A62CFFA7AC5D6B6BFD608D76.taxon	type_taxon	Type species Itaquascon umbellinae de Barros, 1939	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A62CFFA5ADCE6BD4FA268F5C.taxon	description	Itaquascon sp. nov.; Uganda; Gąsiorek and Michalczyk (2020). ZooBank registration: urn: lsid: zoobank. org: act: AD 578316 - D 601 - 4 F 5 A-B 00 D-F 37 B 94809 FE 9	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A62CFFA5ADCE6BD4FA268F5C.taxon	materials_examined	Material examined: 50 individuals in total (for details, see Supporting Information, Table S 1). Type material: Holotype and 26 paratypes (slides UG. 004.01 – 11) from Uganda, Kibaale District (0 ° 54 ʹ 55 ″ N, 31 ° 4 ʹ 44 ″ E; 1188 m a. s. l.), moss from tree trunk, 21 October 2014, Przybyłowicz coll., are deposited in the Institute of Zoology and Biomedical Research, Jagiellonian University, Kraków.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A62CFFA5ADCE6BD4FA268F5C.taxon	description	Description: Body medium-sized to large (Table 5), elongate and white, distinctly tapering in its anterior part (Fig. 15 A). Cuticle smooth, without pores, wrinkling or granulation. Cribriform areas not visible under PCM. Legs very short and plump, legs IV barely distinguishable from the posterior body end (Fig. 15 A). Eyes absent in live animals. Buccopharyngeal apparatus of the Itaquascon type, short (i. e. the pharynx reaches the level of the first pair of legs, Fig. 15). The OCA not visible under PCM (Fig. 15 B). Furcae of the Itaquascon type, with large and divergent apices. Stylet supports S-shaped, large and robust. Buccal-to-buccopharyngeal tube length ratio, pbf = 43 – 48 % (46 % on average). Pharyngeal apophyses absent (Fig. 15 B). Pharynx oval and narrow, devoid of cuticular ridges (i. e. reduced macroplacoids). Claws of the Hypsibius type, large and robust, with slightly protruding accessory points (Fig. 16). External and posterior claw bases long and rectangular in shape. External claw bases visibly concave. Anterior and posterior claw bases with weak / slight indentation (Fig. 16 B, D). Secondary claw branches short and bluntly terminated (Fig. 16). Pseudolunulae absent. Internal cuticular bars I – III present, long and thick, with those on the first pair of legs occasionally less evident (Figs 15 A, 16 A). Remarks: Claw bases with aberrant spines were found in only one specimen (Fig. 16 C, D). Some itaquasconin taxa were described on the basis of single specimens (e. g. Platicrista itaquasconoide Durante Pasa & Maucci, 1975), and the spines on their claw bases were used in delineating them. Therefore, we would like to note that this trait seems vague and might not be an appropriate criterion for species delineation.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A62CFFA5ADCE6BD4FA268F5C.taxon	etymology	Etymology: From the Latin serratum = indented, which highlights the peculiar character of the new species, i. e. claw IV bases with small teeth. An adjective in nominative singular.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A62CFFA5ADCE6BD4FA268F5C.taxon	diagnosis	Differential diagnosis: The only other species of Itaquascon having indented claw bases is I. mongolicus. However, I. serratulum differs from it in having the indentation only on claw IV bases (all claw bases indented in I. mongolicus). The general claw morphology is also different (more slender claws in I. serratulum vs. stout, massive claws in I. mongolicus; compare Fig. 16 A, B with Fig. 17 A), and the buccal tube constitutes less than half of the buccopharyngeal apparatus (pbf <50 % in I. serratulum vs. pbf> 50 % in I. mongolicus). Following Pilato and Lisi (2009), we use pbf = 50 % as the main discriminative criterion in the newly proposed key (see below). Therefore, it is only necessary to compare I. serratulum with the other member of the genus having pbf <50 % and cuticular bars on legs I – III, namely Itaquascon biserovi Pilato et al., 1999. The latter taxon, described from Central Africa, has all claws with smooth bases and S-shaped stylet supports inserted directly at the boundary between the buccal and pharyngeal tubes (pt = 100 %), whereas in I. serratulum stylet supports are positioned in a more anterior position, and never on the border between these structures (pt = 89.9 – 98.0 %).	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A62EFFABAE1169DEFA3A8CB6.taxon	discussion	Taxonomy of Itaquascon appears very challenging, mainly owing to the fact that, like Parascon and Raribius, the genus is rarely found and, if encountered, usually only in small numbers (i. e. fewer than five specimens). This rarity means that opportunities for extensive morphometric analysis and the drawing of robust conclusions based on intra- and interspecific variability of phenotypic traits are also limited and infrequent. Luckily, we obtained an enormously high number of individuals of I. serratulum (50 in total), which represents the largest number of specimens recorded in the literature so far (Węglarska isolated tens of individuals of R. pawlowskii from a single moss sample collected in the Polish Tatras, but unfortunately did not publish that interesting finding; B. Węglarska, pers. comm.). According to its original description, I. placophorum exhibits a dorsal papilla (Maucci 1973), a character never recorded in any other eutardigrade, making it a suspicious taxon. Thus, we examined the holotype of this species and found that the ‘ papilla’ is simply a conspicuous ventral cloacal fold. In a flattened individual, this ventral fold is visible through the translucent dorsal cuticle even when focusing on the dorsum (hence Maucci’s misinterpretation). It is not the first time that ventral structures have been interpreted as dorsal characters (see the case of the no longer valid ‘ Milnesium trispinosum ’ as discussed by Suzuki 2016). Internal bars on legs II – III of the I. placophorum holotype are thin but clearly visible (Fig. 17 B), like those in I. biserovi. Furthermore, we independently confirm the findings of Guidetti et al. (1999), who validated the presence of stylet supports in I. placophorum (Massa et al. 2021). There also seems to be a misunderstanding about the pattern of the pharyngeal tube annulation in the genus Itaquascon. Gąsiorek and Michalczyk (2020), based on high-quality SEM images, described the annulation in I. serratulum sp. nov. (Itaquascon sp. then) as ‘ complex, with annuli forking and merging irregularly’ (figs 4 i – j therein). In contrast, Massa et al. (2021), when interpreting the somewhat blurred SEM images of the buccal apparatuses of Itaquascon magnussoni Massa et al., 2021 and I. placophorum (figs 5 e – f and SM 6 therein), described the annulation in these species as an ‘ alternating hexagonal wire mesh’ and concluded that it is a different morphotype from that shown by Gąsiorek and Michalczyk (2020), thus suggesting that there is intrageneric variability. However, a careful comparison of the 2020 and 2021 microphotographs shows that the pattern in all analysed species is similar. In other words, the differences seem to be semantic, rather than morphological. Nevertheless, better-quality images of additional Itaquascon species are needed to allow more sound conclusions to be drawn. The other difference in our interpretations pertains to the pharyngeal structures. Unlike Massa et al. (2021), we do not regard the extremely thin cuticular ridges present in the pharynx of most Itaquascon species as typical macroplacoids. Consequently, we merge the amended diagnoses of the genus (Gąsiorek and Michalczyk 2020, Massa et al. 2021) into a single, unified diagnosis that addresses these disparate points of view: ‘ Dorsoposterior apodeme (drop-like thickening) between the buccal tube and the pharyngeal tube absent. S-shaped (sinusoidal) stylet supports. Pharynx elongated, oval or pyriform in shape, with placoids reduced to thin cuticular ridges or absent. Claws of the Hypsibius type; external claws with primary branches markedly longer than the secondary branches’. Taxonomic key to the genus Itaquascon Remark: Itaquascon enckelli (Mihelčič, 1971 / 72) and Itaquascon simplex (Mihelčič, 1971) have outdated descriptions that do not permit comparison with, or exclusion of other species. Thus, both are designated as nomen dubium and, consequently, not included in the key.