taxonID	type	description	language	source
824287C5802AFF988B1FFAF3B3BDFCED.taxon	materials_examined	Type genus: Eurynotus Agassiz, 1833 – 1844. Included genera: Eurynotus Agassiz, 1833 – 1844, Styracopterus Traquair, 1890, Fouldenia White, 1927, Benedenius Traquair, 1878, Amphicentrum Young, 1866, Cheirodopsis Traquair, 1881, Paramesolepis Moy-Thomas & Bradley Dyne, 1938, Wardichthys Traquair, 1875, Proteurynotus Moy-Thomas & Bradley Dyne, 1938, Mesolepis Young, 1866. Diagnosis: Actinopterygians with tall rectangular trunk scales bearing central pointed pegs at least 50 % height of scale; jaw margins covered with thick ganoine and without visible teeth; premaxilla edentulous; dentary edentulous; maxillary dentition mesial to jaw margin and obscured laterally by dermal bone; palatal and mandibular tooth plates with denticles; maxilla with triangular posterior expanded portion and thick anterior ramus; mandible robust with acute symphysis in lateral aspect; snout blunt in lateral profile; preoperculum tall with horizontal pit line; suboperculum with anteroventral process; dorsal ridge scales prominent and acuminate, running from skull to dorsal fin origin; basal fulcra erect and pointed; median fins with longest fin ray more than fourth in position from leading edge; primary median fin lepidotrichia spine-like and without clear segments; fringing fulcra prominent, pointed, and overlapped distally on all fins. Symplesiomorphies: antorbitals absent; single median rostral; single nasal in contact with frontal and dermosphenotic; frontals longer than parietals; dermopterotic present; uninterrupted contact between preopercular and infraorbitals; supraorbitals absent; dermohyal present; single postcleithrum; axial lobe extending beyond caudal fin and axial fulcra with micromeric elliptical scales; epichordal fin present and distinct from caudal fin.	en	Sallan, Lauren Cole, Coates, Michael I. (2013): Styracopterid (Actinopterygii) ontogeny and the multiple origins of post-Hangenberg deep-bodied fishes. Zoological Journal of the Linnean Society 169 (1): 156-199, DOI: 10.1111/zoj.12054, URL: http://dx.doi.org/10.1111/zoj.12054
824287C5802AFF9889A3FC9CB211F9F0.taxon	materials_examined	Type genus: Styracopterus Traquair, 1890. Included genera: Styracopterus Traquair, 1890, Fouldenia White, 1927, Benedenius Traquair, 1878. Diagnosis (emended from Gardiner, 1985): Eurynotiform fishes with bands of smooth ganoine ornament on maxilla and dentary, parallel with jaw margins; contact between frontals and parietals v-shaped; nasal expanded ventrally, in contact with lachrymal; dermosphenotic mediolaterally broad with curved anterior process; cleithrum scythe-shaped with wide dorsal process; anal fin height greater than base length; pelvic fins with enlarged basal fulcra; axial lobe with distinct curvature; epichordal fin present; scales on axial lobe elliptical with longitudinal ganoine bands; axial basal fulcra with needle-shaped apex bearing paired dorsal ridges; lepidotrichia jointed regularly throughout length with short, plate-like segments; fringing fulcra paired on anterior margins of paired fins; fringing fulcra on distal portions of anal fin and caudal fin heavily overlapped and elliptical; sensory canals obscured by ornament in skull roof.	en	Sallan, Lauren Cole, Coates, Michael I. (2013): Styracopterid (Actinopterygii) ontogeny and the multiple origins of post-Hangenberg deep-bodied fishes. Zoological Journal of the Linnean Society 169 (1): 156-199, DOI: 10.1111/zoj.12054, URL: http://dx.doi.org/10.1111/zoj.12054