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A620FFABAC426AAFFD1B8D31.taxon	type_taxon	Type species Diphascon angustatum Murray, 1905	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A620FFA8ADA46B08FBCB8830.taxon	materials_examined	Material examined: 49 individuals in total (for details, see Supporting Information, Table S 1). Neotype material: Neotype and 28 specimens (slides GB. 004.01 – 06, GB. 012.19 – 25, and GB. 058.01 – 10) from Scotland, Hill of Foudland (57 ° 23 ʹ 15 ″ N, 2 ° 39 ʹ 39 ″ W; 451 m a. s. l.), lichen (Cladonia) from soil in abandoned slate quarry, 1 November 2014, Blagden coll., and Scotland, Creag Meagaidh, Lochan a’ Choire (56 ° 57 ʹ 33 ″ N, 4 ° 34 ʹ 04 ″ W; 624 m a. s. l.), moss from rock in alpine grassland, 24 March 2016, Blagden coll., are deposited in the Institute of Zoology and Biomedical Research, Jagiellonian University, Kraków. Comparative material: Scotland, Gartly Forest, southern boundary (57 ° 23 ʹ 2 ″ N, 2 ° 42 ʹ 52 ″ W; 390 m a. s. l.), forest, lichen (Parmelia) from stone wall, 25 April 2015, Blagden coll. (five specimens); Oxen Craig, Bennachie, Oyne, Aberdeenshire (57 ° 17 ʹ 36 ″ N, 2 ° 33 ʹ 37 ″ W; 520 m a. s. l.), heather moor, soil from rock crevice, 20 September 2015, Blagden coll. (one specimen); Drum Castle, Drumoak (57 ° 05 ʹ 42 ″ N, 2 ° 20 ʹ 16 ″ W; 114 m a. s. l.), rural vicinity, leaf litter (Quercus robur) collected from soil, 5 September 2016, Blagden coll. (three specimens); Fort Augustus, Loch Ness (57 ° 08 ʹ 49 ″ N, 4 ° 40 ʹ 42 ″ W; 20 m a. s. l.), lake shore, moss from rock, 5 November 2015, Blagden coll. (two specimens).	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A620FFA8ADA46B08FBCB8830.taxon	description	Redescription: Body medium-sized to very large (Table 6), elongate and slightly narrowed in its anterior part (Fig. 18 A). Head blunt. Body white in smaller individuals, but brownish in the caudal part in large ones. Cuticle smooth, without pores or undulations, but with numerous irregular wrinkles intermingled with granulation in some individuals (Fig. 19). Cribriform areas not visible under PCM. Legs very short and plump; legs IV barely distinguishable from the posterior body end (Fig. 18 A). Eyes absent in live animals. Buccopharyngeal apparatus of the Platicrista type. The OCA absent (Fig. 18 B). Furcae of the Platicrista type, with branches pointing backwards. Pharyngeal apophyses absent; the pharyngeal tube is only slightly enlarged at its posterior end (Fig. 18 B). Pharynx oval and broad, with two thin macroplacoids, the second being at least two times longer than the first (1 <2). The macroplacoid margins are serrated (Fig. 18 B). Claws of the Hypsibius type, large and robust, with thick but barely divergent accessory points, acute and slender at their tips. Primary branches of internal and anterior claws particularly massive (Fig. 20). Anterior and posterior claw bases with irregular margins under PCM (Fig. 20 B); delicate indentation visible in SEM (Fig. 20 E). Pseudolunulae present and well developed (Fig. 20 A, B). Cuticular bars absent.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A620FFA8ADA46B08FBCB8830.taxon	etymology	Etymology: From the Latin angustatus = narrowed, most probably referring to the tendency, as described by Murray, of the animal to taper from legs III towards the anterior end of the body. An adjective in nominative singular.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A620FFA8ADA46B08FBCB8830.taxon	diagnosis	Differential diagnosis: All species of Platicrista that also lack cuticular bars on their legs are compared with P. angustata, as follows: • P. angustata differs from P. aluna (Lisi et al., 2019) by the absence of striation of the buccal tube; • P. angustata differs from P. carpathica sp. nov. by the absence of poorly developed indentation on all claw bases (compare Fig. 20 A, B with Fig. 25 B, C); • P. angustata differs from P. horribilis by the presence of smooth pseudolunulae (compare Figs 20 B and 27 D); • P. angustata differs from P. nivea sp. nov. by the presence of poorly developed indentation of claw IV bases (compare Figs 20 B and 28).	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A623FFA9AE006E25FB4A8DBA.taxon	description	ZooBank registration: urn: lsid: zoobank. org: act: 08931145 - 78 C 1 - 439 F- 85 DD- 2 A 48 C 3 CA 516 B	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A623FFA9AE006E25FB4A8DBA.taxon	materials_examined	Material examined: 10 individuals in total (for details, see Supporting Information, Table S 1). Type material: Holotype (slide MY. 100.01) and eight paratypes (slides MY. 090.01, MY. 091.02, MY. 100.01, and MY. 826.04) from Malaysia, Borneo, Sarawak, Gunung Mulu, The Main Trail (4 ° 02 ʹ N, 114 ° 48 ʹ E; ~ 60 m a. s. l.), moss from tree trunk in a primary rainforest, 27 July 2016, Gąsiorek coll., and Malaysia, Borneo, Sarawak, Bako Peninsula (1 ° 43 ″ 16 ‘ N, 110 ° 27 ʹ 39 ″ E; 107 m a. s. l.), moss from soil and tree trunk in a primary rainforest, 5 August 2017, Gąsiorek & Oczkowski coll., are deposited in the Institute of Zoology and Biomedical Research, Jagiellonian University, Kraków.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A623FFA9AE006E25FB4A8DBA.taxon	description	Description: Body white and elongate (Table 7), with blunt cephalic part (Fig. 21 A, B). Cuticle smooth, without pores, wrinkling or granulation. Cribriform areas not visible under PCM. Legs short, and even legs IV poorly delimited from the caudal body end. Eyes absent in unmounted animals. Buccopharyngeal apparatus of the Platicrista type (Fig. 21 B): OCA not visible under PCM, annulated pharyngeal tube shorter than rigid buccal tube, both being moderately wide; stylet supports embedded anteriorly on the buccal tube; furcae of the Platicrista type (cochlear); pharyngeal apophyses absent; pharynx oval, with two bar-like macroplacoids: the first distinctly shorter than the second (1 <2). Claws of the Hypsibius type, delicate and slender (Fig. 21 C). Accessory points not discernible on the primary branches of the external claws, but identifiable on the primary branches of the internal claws and only slightly separated from them. Septa between claw parts absent. Pseudolunulae absent. Median and posterior cuticular bars present (Fig. 21 A, C).	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A623FFA9AE006E25FB4A8DBA.taxon	etymology	Etymology: The name signifies the terra typica. An adjective in nominative singular.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A623FFA9AE006E25FB4A8DBA.taxon	diagnosis	Differential diagnosis: There are three congeneric species with cuticular bars on their legs: Platicrista brunsoni Miller and J. D. Miller, 2021, Platicrista cheleusis Kathman, 1990, and Platicrista ramsayi Marley, 2006. Platicrista borneensis can be differentiated from them based on: • P. brunsoni, the presence of median bars (present in P. borneensis vs. absent in P. brunsoni), the presence of polygonal sculpturing on the dorsum (absent in P. borneensis vs. present in P. brunsoni), and the presence of indentation on the base of claws IV (absent in P. borneensis vs. present in P. brunsoni); • P. cheleusis, the presence of median bars (present in P. borneensis vs. absent in P. cheleusis), and the presence of polygonal sculpturing on the dorsum (absent in P. borneensis vs. present in P. cheleusis); • P. ramsayi, the presence of median bars (present in P. borneensis vs. absent in P. ramsayi).	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A625FFAEAD8568EBFA928C96.taxon	materials_examined	Material examined: Two individuals in total (originating from northern Wyoming; loaned by courtesy of Harry Meyer).	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A625FFAEAD8568EBFA928C96.taxon	description	Amended description: Buccopharyngeal apparatus of the Platicrista type (Fig. 22 A): OCA not visible under PCM; simple pharyngeal annulation composed of tightly arranged single annuli; stylet supports inserted at the junction between the buccal and pharyngeal tubes; furcae of the Platicrista type (cochlear); pharyngeal apophyses not visible; pharynx oval, with two bar-like macroplacoids: the first much shorter than the second (1 <2). Claws massive, of the Hypsibius type (Fig. 22 B – D). Accessory points divergent only on the primary branches of the posterior claws (Fig. 22 D). Septa between claw parts absent. Pseudolunulae present at the internal and anterior claw bases. Irregular granulation on legs IV. Internal cuticular bars II – III with irregular margins (Fig. 22 C). Internal, anterior, and posterior claw bases delicately indented (Fig. 22 B – D). Basal portion of the posterior claws greatly broadened (Fig. 22 D). Dorsal cuticle with large polygonal granulation that extends to the lateral body parts (including legs). Granulation is most distinct in the cephalic (Fig. 23 A) to median and more caudal portions of the cuticle (Fig. 23 B). However, polygons may merge at the level of legs II – III, and form striae (Fig. 23 C). Polygons are different in shape in the caudalmost body portion, being more convex and irregular in shape (Fig. 23 D). Cribriform areas not visible under PCM.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A625FFAEAD8568EBFA928C96.taxon	discussion	Remarks: The original description contained several errors. The buccal tube width should not have been measured, at least not in the holotype, because it is evident from the photograph that the buccopharyngeal tube had collapsed (Miller and Miller 2021: fig. 2 B). This occurs frequently during mounting of Platicrista, Astatumen, and Itaquascon specimens on permanent slides (P. Gąsiorek, pers. obs.) and might be related to their shared similarities in the ultrastructure of the apparatus. The claws of P. brunsoni are of the Hypsibius type, not the Isohypsibius type. Finally, the dorsal sculpturing is not uniform across the dorsum, because the caudalmost polygonal tubercles are disparate in form. This makes P. brunsoni similar to P. cheleusis.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A625FFACAEF76AEFFBDE8C07.taxon	description	ZooBank registration: urn: lsid: zoobank. org: act: 4 D 82 EEA 5 - 92 A 6 - 4061 - A 43 E-F 4 C 09 B 97 F 307	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A625FFACAEF76AEFFBDE8C07.taxon	materials_examined	Material examined: 24 individuals in total (for details, see Supporting Information, Table S 1). Type material: Holotype (slide PL. 188.01) and 18 paratypes (slides PL. 088.01, PL. 188.02, PL. 201.01, PL. 245.01 – 3, PL. 249.01, PL. 287.03, PL. 296.01, and PL. 373.01) from Poland, various locales in the Tatra Mountains (Supporting Information, Table S 1), are deposited in the Institute of Zoology and Biomedical Research, Jagiellonian University, Kraków.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A625FFACAEF76AEFFBDE8C07.taxon	description	Description: Body massive (Table 8), white and elongate, with a blunt cephalic part (Fig. 24). Cuticle without pores, but with irregular wrinkling caudally and rudimentary granulation in the lateralmost portions of the dorsocaudal body part (Fig. 25). Cribriform areas not visible under PCM. Legs short and plump. Eyes absent in unmounted animals. Buccopharyngeal apparatus of the Platicrista type (Fig. 26 A): OCA not visible under PCM; annulation of the pharyngeal tube simple and comprising tightly merged annuli; stylet supports inserted at the junction between the buccal and pharyngeal tubes; furcae of the Platicrista type; pharyngeal apophyses absent; pharynx oval, with two bar-like macroplacoids: the first much shorter than the second (1 <2). Claws of the Hypsibius type, large and slender (Fig. 26 B – D). Accessory points tightly adjacent to primary branches of the external / posterior claws, but with tips divergent from the primary branches of the internal / anterior claws. A weakly developed indentation on all claw bases. Septa between claw parts absent. Pseudolunulae smooth. Cuticular bars absent. Pulvini visible when legs are oriented suitably (Fig. 26 C).	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A625FFACAEF76AEFFBDE8C07.taxon	etymology	Etymology: The name signifies terra typica. An adjective in nominative singular.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A625FFACAEF76AEFFBDE8C07.taxon	diagnosis	Differential diagnosis: There are four congeneric species characterized by an absence of cuticular bars on their legs and the presence of a poorly developed or entirely absent dorsal granulation: P. aluna, P. angustata, P. nivea and P. horribilis (granulation absent). Platicrista carpathica can be differentiated from them based on: • P. aluna, the absence of striation of the buccal tube; • P. angustata, see above; • P. horribilis, the indentation of the pseudolunulae under claws IV (absent in P. carpathica vs. present in P. horribilis) and the divergence of accessory points from the primary branches of the external and posterior claws (not divergent in P. carpathica vs. clearly divergent in P. horribilis; compare Figs 26 B – D and 27 B – D); • P. nivea, the presence and form of the caudal granulation (weakly developed only in the lateralmost part of caudal trunk in P. carpathica vs. strongly developed on the entire caudal trunk in P. nivea).	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A627FFADAE316A77FD9C8D4B.taxon	materials_examined	Material examined: 25 individuals in total (for details, see Supporting Information, Table S 1).	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A627FFADAE316A77FD9C8D4B.taxon	description	Amended description: The OCA not visible under PCM; simple pharyngeal annulation composed of tightly arranged single annuli; pharyngeal apophyses absent (Fig. 27 A). Large claws of the Hypsibius type (Fig. 27 B – D). Accessory points divergent from both primary and secondary branches of all claws. Pseudolunulae present, indented only on legs IV. Internal, anterior, and posterior claw bases with delicate indentations (Fig. 27 B – D). Cuticular bars absent.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A627FFADAE316A77FD9C8D4B.taxon	discussion	Remarks: The indentation of claw IV bases is not always as well developed as depicted in the original description (Kaczmarek and Michalczyk 2003). A more comprehensive morphometric dataset for the species is presented in Table 9.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A626FF92ADA16B38FA8C8DB6.taxon	description	ZooBank registration: urn: lsid: zoobank. org: act: 3988853 F- DDB 5 - 4217 - 8293 - 701 E 05 D 226 BD	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A626FF92ADA16B38FA8C8DB6.taxon	materials_examined	Material examined: Four individuals in total (for details, see Supporting Information, Table S 1). Type material: Holotype (slide TW. 006.07) from Taiwan, Snow Mountain (Xueshan), East Peak (24 ° 23 ʹ 18 ″ N, 121 ° 15 ʹ 39 ″ E; 3200 m a. s. l.), moss from rock in alpine grassland, 10 February 2020, Dreyer coll., and two paratypes (slides TW. 008.14 and TW. 008.15) from Taiwan, Snow Mountain (Xueshan), North Peak (24 ° 23 ʹ 51 ″ N, 121 ° 14 ʹ 04 ″ E; 3700 m a. s. l.), moss from rock in alpine grassland, 10 February 2020, Dreyer coll., are deposited in the Institute of Zoology and Biomedical Research, Jagiellonian University, Kraków.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A626FF92ADA16B38FA8C8DB6.taxon	description	Description: Body massive (Table 10), white and elongated, with blunt cephalic part (Fig. 28). Cuticle without pores, but with both irregular wrinkling and distinct, minute granulation in the caudal body part (Fig. 29). Cribriform areas identifiable under PCM (Fig. 29 A). Legs short and plump; legs IV poorly delimited from the trunk (Fig. 28). Eyes absent in unmounted animals. Buccopharyngeal apparatus of the Platicrista type (Fig. 30 A): OCA not visible under PCM; annulation of the pharyngeal tube simple (single bifurcations visible) and comprising tightly merged annuli; stylet supports embedded at the border between buccal and pharyngeal tube; furcae of the Platicrista type; pharyngeal apophyses absent; pharynx oval, with two bar-like macroplacoids: the first much shorter than the second one (1 <2). Claws of the Hypsibius type, large and slender (Figs 28, 30 B). Accessory points divergent from all claw branches. Indentation of claw bases absent. Septa between claw parts absent. Pseudolunulae present, but clearly discernible only under anterior claws (Fig. 28). Cuticular bars absent.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A626FF92ADA16B38FA8C8DB6.taxon	etymology	Etymology: From the Latin niveus = snowy, referring to the type locality in Snow Mountain (Taiwan). An adjective in nominative singular.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A626FF92ADA16B38FA8C8DB6.taxon	diagnosis	Differential diagnosis: There are two congeneric species with strong dorsal sculpturing: P. brunsoni and P. cheleusis. Platicrista nivea can be differentiated from them based on differences in the type of sculpturing (minute granules restricted to the caudal part in P. nivea vs. polygonal tubercles covering the entire dorsum in both species) and: • for P. brunsoni, the presence of internal bars II – III (absent in P. nivea vs. present in P. brunsoni); • for P. cheleusis, the presence of internal and median bars I – III and posterior bars (absent in P. nivea vs. present in P. cheleusis). Platicrista angustata and P. carpathica have a similar-looking dorsocaudal cuticle; see above for differentiation.