824287C5802AFF998983F972B573FC69.taxon	materials_examined	Type and only species: Styracopterus fulcratus (Traquair, 1881). Diagnosis (emended from Gardiner, 1985): Styracopterid eurynotiform fish with two smooth ganoine bands on jaw margins of maxilla and dentary; maxilla with right-triangle-shaped posterior expansion and pointed anterior ramus; dentary shallow with angled anterior margin; mandibular canal pores large; maxillary teeth large and fang-like with a visible collar marking acrodin caps; palatal tooth-plate denticles large, stout, and rounded; mandibular tooth plate denticles small and rectangular; premaxilla fused to rostral; frontals with sigmoidal lateral margin; parietals triangular with sigmoidal lateral margin; dermopterotic curved laterally; post-temporal broad; suspensorium near vertical; preoperculum vertical with straight margins; opercular rectangular; subopercular taller than opercular with straight posterior margin; broad patches and bands of smooth ganoine over pointed anterior ramus; flank scales tall with ornament of nested ridges dorsally and horizontal ridges ventrally; dorsal ridge scales with thick horizontal ornament; ventral ridge scales near skull; pectoral fin long and scythe-shaped with broad leading lepidotrichia bearing rectangular segments; pelvic fin small and triangular with single preceding basal fulcrum; anal fin subtriangular with straight posterior margin. Occurrence: Early Visean of Scotland.	en	Sallan, Lauren Cole, Coates, Michael I. (2013): Styracopterid (Actinopterygii) ontogeny and the multiple origins of post-Hangenberg deep-bodied fishes. Zoological Journal of the Linnean Society 169 (1): 156-199, DOI: 10.1111/zoj.12054, URL: http://dx.doi.org/10.1111/zoj.12054
824287C5802BFF8A8A9BFBE7B520F9B0.taxon	materials_examined	Holotype: GSE 5673 (M 146 e) and counterpart GSE 5672 (M 147 e), British Geological Survey, Edinburgh, Scotland, UK, incomplete articulated fish in part and counterpart showing the dorsal portion of the trunk, scales, dorsal fin, and shoulder series (estimated body length, EBL: 12 cm). Additional material: NHM P 1663, incomplete articulated fish in part with trunk, skull, paired and median fins (EBL: 8 cm); GSE 8731, incomplete articulated fish in part showing anterior two-thirds of animal, including skull (EBL: 8 cm); GSE 2136, incomplete articulated fish in part showing anterior third of animal, including skull (EBL: 16 cm); GSE 5663 (part) and GSE 5664 (counterpart), nearly complete articulated fish (EBL: 16 cm); NMS 1891.53.49, National Museums of Scotland, Edinburgh, Scotland, UK, incomplete articulated fish in part showing anterior half of animal (EBL: 11 + cm); NMS 1891.53.50 (part) and NMS 1891.53.51 (counterpart), incomplete articulated fish showing anterior half of animal (EBL: 11 + cm), GM 1902.85. md (part), Kelvingrove Art Gallery and Museums, Glasgow Museums, Glasgow, Scotland, UK, incomplete articulated fish showing anterior half of trunk and dermal jaws (EBL: 9 cm). Type locality and horizon: Tarras Waterfoot (Traquair, 1881), River Esk, Eskdale, Dumfriesshire, Scotland, UK. Calciferous Sandstone Series, Cementstone Group, Holkerian regional substage (339 – 337.5 Mya), early Visean Stage, Mississippian Subsystem, Early Carboniferous. Other localities and horizons: Glencartholm Volcanic Beds, Dumfriesshire, Scotland, UK. Calciferous Sandstone Series, Cementstone Group, Holkerian regional substage (339 – 337.5 Mya), early Visean Stage, Mississippian Subsystem, Early Carboniferous (Gardiner, 1985; Dineley & Metcalfe, 1999). Diagnosis (emended from Gardiner, 1985): As for genus. Remarks: Moy-Thomas (1937) placed species within the genus Fouldenia into the synonymy of the older taxon Styracopterus in his redescription of the latter genus. Gardiner (1985) subsequently lumped all designated Styracopterus species into Styracopterus fulcratus. However, a re-examination of specimens has shown that the characters used by Moy-Thomas (1937) and Gardiner (1985) are diagnostic of many genera within a more inclusive