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A618FF91AC726ABBFA3A8947.taxon	description	With body lengths exceeding 800 – 900 μm, several species of Platicrista are among the largest eutardigrades and are the largest hypsibiids. In light of this, the only species described from the tropics, P. borneensis, is evidently the most divergent in terms of adult body size (<< 500 μm) and buccopharyngeal tube, which is in agreement with its sister position with respect to all other Platicrista spp. (Fig. 2). The two Nearctic species, P. brunsoni and P. cheleusis, evolved a surprisingly similar type of dorsal sculpturing and thus might be closely related. We sequenced an additional, unnamed species from the Peruvian Andes that is a sister taxon of P. angustata (Fig. 2). It exhibits a weakly developed reticulum on the caudal body portion, not the irregular wrinkling present in P. angustata or P. carpathica. Taxonomic key to the genus Platicrista	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A618FF91AC726ABBFA3A8947.taxon	discussion	Remarks: Platicrista affine (Mihelčič, 1951) has an erroneous original description, because it is shown with macroplacoids forming a rhomb-like structure in the pharynx; such an arrangement remains unseen in the Itaquasconinae, which are characterized by pharyngeal structures arranged in parallel. We designate the species as objectively invalid, because it describes and depicts a mounting artefact or a morphological aberration and, consequently, we have not included it in the key. Platicrista itaquasconoide is assigned a nomen inquirendum status given that the description was shown to contain an error (the presence of a microplacoid was not confirmed; Marley 2006) and, with an example of I. serratulum, we show here that the presence of ‘ spurs’ on posterior claw bases is a morphological aberration, not a reliable taxonomic character. Finally, the claw IV bases of both P. itaquasconoide and P. angustata are indented. Consequently, given that the species lacks any morphological characteristics separating it from P. angustata, it is excluded from the key.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A61AFF91AD986FE9FD658E04.taxon	type_taxon	Type species Itaquascon pawlowskii Węglarska, 1973	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A61AFF97ADCF686BFBC28DB9.taxon	description	Raribius sp. nov.; Scotland; Gąsiorek and Michalczyk (2020). ZooBank registration: urn: lsid: zoobank. org: act: EB 412 AD 2 - 2 AD 0 - 4 F 57 - BA 97 - 07 D 3 D 287 D 33 B	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A61AFF97ADCF686BFBC28DB9.taxon	materials_examined	Material examined: Six individuals in total (for details, see Supporting Information, Table S 1). Type material: Holotype (slide GB. 043.10) and five paratypes (slides GB. 043.08 – 9, 11, and GB. 059.01 – 2) from Scotland, Drumoak, Drum Castle (57 ° 5 ʹ 42 ″ N, 2 ° 20 ʹ 16 ″ W, 114 m a. s. l.), leaf litter (mixed Quercus robur + Rhododendron) collected from soil, April and September 2016, Blagden coll., are deposited in the Institute of Zoology and Biomedical Research, Jagiellonian University, Kraków. Hologenophores were retrieved in a good condition and included in the type material owing to an overall paucity of individuals. Comparative material: Raribius pawlowskii; Poland, Polana pod Wołoszynem, Tatra Mountains, lower forest zone, mosses from rocks, February 1971, a paratype in the collection of the Zoological Museum, Jagiellonian University; Italy, vicinity of Rugolo, Treviso province, detailed data unspecified, collection of the Department of Life Sciences, University of Modena and Reggio Emilia.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A61AFF97ADCF686BFBC28DB9.taxon	description	Description: Body small (Table 11), elongate and slightly narrowed in its anterior part (Fig. 31 A). Head blunt. Body whitish to almost translucent. Cuticle smooth, without pores, wrinkling, or granulation. Cribriform areas not visible under PCM. Legs very short and weakly delimited from the trunk. Eyes absent in live animals. Buccopharyngeal apparatus of the Raribius type (Fig. 31 B). The OCA not visible under PCM. Furcae of the Itaquascon type, with triangular, large apices. Stylet supports S-shaped. Pharyngeal apophyses absent; instead, the pharyngeal tube is slightly enlarged at its posterior end. Pharynx almost perfectly round, with a single rectangular macroplacoid with smooth margins. Claws of the Hypsibius type, minute and slender, with accessory points not visible under PCM (Fig. 31 A, C). Pseudolunulae, cuticular bars, and septa absent.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A61AFF97ADCF686BFBC28DB9.taxon	etymology	Etymology: From the Latin minutissimus = the smallest. The species is one of the smallest eutardigrades. An adjective in nominative singular.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A61AFF97ADCF686BFBC28DB9.taxon	diagnosis	Differential diagnosis: Raribius minutissimus has short rectangular macroplacoids, whereas the pharynx is devoid of placoids in R. pawlowskii. No difference was detected in claw morphology (Fig. 32). Raribius globuliferus (Abe & Ito, 1994) has internal cuticular bars at the claw I – III bases and posterior bars (Guidetti et al. 1999), whereas both types of bars are absent in R. minutissimus.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A61EFF95ADB06B59FD098D44.taxon	type_taxon	Type species Diphascon bullatum Murray, 1905	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A61EFF9EADC16B3BFDB88F01.taxon	materials_examined	Material examined: Seven individuals in total (for details, see Supporting Information, Table S 1).	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A61EFF9EADC16B3BFDB88F01.taxon	description	Amended description: Eyes absent in live individuals. Body cylindrical (Fig. 33 A, B), with eight rows of poorly elevated, hemispherical gibbosities (VIII: 2 - 2 - 2 - 2 - 2 - 2 - 2 - 2) that are not covered with sculpturing (Fig. 33 A, C). The first row of gibbosities is at the level of legs I, whereas the last row is slightly divergent from the remainder and located at the base of leg IV (Fig. 33 A). Dorsal sculpturing in the form of irregular polygons (Fig. 33 C), extending to the lateralmost body portions including legs IV, but absent on legs I – III and venter (Fig. 33 B). Legs IV with sculpturing. Buccopharyngeal apparatus of the Pilatobius type (Fig. 33 B): OCA not visible under PCM; a large DABT at the border between the rigid buccal tube and annulated pharyngeal tube; furcae of the Hypsibius type; pharyngeal apophyses large and prominent; pharynx semicircular, with two bar-like macroplacoids: the first longer than the second (2 <1), and a septulum. The first macroplacoid with a slight anterior constriction, whereas the second macroplacoid with a subterminal constriction (Fig. 43 B). Claws of the Hypsibius type (Fig. 34). Primary branches of the external, anterior, and posterior claws with a swollen proximal part; light-refracting units absent. Accessory points divergent only on the primary branches of the posterior claws (Fig. 34 B). Pseudolunulae present. Internal cuticular bars I – III long and terminating at the pseudolunulae of the internal claws (Fig. 34 A). Claws IV with three types of short bars: (i) posterior; (ii) anterior, partly overlapping with pseudolunulae; and (iii) orthogonal (reported in specimens representing this or closely related species for the first time by Tumanov et al. 2022; Fig. 34 B).	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A61EFF9EADC16B3BFDB88F01.taxon	discussion	Remarks: We did not find a sufficient number of specimens to provide a modern redescription with DNA barcodes and morphometric data, but the factual qualitative characteristics provided above for animals collected in terra typica can serve as a starting point for the correct identification of this species. Specimens from Ireland (Blagden et al. 2020) and Russia (Tumanov et al. 2022) do not conform fully with the morphotype described herein because they exhibit sculpturing of the gibbosities, not detectable under LCM in specimens from Scotland and, consequently, are most likely to represent a closely related species. All three types of cuticular bars were first described by Dastych (1988) for Polish representatives of P. bullatus. He drew a reticulum on the gibbosities of these specimens, which is, however, absent in the Scottish population analysed here. There is a possibility that this character is variable and prone to observation errors; this could be clarified with a SEM examination. Dastych (1988) also hypothesized that Pilatobius patanei (Binda & Pilato, 1971) is synonymous with P. bullatus. Although the main criterion used to discriminate between the species (polygonal vs. supposedly granular sculpturing) was demonstrated to be invalid, the original description of P. patanei contains a vital diagnostic criterion: large granular eyes. Dastych (1988) questioned the utility of eyes in separating hypsibiid species, because he reported that they may be either absent or present in the same species, but our data indicate otherwise, i. e. that individuals belonging to one species either have or do not have eyes. Additionally, Tumanov et al. (2022) argued for the validity of P. patanei based on genetic differences between specimens identified as P. patanei (Bertolani et al. 2014) and P. bullatus (therein). We, therefore, keep P. bullatus and P. patanei as distinct taxa; nevertheless, this issue requires further analyses to dispel doubts that arose around P. patanei. In contrast, P. trachydorsatus is indistinguishable from P. bullatus and designated here as synonym novum.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A615FF9CAC4C6976FAFD8C41.taxon	materials_examined	Material examined: 158 individuals in total (for details, see Supporting Information, Table S 1). Neotype material: Neotype and 15 specimens (slides GB. 022.01 – 04) from Scotland, Aberdeenshire, Bennachie, Oxen Craig (57 ° 17 ʹ 36 ″ N, 2 ° 33 ʹ 37 ″ W; 520 m a. s. l.), mixed soil and leaf litter from bedrock, 20 September 2015, Blagden coll., are deposited in the Institute of Zoology and Biomedical Research, Jagiellonian University, Kraków; 11 specimens (slide GB. 022.05; NHMD Catalogue number 1651666) are deposited in the Natural History Museum, University of Copenhagen, Denmark.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A615FF9CAC4C6976FAFD8C41.taxon	description	Redescription: Body small to medium in size (Table 12), elongate and tapering anteriorly (Fig. 35 A), white. Cuticle intensively wrinkled starting from the level of the first leg pair to the caudal zone, with the most intense transverse wrinkles at the level of the third leg pair (Fig. 35 B). Cribriform areas (3 – 6) identifiable under PCM as large light ovals, particularly clearly visible in the wrinkled areas and in the sculptured caudal dorsum (Fig. 35 C). Dorsum strongly sculptured in its posterior part (Fig. 35 C); only rarely is this sculpture faint. Isolated sculptured areas are present on the dorsolateral cuticle up to the level of the second leg pair (Fig. 35 B). Sculpture composed of numerous irregular polygons. Legs long, devoid of sculpturing or pedal gibbosities (Fig. 35 A). Eyes always present in living animals, consisting of a few large granules merged into one eyespot (Fig. 36 A). Long buccopharyngeal apparatus of the Pilatobius type (Fig. 36 A, B). The OCA not visible under PCM (Fig. 36 A). Furcae of the Hypsibius type. The DABT large and round, lying directly above the transition zone between the buccal and very thin pharyngeal tubes, the latter with annulation of the Pilatobius type (Fig. 36 C). Annuli vanish ~ 2 μm before the pharyngeal apophyses (Fig. 36 D), which are large (Fig. 36 A, E). Pharynx circular (Fig. 36 A). Macroplacoid length sequence 2 <1, both with constrictions detectable under PCM (Fig. 36 A). The constriction in the first macroplacoid divides it into two roughly equal, oblique subparts. The constriction in the second macroplacoid is positioned more posteriorly, such that the second macroplacoid consists of a long part (two-thirds of the whole length) and a short, round terminal part (one-third of the whole length; Figs 36 E, 43 A). Septulum large, almost as long as the second macroplacoid. Claws of the Hypsibius type, rather stout, with characteristic light-refracting units at the basal portions of the primary branches (Fig. 37). Accessory points on claws I – III barely protruding, in contrast to those on claws IV (compare Fig. 37 A with 37 B). Primary branches of the posterior claws much longer in comparison to those of external claws (Fig. 37). Lacking pseudolunulae and cuticular bars.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A615FF9CAC4C6976FAFD8C41.taxon	etymology	Etymology: The name refers to the presence of granular eyes. Eyes are often large and do not dissolve in Hoyer’s medium. Murray (1906 b) decided to highlight this character, which still seems to be the correct decision, because in Pilatobiu s and its ‘ maternal’ genus, Diphascon, eyed species are not frequently found. An adjective in nominative singular.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A615FF9CAC4C6976FAFD8C41.taxon	diagnosis	Differential diagnosis: Unfortunately, descriptions of the vast majority of Pilatobius spp. are extremely laconic and do not allow for delineation between similar species. Pilatobius oculatus is most similar to Pilatobius rugocaudatus (Rodríguez Roda, 1952) nom. inq. within the oculatus group (with caudal sculpturing but lacking gibbosities), but they are currently indistinguishable owing to the lack of reliable morphometric or qualitative data (P. rugocaudatus is potentially a younger synonym of P. oculatus, and the vicinity of its type locality in the Pyrenees must be sampled to confirm this). Pilatobius oculatus is easily separated from other species because either they have the entire body sculptured or they have additional dorsal gibbosities (see the key below), and by the presence of light-refracting units at the basal parts of primary branches of external claws (the main difference with regard to P. opisthoglyptus and P. nuominensis Sun et al., 2021, which lack those structures).	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A615FF9CAC4C6976FAFD8C41.taxon	discussion	Remarks: Dastych (1988) underlined the importance of the primary branch light-refracting units in identifying this taxon. The subspecies Pilatobius oculatus alpius (Mihelčič, 1964) was designated as nomen dubium by Dastych (2015). We agree with this assessment, because the presence of pedal gibbosities on legs IV is unseen in pilatobiins. The second subspecies, Pilatobius oculatus canadensis (Murray, 1910) is insufficiently described, and the most important obscurity regarding this taxon is the absence of eyes, a feature always present in P. oculatus. This inconsistency led us to designating it as nomen dubium. We supress all subspecies of P. oculatus as taxonomically contentious.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A617FF82AE9A6A36FB5E8CB1.taxon	materials_examined	Material examined: 40 individuals in total (for details, see Supporting Information, Table S 1).	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A617FF82AE9A6A36FB5E8CB1.taxon	description	Description: Body small to medium in size (Table 13), corpulent (Fig. 38 A) and white. Cuticle uniformly sculptured on the entire dorsal surface by polygons of various sizes placed tightly adjacent to each other (Fig. 38 B, C); legs smooth. Cribriform areas not visible under PCM. Legs short, plump, and barely delimited from the trunk (Fig. 38 A). Eyes present in living animals, but usually quickly dissolving in Hoyer’s medium. Buccopharyngeal apparatus of the Pilatobius type, with a short pharyngeal tube (Fig. 38 D). The OCA not visible under PCM (Fig. 38 D). Furcae of the Hypsibius type. The DABT large and slightly elongate. Pharynx circular, with large pharyngeal apophyses. Macroplacoid length sequence 2 <1, the first with a delicate central constriction (Fig. 38 D). Septulum large, but clearly shorter than the second macroplacoid. Claws of the Hypsibius type, with external and internal claws of similar size (Fig. 39). Accessory points slightly divergent. All claw bases distinctly narrowed, but especially the anterior claws, which have calyx-like bases (Fig. 39 B, D). Pseudolunulae absent. Cuticular bars present and of three types: (i) internal, long thickenings terminating at the claw I – III bases (Fig. 39 A); (ii) anterior and (iii) posterior short rods (Fig. 39 B). All cuticular bars are undetectable in SEM (Fig. 39 C, D).	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A617FF82AE9A6A36FB5E8CB1.taxon	discussion	Remarks: Currently, there are two discriminative traits separating P. rugosus and P. iltisi (Schuster & Grigarick, 1965): the presence of deep transverse cuticular folds in P. iltisi and, according to Bartoš (1935) and Schuster and Grigarick (1965), the diameter of the polygonal granules that constitute the sculpturing increasing posteriorly in P. rugosus but not in P. iltisi. These cuticular folds could be a result of the preparation technique [see ‘ Remarks’ on P. sexbullatus (Ito, 1995)]. The dorsal sculpturing in our examined population does not agree with the original description but conforms to specimens identified as P. rugosus by Dastych (1988), thus indicating that resampling in the Turiec Basin is needed to verify the true morphotype of P. rugosus. General claw morphology is similar in P. rugosus, P. recamieri (Richters, 1911) (see Gąsiorek et al. 2017), and P. secchii (Bertolani & Rebecchi, 1996) nom. inq. (Fig. 42 E). Sculpture of P. ramazzottii (Robotti, 1970) is similar to that of P. rugosus; however, the polygons are larger and closer to each other (Fig. 42 F). Within the rugosus group (species with the entire dorsum covered by sculpturing and lacking dorsal gibbosities), four other species are gathered: P. granifer (Greven, 1972), P. latipes (Mihelčič, 1955) sp. dub., P. procerus (Pilato et al., 2014), and P. ziliense (Lisi et al., 2014). Of these, Dastych (2015) has already expressed doubts regarding the validity of P. latipes, with which we concur. P. granifer differs from P. rugosus by a completely dissimilar type of sculpturing [irregular small polygons in P. rugosus vs. large polygons resembling the caudal sculpturing of some species of the Ramazzottius oberhaeuseri (Doyère, 1840) complex, but clearly larger and with a conspicuous light centre in P. granifer; see Fig. 42 G]. Unfortunately, other differences cannot be given, because the description of P. granifer is insufficient, and the type material lost (H. Greven, pers. comm.). In our opinion, both P. procerus and P. ziliense are poorly differentiated from P. rugosus and require further investigation. P. nodulosus is distinguished from P. rugosus by its dissimilar type of sculpturing: very large polygons in the caudal zone (Fig. 42 D), with the size of the polygons subsequently decreasing anteriorly. The internal and anterior claws of the former species are also more massive (Fig. 42 C, D), rectangular bars are present below claws (Fig. 42 C, D), and claws IV have evident pseudolunulae (Fig. 42 D).	