clade: the Eurynotiformes, as diagnosed above. There are in fact two distinct taxa, one being a Visean S. fulcratus and the other representing Tournaisian fish (see diagnoses and discussion). Thus, the original genus Fouldenia is resurrected, encompassing all specimens assigned to this taxon by White (1927) and subsequent workers, as well as individuals previously attributed to S. fulcratus originating from the sediments at the Foulden Fish Bed (Gardiner, 1985) and other Tournaisian-age localities around Northern England and Scotland (Traquair, 1881, 1890; Moy-Thomas, 1937; Gardiner, 1985). The emended diagnosis and description of Styracopterus are thus based only on the remaining catalogued specimens of S. fulcratus, all from from the Visean of Scotland. Among all the ray-finned fishes known from the Visean of Scotland, only Styracopterus and Rhadinichthys laevis Traquair, 1890 are said to reside at Tarras Waterfoot (Moy-Thomas, 1937), a locality not known to contain any other vertebrate or invertebrate remains (Lumsden et al., 1967). The type material of Tarrasius, the namesake fish and the only other taxon ever attributed to those deposits, was actually taken from misidentified Glencartholm sediments (Moy-Thomas, 1933, 1934). Lumsden et al. (1967: 116) suggested that the same was true for the remaining taxa; they did not locate any evidence of a shared fauna or previous fossiliferous locality at Tarras Waterfoot. This assertion was subsequently supported by Dineley & Metcalfe (1999) in a survey of vertebrate material. This distinction might be important: recent work has suggested Tarras Waterfoot sediments may be Tournaisian in age (S. P. Wood, pers. comm.). It is notable that the type specimen of Styracopterus does not differ from Glencartholm material in either matrix or preservational mode, whereas fishes from proximate Tournaisian localities (e. g. Fouldenia), which have different faunal compositions from Glencartholm, are distinct in taphonomy (L. C. S. pers. observ.; Appendix S 1).	en	Sallan, Lauren Cole, Coates, Michael I. (2013): Styracopterid (Actinopterygii) ontogeny and the multiple origins of post-Hangenberg deep-bodied fishes. Zoological Journal of the Linnean Society 169 (1): 156-199, DOI: 10.1111/zoj.12054, URL: http://dx.doi.org/10.1111/zoj.12054
824287C5802BFF8A8A9BFBE7B520F9B0.taxon	description	DESCRIPTION Skull The general structure of the skull in Styracopterus is largely as depicted by Moy-Thomas (1937) and Gardiner (1985). However, there are inaccuracies in those previous reconstructions, caused in part by the combination of differently sized individuals and the inclusion of Fouldenia among the source material. The snout of Styracopterus is capped by a subrectangular rostral with a rounded ventral margin above the level of the infraorbitals, contrary to the reconstruction by Gardiner (1985). The division between the rostral and the premaxilla is indistinguishable in the largest individuals, such as GSE 2136 (Fig. 1 F), where it is obscured by a field of thick ganoine. This is punctured by large round openings that probably mark the sensory canal, as also found in Amphicentrum crassum (Traquair, 1890) (Bradley Dyne, 1939; Coates, 1988), Cheirodopsis (NMS 1885.54.34; L. C. S. pers. observ.), Eurynotus (NMS 1876.28.2, NMS 1957.1.5686; L. C. S. pers. observ.), and Paramesolepis (NMS 1891.53.25; L. C. S. pers. observ.; Appendix S 1). The dorsal limit of the rostral in NMS 1891.53.50 – 51 and GSE 5663 (Fig. 10 D, G) is marked by a patch of U-shaped ornament raised well above the bone and contacting both frontals. The ventral portion of the nasal in Styracopterus expands to a blunt margin in contact with the lachrymal and premaxilla. The dorsal half of the nasal curves almost horizontally to contact the frontal and dermosphenotic. Contrary to the reconstruction of Gardiner (1985), there are no obvious lateral indentations for the nares. Ornamentation varies with size: there is little apparent ganoine in GSE 8731 (Fig. 1 A), whereas a vertical stripe is found in NMS 1891.53.49 (Fig. 1 B). This is joined posteriorly by additional patches of smooth enameloid in GSE 2136 (Fig. 1 F). Similar ornamentation is found on the nasals in Eurynotus (NMS 1876.28.2; L. C. S. pers. observ.) and Benedenius (L. C. S. pers. observ.; Appendix S 1). The skull roof in Styracopterus is similar in composition to previous reconstructions by Moy-Thomas (1937) and Gardiner (1985), but the shapes of the bones differ. The frontals are longer than the parietals, extending from the level of the preoperculum to the midpoint of the lachrymal in the 8 - cm fish GSE 8731 (Figs 1 A, 4 A), and to the level of its anterior margin in larger specimens such as GSE 2136 (Figs 1 G, 4 C). The frontals narrow anteriorly to form a V-shaped contact with the snout series (Fig. 1). The widest portion of the frontal is marked by a rounded point in front of the dermosphenotic in GSE 5663 (Figs 1 G, 4). A posterolateral process that grows larger with size forms a convex (GSE 8731; Fig. 1 G) or V-shaped (NMS 1891.53.49, NMS 1891.53.50 – 51, GSE 5663, GSE 2136; Fig. 1) contact with the parietals. This is contrary to the simple linear suture illustrated by Moy-Thomas (1937) and the convex suture reconstructed by Gardiner (1985), but is similar to Benedenius (Traquair, 1878; Fraipont, 1890; L. C. S. pers. observ.; Appendix S 1). As originally described by Moy-Thomas (1937), the ornamentation of the frontal in Styracopterus varies by size. The frontal in the small fish GSE 8731 (Fig. 1 A) is covered by intercalating ganoine ridges, which largely mirror the lateral margins. Similar ornament is found in the midsized NMS 1891.53.50 (Fig. 1 D), but the striations are broken and joined by small dots medial to the impression of the supraorbital canal. In the equivalently sized NMS 1891.53.49 (Fig. 10 B), more posterior ornament is covered by a large stripe of smooth ganoine. In the largest specimen of Styracopterus, GSE 5663 (Fig. 1 G), this is joined by two bands running along the lateral margins, which are similar to the frontal ornamentation in Benedenius (Fraipont, 1890; L. C. S. pers. observ.; Appendix S 1). Yet, in the equivalently sized individual GSE 2136 (Fig. 4 F), finer ornament is exposed in the same areas (Fig. 1 F). Moy-Thomas (1937) suggested that the large ganoine fields grew directly over the older, smaller ornament, and that appears to be the best explanation for the differences observed within size classes. Similar overgrowth has been observed on the dermal bones of some specimens of Eurynotus, where small striations emerge from under blotched enameloid cover (NMS 1876.28.2; L. C. S. pers. observ.; Appendix S 1) Likewise, Dietze (1999) reported a similar phenomenon in Paramblypterus, where smooth ganoine increased in extent with body size to obscure or replace previous structures. The parietals in Styracopterus are rhomboidal or even right triangular in appearance, not rectangular as reconstructed previously (Moy-Thomas, 1937; Gardiner, 1985). The lateral margin is rounded in small and midrange specimens, and is sigmoidal in GSE 5663 (Fig. 1), extending past the lateral limit of the frontal. The posterior margin contacts the extrascapular at a suture line that appears straight in GSE 8731 (Fig. 1), and slightly inclined towards the midline in the larger GSE 5663 and GSE 2136 (Fig. 1 F, G). The fine linear ornament found in GSE 8731 (Fig. 1 A), NMS 1891.53.50 (Fig. 1 D), and GSE 2136 (Fig. 1 F) radiates posterolaterally, disrupted at the midpoint by a curved vertical ridge described by Gardiner (1985). An