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A609FF86AE8B6A86FECE8D4D.taxon	materials_examined	Material examined: 13 individuals in total (for details, see Supporting Information, Table S 1). Comparative material: Russia, Baikal Lake, Olchon (53 ° 16 ʹ 08 ″ N, 107 ° 33 ʹ 05 ″ E; 525 m a. s. l.), shrubland, moss from soil, 14 September 2016, Barczyk coll. (one specimen). Amended description: Body small (Table 14) and corpulent (Fig. 40 A). A single median line of six large, poorly delineated hemispherical gibbosities: three at the level of legs I – III, two between legs I – II and II – III, and one in the segment behind the third leg pair (Fig. 40 A). Cuticle greatly sculptured on the entire dorsal surface by sub-round polygons of variable size: the largest present on the gibbosities and in the cephalic region, and the smallest on the lateral sides of the trunk (Fig. 40 A, B). Cribriform areas not visible under PCM. Legs short, plump, and barely delimited from the trunk (Fig. 40 A). Eyes present in living animals, but usually quickly dissolving in Hoyer’s medium. Buccopharyngeal apparatus of the Pilatobius type, with a short pharyngeal tube (Fig. 40 C). The OCA not visible under PCM. Furcae of the Hypsibius type. The DABT large; pharynx circular, with large pharyngeal apophyses (Fig. 40 C). Macroplacoid length sequence 2 <1, the first with delicate constriction at twofifths of its length. Septulum large, but clearly shorter than the second macroplacoid. Claws of the Hypsibius type, with very short basal portions; those of the external claws also slightly broadened (Fig. 41 A). The most remarkable are the bases of the posterior claws, which are extremely short, with margins evidently pointed upwards (Fig. 41 B). Primary branches of the internal and anterior claws much longer than the secondary branches (Fig. 41). Both branches of the external and posterior claws elongated. Accessory points barely divergent (Fig. 41). Pseudolunulae absent. Two types of cuticular bars present: (i) internal, long thickenings at the bases of claws IIII (Fig. 41 A); and (ii) posterior, short rods (Fig. 40 A); the latter may be absent (Fig. 41 B).	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A609FF86AE8B6A86FECE8D4D.taxon	discussion	Remarks: Specimens depicted by Dastych (1974) fit the description of P. sexbullatus. If their conspecificity is confirmed with DNA barcodes, all published records of this species (from Korea, Mongolia, and Russia, apart from the locus typicus in Japan) would strongly indicate an Eastern Palaearctic species. However, it must be noted that Dastych examined the types of P. iltisi, confirming the similarity of the Korean and American individuals [importantly, an unidentified Pilatobius species (Diphascon at that time) was recorded from the Polish Tatras by Dastych (1980), and P. iltisi was indicated as the taxon morphologically closest to that single specimen; the detailed drawing of that specimen shows a strong similarity to P. sexbullatus]. The dorsal cuticular thickenings of P. iltisi are likely to be an extremely flattened row of the dorsolateral gibbosities typically found in P. sexbullatus (slides made by Schuster and Grigarick usually contain strongly compressed tardigrades, which can cause artefacts; P. Gąsiorek, pers. obs.). Therefore, a putative synonymy of P. iltisi and P. sexbullatus (with a potential younger synonym being P. sexbullatus owing to an inadequate description of P. iltisi) should be considered. The zoogeographical implication of such action would be a single Holarctic species. All members of the bullatus group have paired dorsal gibbosities, thus they are easily distinguishable from P. sexbullatus with its autapomorphic condition of a single median line of gibbosities.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A60DFF8AAC626B39FA3C8AE9.taxon	description	The genus Pilatobius comprises species exclusively with two macroplacoids, arranged in parentheses, and a septulum in the pharynx. With the exception of the P. recamieri complex, Pilatobius members typically exhibit varying degrees of dorsal cuticular sculpturing (Figs 33 C, 35 C, 38 B, 40 B, 42 D, F, G; see below). The punctiform microplacoid mentioned in the original description of P. opisthoglyptus is most probably a mistake, because the interval between the second macroplacoid and the septulum seems too small to leave space for additional structures (Fig. 42 A). The claws of this species are stumpy, with short primary branches; those of the internal claws with a clear hump, and accessory points held tightly adjacent to the claw (Fig. 42 B). Two general morphotypes of the pharyngeal structures can be distinguished within Pilatobius: (i) short and robust macroplacoids, partly overlapping with the septulum (Fig. 43 A, B); and (ii) long and bar-like macroplacoids, followed by a clear gap between the septulum (Fig. 43 C – F). The first macroplacoid is typically subdivided at 40 – 50 % of its length by a deep constriction. The second has the constriction positioned (sub) terminally (Fig. 43 A – D, F). Only rarely are the constrictions poorly developed (Fig. 43 E). The morphometry of pharyngeal structures is, together with the existence of the cuticular sculpture, of crucial importance to the taxonomy of Pilatobius, thus redescriptions of ‘ old’ taxa and descriptions of new species should provide extensive measurements of these structures and their relative positions. Shortly after Pilatobius was established (Bertolani et al. 2014), it was revealed that the genus is paraphyletic, because Notahypsibius, which exhibits only a rigid buccal tube, is embedded among the pilatobiins (Tumanov 2020). The new phylogeny (Fig. 2) corroborates the previous findings, placing Notahypsibius as sister to the P. recamieri group, whereas the clade P. oculatus group + P. cf. bullatus is sister to that clade. In an attempt to make the systematics of Pilatobiinae closer to the natural state, we propose the division of the genus into four coherent morphological groups, in a similar manner to the way in which we approached the reorganization of Isohypsibius and Doryphoribius (Gąsiorek et al. 2019). Hence, the recamieri group comprises species with a smooth cuticle that lack dorsal gibbosities, whereas the bullatus group (= Pilatobius s. s. owing to the inclusion of P. bullatus, its type species) comprises species with a sculptured cuticle and dorsal gibbosities. Neither the oculatus group nor the rugosus group exhibit dorsolateral gibbosities; however, the cuticular sculpturing is developed differently in each of these species complexes: in the oculatus group, the cuticle is noticeably sculptured only caudally, although some small sculpturing may appear more anteriorly; whereas in the rugosus group, the cuticle is intensely sculptured over the whole dorsum. Two of these groups (the bullatus, oculatus, recamieri, and rugosus groups) are erected as new genera (see below) to reflect the phylogeny of Pilatobiinae (Fig. 2). Unfortunately, owing to our stringent selection criteria for the composition of the genetic dataset, we were forced to eliminate P. nodulosus (rugosus group), P. patanei (bullatus group), and P. ramazzottii (rugosus group) from our analysis, because only 18 S rRNA barcodes were available in GenBank. In agreement with the doubts raised by Ramazzotti and Maucci (1983), P. elongatus (Mihelčič, 1959) sp. dub. is designated as synonym novum of P. bullatus owing to the lack of separating characters. Given that the alleged rows of ‘ minor’ gibbosities in Pilatobius bisbullatus (Iharos, 1964) seem to be only folds of cuticle between otherwise typical gibbosities and are an artefact resulting from shrinkage of the specimens in the mounting medium, we designate the species as invalid. Other species (P. gerdae (Mihelčič, 1951) sp. dub., P. nonbullatus (Mihelčič, 1951) sp. dub. (both in bullatus group), P. latipes (Mihelčič, 1955) sp. dub. (rugosus group )) designated as dubious by Dastych (2015) are also considered as such and rejected in this paper.