elongated band of smooth ganoine covers this ornament in midsize specimen NMS 1891.53.49 (Fig. 1 B). In the 16 - cm GSE 5663 (Fig. 1 G), this is displaced from the midline by smaller dotted ornamentation, and is joined laterally by two or three seed-shaped ganoine splotches. NMS 1891.53.50 (Fig. 1 D) shows a deep furrow for the supraorbital canal along the lateral midline, which curves towards the posterior margin. The dermopterotic gives the superficial impression of a thick, shallow arc stretching back from the lateral frontal (Fig. 4), as has been reconstructed for Strepheoschema (Gardiner, 1985) as well as Cheirodopsis and Canobius elegantulus Traquair, 1881 (Moy-Thomas & Bradley Dyne, 1938). The dermopterotic stretches from a tapered anterior limit, sitting at the midpoint of the frontal in GSE 8731 (Fig. 1 A), and positioned behind the posterolateral process in GSE 5663 (Fig. 1 G), to a diagonal posterior contact with the extrascapular. A fine ornament of short lateral ridges, exposed in GSE 8731 (Fig. 1 A) and GSE 2136 (Fig. 1 F), is almost completely covered by a wide ganoine field running along the midline in 11 - cm NMS 1891.53.49 (Fig. 1 B) and 16 - cm GSE 5663 (Fig. 1 G). Styracopterus possesses one pair of extrascapulars that are rectangular in GSE 8721 (Fig. 10 A), but are laterally expanded, with a curved, ‘ back swept’ appearance in NMS 1891.53.49 (Fig. 10 B) and GSE 5663 (Fig. 1 G), matching the morphology in Phanerosteon ovensi (White, 1927; Appendix S 1; Fig. 18 D) and Eurynotus (NMS 1957.1.5686, L. C. S., pers. observ.). Short, striated ornamentation in NMS 1891.53.50 (Fig. 1 D) is covered by distinct midline and lateral ganoine splotches in NMS 1891.53.49 (Fig. 1 B). In GSE 5663 (Fig. 1 G), these fields are fused into a single patch of smooth ornament with four posterior extensions, covering the lateral half of the bone. The general morphology of the post-temporal in Styracopterus, similar to that described by Moy-Thomas (1937) and Gardiner (1985) in Fouldenia, the remaining Foulden fishes, and in many other early actinopterygians (Gardiner & Schaeffer, 1989; L. C. S., pers. observ.; Appendix S 1), is rhomboid in form (Fig. 1 A, D, F). The posterolateral angle is more pointed, and medial margin short, in the small- est specimen (GSE 8731; Fig. 1 A) relative to the largest (GSE 2136, Fig. 1 G). A primary ornament of thin, posterolaterally diagonal ridges, as shown in GSE 8731 and GSE 2136 (Fig. 1 A, F), is obscured by a half-oval patch of smooth ganoine along the midline NMS 1891.52.49 (Fig. 1 B). In GSE 5663 (Fig. 1 G), this field covers the entire anteromedial portion of the bone, and bears multiple posterior branches. Additional smaller bands and patches of enameloid are found on the posterior half of those post-temporals. The orbit in Styracopterus is bounded by the dermosphenotic, nasal, lachrymal, and jugal, but not the premaxilla, as inferred by Gardiner (1985). The dermosphenotic is unfortunately broken in all known specimens, but may be reconstructed from fragments (Fig. 4). In GSE 8731 (Fig. 1 A), the posterior portion is wide with a ventral margin that curves posterodorsally. The thick process abuts the dermopterotic, and ends on the frontal in GSE 8731, NMS 1891.53.50, and GSE 5663 (Fig. 1 A, D, G). Overall, the morphology matches that in Fouldenia, and likewise lacks the posterior process that would give the dermosphenotic a T-shaped form (contra Gardiner & Schaeffer, 1989). Ornamental ridges are diagonal on the posterior portion in GSE 8731 (Fig. 1 A), and are horizontal on the anterior portion in NMS 1891.53.49 (Fig. 1 B). In GSE 5663, this latter ornament is covered by a drop-shaped splotch of smooth ganoine, just as in Eurynotus crenatus Agassiz, 1833 – 1844 and Benedenius (NMS 1876.28.2, NMS 1957.28.2; Liège