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A601FF8AAE2D6D5DFC478FFA.taxon	description	ZooBank registration: urn: lsid: zoobank. org: act: B 97 D 39 A 1 - 69 B 5 - 4 E 06 - 81 F 6 - F 671444 BFFC 6	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A601FF8AAE2D6D5DFC478FFA.taxon	diagnosis	Diagnosis: Cuticle distinctly sculptured in the caudal portion of the trunk; more anterior portions with a weaker sculpturing or smooth. Apophyses for the insertion of the stylet muscles (AISMs) in the shape of semilunar hooks. Buccal tube followed by a flexible annulated pharyngeal tube; the pharyngeal annulation is semi-complex (annuli single laterally and forking dorsoventrally). A DABT is present. There is a spherical pharynx with two macroplacoids and a septulum. Macroplacoids are arranged rhomboidally (◊). Claws of the Hypsibius type, i. e. asymmetrical both with respect to the sequence of primary and secondary branches (2 - 1 - 2 - 1) and with respect to their size, with external and posterior claws always evidently larger than the internal and anterior claws. Pseudolunulae below claws I – IV may be present; only basal cuticular bars below claws IV may be present, with the remaining types of bars absent.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A601FF8AAE2D6D5DFC478FFA.taxon	discussion	Composition: Degmion burti comb. nov., Degmion nodulosum comb. nov., Degmion nuominense comb. nov., Degmion oculatum comb. nov. (type species), Degmion opisthoglyptum comb. nov., and Degmion rugocaudatum comb. nov. et nom. inq.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A601FF8AAE2D6D5DFC478FFA.taxon	etymology	Etymology: The name honours Dr. Peter Degma, a renowned Slovakian tardigradologist and a great friend.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A601FF8AAE2D6D5DFC478FFA.taxon	diagnosis	Differential diagnosis: Within the Pilatobiinae, Degmion gen. nov., Pilatobius, and Fontourion gen. nov. possess a pharyngeal tube (absent in Notahypsibius) but: • Degmion gen. nov. has the dorsal sculpturing restricted to the caudal part of the trunk or the caudal sculpturing is much better developed than that found anteriorly and lacks dorsolateral gibbosities, whereas Pilatobius either exhibits gibbosities and / or its dorsal cuticle is uniformly sculptured throughout the trunk; • Degmion gen. nov. always exhibits an obvious caudal sculpturing, whereas the cuticle is smooth in Fontourion gen. nov.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A601FF8BAE396A6FFD2A8E72.taxon	description	ZooBank registration: urn: lsid: zoobank. org: act: ACDC 00 E 5 - 6 B 25 - 4823 - BFE 8 - 79 CEA 2 A 9457 E	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A601FF8BAE396A6FFD2A8E72.taxon	diagnosis	Diagnosis: Cuticle smooth. The AISMs are in the shape of semilunar hooks. Buccal tube is followed by a flexible annulated pharyngeal tube; the pharyngeal annulation is semi-complex (annuli single laterally and forking dorsoventrally). A DABT is present. There is a spherical pharynx, with two macroplacoids and a septulum. Macroplacoids are arranged rhomboidally (◊). Claws are of the Hypsibius type, i. e. asymmetrical both with respect to the sequence of primary and secondary branches (2 - 1 - 2 - 1) and with respect to their size, with external and posterior claws always evidently larger than the internal and anterior claws. Pseudolunulae below claws I – IV may be present; only internal and posterior cuticular bars may be present. Composition: Fontourion boreale comb. nov., Fontourion brevipes comb. nov., Fontourion glaciale comb. nov., Fontourion islandicum comb. nov., Fontourion recamieri comb. nov. (type species), and Fontourion secchii comb. nov. et nom. inq.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A601FF8BAE396A6FFD2A8E72.taxon	etymology	Etymology: The name honours Dr. Paulo Fontoura, an esteemed Portuguese tardigradologist.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A601FF8BAE396A6FFD2A8E72.taxon	diagnosis	Differential diagnosis: Within Pilatobiinae, Fontourion gen. nov., Degmion gen. nov., and Pilatobius possess a pharyngeal tube (absent in Notahypsibius) but: • Fontourion gen. nov. has a smooth dorsal cuticle and lacks dorsolateral gibbosities, whereas Pilatobius either exhibits gibbosities and / or its dorsal cuticle is uniformly sculptured throughout the trunk; • for the distinction with Degmion gen. nov., see above.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A601FF8BAE396A6FFD2A8E72.taxon	discussion	Remarks: Large pores used by Buda et al. (2018) to characterize F. islandicum comb. nov. are muscle attachment points that have no taxonomic value. With the exception of F. brevipes comb. nov., the species in the recamieri complex are extremely similar (Zawierucha et al. 2020), and we are of the opinion that the morphometric differences used to delineate them could result from discrepancies in the morphometry conducted by the various researchers. The species are clearly delineated genetically (Fig. 1), thus until proper redescriptions are performed, species identification in this lineage should rely on DNA barcoding.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A600FF88AC4D68C7FAE18FE4.taxon	diagnosis	Amended diagnosis: Cuticle uniformly sculptured throughout the dorsal part of trunk; dorsolateral gibbosities may be present. The AISMs in the shape of semilunar hooks. Buccal tube followed by a flexible annulated pharyngeal tube; the pharyngeal annulation is semi-complex (the annuli are single laterally and forking dorsoventrally). A DABT is present. A spherical pharynx with two macroplacoids and a septulum. Macroplacoids arranged rhomboidally (◊). Claws are of the Hypsibius type, i. e. asymmetrical both with respect to the sequence of primary and secondary branches (2 - 1 - 2 - 1) and with respect to their size, with external and posterior claws always evidently larger than the internal and anterior claws. Pseudolunulae below claws I – IV may be present; cuticular bars of various types (internal, anterior, posterior, and orthogonal) present. Composition: P. aculeatus (bullatus group), P. bullatus (bullatus group, type species), P. granifer (rugosus group), P. iltisi (rugosus group), P. patanei (bullatus group), P. procerus (rugosus group), P. ramazzottii (rugosus group), P. rugosus (rugosus group), P. sexbullatus (bullatus group), and P. ziliense (rugosus group).	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A600FF88AC4D68C7FAE18FE4.taxon	discussion	Remarks: We consider the genus Pilatobius as artificial (nonmonophyletic) in its present composition. Additional DNA data should contribute to disentangling its phylogenetic affinities, and the topology of the pilatobiin tree. Problems with hypsibiid classification This study provides redescriptions of some crucial hypsibiid species and descriptions of new species that were included in the paper devoted to hypsibiid phylogeny (Gąsiorek and Michalczyk 2020). We provide a good starting point for sound taxonomic research on the genera Adropion, Guidettion, and Platicrista, at the same time stressing that without a reliable redescription of Astatumen trinacriae from Sicily, a trustworthy species identification within that genus remains impossible. A higher-level classification of Hypsibiidae illustrates the conflict between the morphological vs. phylogenetic approaches to tardigrade systematics, which had been ripening over the last few years and has recently erupted independently in several contributions. Although the currently recognized four hypsibiid subfamilies (Pilato and Binda 2010, Bertolani et al. 2014) have been recovered independently as clades (Gąsiorek and Michalczyk 2020, Tumanov 2020, Tumanov and Tsvetkova 2023, Zawierucha et al. 2023), their current morphological diagnoses are meaningless owing to the erroneous inclusion of some taxonomic features within each clade (originally, Pilatobiinae were defined as having an elongated pharyngeal tube, Itaquasconinae – without the DABT, and Diphasconinae – as having macroplacoids in the pharynx; all these characteristics have recently been demonstrated as diagnostically questionable). Recently, Tumanov and Tsvetkova (2023) proposed that Itaquasconinae and Pilatobiinae should be elevated to the ranks of separate families within Hypsibioidea. However, in this paper, we have maintained the previous classification of broadly understood Hypsibiidae, for several reasons. The main arguments for dividing Hypsibiidae were their morphological heterogeneity and the lack of monophyly in the molecular analyses of Tumanov and Tsvetkova (2023). However, the first reason is highly subjective (we do not consider traditionally defined Hypsibiidae as more diverse than, e. g. Macrobiotidae), and the elevation of two of the subfamilies to the rank of families does not change the fact that none of the four hypsibiid groups has a coherent diagnosis. Moreover, neither Itaquasconinae nor Pilatobiinae differ consistently from the clade Diphasconinae + Hypsibiinae [Tumanov and Tsvetkova (2023) proposed a ‘ transfer’ of Diphasconinae to Hypsibiidae, which was redundant, because diphasconins had already been included in this family at that time] and between each other, which would justify the taxonomic elevation of their status. The lack of hypsibiid monophyly can be explained by the highly fragmented (e. g. only the 18 S rRNA marker available for some taxa), incomplete, and taxonomically biased (many unusual hypsibiid morphotypes are still not sequenced) genetic dataset at our disposal. In short, based on the available data, we do not recognize the validity of the proposal put forward by Tumanov and Tsvetkova (2023). Nevertheless, we do not exclude the possibility of such moves in the future. Currently, the evidence is simply not there. In concordance with Tumanov and Tsvetkova (2023), the presence of the DABT (= drop-like thickening sensu Guidetti et al. 2013 / drop-like apodeme sensu Tumanov and Tsvetkova 2023) can no longer serve as the main distinguishing criterion between Adropion and Diphascon (and, ipso facto, between Itaquasconinae and Diphasconinae). We revealed that this structure can take various forms, and it should be analysed under SEM to determine its shape accurately. In this regard, Dastych et al. (1990) have already noted that the straightforward distinction between the lack (Adropion) and presence (Diphascon) of an apodeme (Pilato 1987) is contravened by the slight thickening of the buccal tube wall in Diphascon higginsi Binda, 1971, Diphascon puniceum Jennings, 1976 in Jennings (1976 b), and D. sanae Dastych et al., 1990. The apodeme is reduced and flattened in D. higginsi (Fig. 2 A, B), which has contributed to confounding views regarding the affinity of the species (Ramazzotti and Maucci 1983, Pilato and Binda 1988). Furthermore, the apodeme in the D. pingue group is not a solid drop-shaped thickening, as it would appear in LCM. Instead, when observed in SEM, it is a pair of looped filaments with mostly empty lateral portions (possibly joined by one or more irregular cuticular septa in the middle; Fig. 3 C, D). As noted above, Tumanov (2020) described a remarkable case of paraphyly: the genus Notahypsibius, characterized by a hypothetically plesiomorphic rigid buccal tube (Gąsiorek and Michalczyk 2020), has been placed within Pilatobius, which exhibits an advanced, elongated posterior portion to its buccopharyngeal apparatus referred to as the pharyngeal tube (Bertolani et al. 2014). This topology is maintained in the new phylogeny presented herein (Fig. 2), which also includes several recently described taxa. The issue of the paraphyletic taxa in classification, which affects many tardigrade lineages, is a topic long discussed in both botany and zoology (Schwenk 1994, Brummitt 1996, Hörandl and Stuessy 2010). Putting aside the fact that a natural consequence of anacladogenesis is the presence of paraphyletic taxa, we are of the opinion that natural classification should aim at distinguishing onlymonophyletictaxa. Besidesthe Notahypsibius – Pilatobius case, which we resolve, in part, by establishing Degmion and Fontourion, a similar puzzling state is found in Hypsibiinae, in which Borealibius (Pilato et al. 2006) and Cryobiotus (Dastych 2019), i. e. genera with clear autapomorphic conditions, are probably (although genetic data are scarce) embedded within the ‘ plesiomorphic’ Hypsibius (see also Tumanov and Tsvetkova 2023). Hypsibius scabropygus Cuénot, 1929 is typically recovered as sister to all other hypsibiins and should be erected together with a few other Hypsibius species as a separate genus (Gąsiorek et al. 2018). An analogous problem was recently shown in Macrobiotidae, in which the strongly modified genus Xerobiotus (Bertolani & Biserov, 1996) is nested within Macrobiotus and thus should be considered a species group within Macrobiotus (Stec et al. 2021). We do not exclude the possibility that some of these taxa are only superficially artificial, because DNA sequences are lacking for the vast majority of species, and that the phyletic relationships might eventually turn out to be different from what we currently know, but this issue seems topical and requires further study. In fact, the only hypsibiid subfamily that seems well defined morphologically from the remaining clades are the Hypsibiinae, whose morphology of the buccopharyngeal apparatus includes plesiomorphic eutardigrade characters [a likely ancestral type, comprising only a rigid buccal tube and granular or bar-like macroplacoids without signs of thinning and forming single, thin and long macroplacoids typical of many itaquasconins and some diphasconins; however, see the alternative hypothesis postulated by Bertolani et al. (2014) and Tumanov (2020), according to which the presence of only the buccal tube within the buccopharyngeal apparatus is considered apomorphic]; and claws that are relatively homogeneous within Hypsibiidae (see Guil et al. 2013). This means, and is the main point of our criticism, that narrow definitions of newly erected supraspecific taxa, which focus on autapomorphies (always termed subjectively as ‘ strong’ or ‘ weak’) and neglect the topology of the evolutionary tree, will inevitably lead to creation of paraphyletic taxa characterized by advanced characters and nested among groups of a plesiomorphic nature (Fig. 44). Therefore, we advocate for the phylogenetic approach and the rule of reciprocal monophyly (Hennig 1966) in tardigrade systematics. The paraphyletic status of some tardigrade taxa is not the only problem affecting hypsibiid classification. The addition of A. tenue and Arctodiphascon wuyingensis (Sun et al., 2020) blurred the distinction between Diphasconinae and Itaquasconinae further (Tumanov and Tsvetkova 2023). This means that some Diphascon spp. with a DABT might, in fact, belong to the Itaquasconinae, ordinarily apodemeless (the apodeme is small and may be reduced in A. wuyingensis). The intricacy of this situation stems from the lack of a morphological apomorphy that would allow A. wuyingensis to be placed in a new genus (Arctodiphascon was erected with clear evidence of non-monophyly; Tumanov and Tsvetkova 2023). However, this discrepancy might be resolved when the species is studied in more detail, because Tumanov (2020) and Tumanov and Tsvetkova (2023) pointed out that traits previously neglected in hypsibiid taxonomy, such as ornamentation of eggs deposited in exuviae, might prove useful in monophyletic classification.	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
03AF87C4A600FF88AC4D68C7FAE18FE4.taxon	materials_examined	To sum up, the phylogenetic and morphological diversity of hypsibiids must be researched to a greater extent in order to define accurately the four main clades that are currently recognized as subfamilies. Based on our analyses, we postulate that the morphology of the DABT might bear an important evolutionary value. The morphological characterization of pedal bars, summarized in this paper, aims at unifying the anatomical terminology to aid taxonomic descriptions and comparisons. Integrative revisions of type species were, once again, demonstrated as pivotal to the decluttering of tardigrade classification. It appears that, in many instances, the evolutionary significance of particular phenotypic characters in tardigrade systematics is misunderstood. As a result, subjective assessments of morphology as the only basis for erection of new higher taxa, i. e. finding (‘ strong’) apomorphies, lead to the erection of taxa defined by characters (phenetic systematics), and not by factual evolutionary affinities (i. e. reciprocal monophyly; e. g. see de Queiroz and Gauthier 1990).	en	Gąsiorek, Piotr, Blagden, Brian, Morek, Witold, Michalczyk, Łukasz (2024): What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela). Zoological Journal of the Linnean Society 202 (1): 1-63, DOI: 10.1093/zoolinnean/zlad151, URL: http://dx.doi.org/10.1093/zoolinnean/zlad151