Benedenius, L. C. S. pers. observ.; Fraipont, 1890). The jugal is not well preserved in any specimen of Styracopterus, but unornamented sections appear in GSE 8731, NMS 1891.53.50, and GSE 2136 (Fig. 1 A, D, F), where it abuts the preoperculum and extends to the ventral midline of the orbit. The lachrymal is not much better preserved, limited to anterior sections ending near the premaxillae in GSE 8731, NMS 1891.53.49, and GSE 2136 (Fig. 1 A, B, F). These appear rectangular and tall, with some evidence for an ornament of circular ganoine fields in NMS 1891.53.49 (Fig. 1 B). There is no sign of an infraorbital canal. Jaws and dentition The only endoskeletal element known in Styracopterus is the parasphenoid. The dorsal aspect visible in NMS 1891.53.49 (Fig. 1 B) is anteriorly narrow with thin lateral ridges that may mark the parabasal canals, and thus matches the morphology in Fouldenia. The parasphenoid is interrupted near its midline, obscuring the likely position of the bucco-hypophysial canal. However, another posteriorly expanded portion reveals a central ridge and paired triangular indentations, as in the parasphenoids of other early actinopterygians (e. g. Mimipiscis, Choo, 2011; Moythomasia, Gardiner, 1984; Platysomus superbus Traquair, 1881, L. C. S., pers. observ.; Appendix S 1). This is again disrupted by an impression of the hyomandibula obscuring the posterior extent of the bone. The parasphenoid is visible in lateral view in the lower part of orbit in GSE 8731 (Fig. 1 A), where it is inclined anteroventrally and appears quite robust, thickening towards the snout. The maxilla in Styracopterus is largely as described by Moy-Thomas (1937) and Gardiner (1985). The triangular posterior expansion exhibits a rounded peak near the vertical posterior margin of the bone in GSE 2136 (Fig. 1 F), where both maxillae are exposed as mirror images. The dorsal margin slopes into a thick, pointed anterior ramus gradually in GSE 8731 and GM 1905.82 md (Fig. 1 A, B). The transition is steeper and more curved in GSE 2136 (Fig. 1 F), reflecting the deeper posterior expansion in larger individuals (Fig. 4). The jaw margin is sigmoidal in GSE 8731, NMS 1891.53.50 - 1, and GSE 2136 (Fig. 1 A, D, E, F), and overlaps the mandible throughout its length. The margin of the maxilla curves upwards diagonally posterior to the dentary. The general form of the maxilla in Styracopterus is not far from the taller maxillae of Amphicentrum and Cheirodopsis (Moy-Thomas & Bradley Dyne, 1938; Bradley Dyne, 1939; Coates, 1988; L. C. S., pers. observ.; Appendix S 1). The ventral edge of the maxilla in Styracopterus is lined by a wide band of smooth ganoine that covers the entire lateral surface of the anterior ramus (Fig. 1). A second band begins at the level of the anterior edge of the orbit, separated from the first by a deep furrow, and splits into a V-shape posteriorly. The ventral arm runs laterally, whereas the dorsal band moves upwards along the dorsal edge of the maxilla, with both ending at the level of the back of the orbit in smaller specimens: GSE 8731, GM 1902.85 md, and NMS 1891.53.50 - 1 (Fig. 1 A, C, D, E). In the ~ 16 - cm specimens GSE 5663 and GSE 2136 (Fig. 1 F, G), these two bands continue horizontally past the midline of the posterior expansion, with the more ventral member meeting the posterior margin. Smaller blotches of enameloid are found around this ornament (Figs 1, 4). As in the skull roof, the portions of smooth ganoine farther away from the jaw margin, or only present in larger individuals, cover a finer ornamentation, exposed in GM 1902.85 md, NMS 1980.53.49, and GSE 2136 (Fig. 1 B, C, F). This consists of fine, long diagonal ridges radiating posterodorsally onto the posterior expansion of the maxilla from the anterior ramus. Fields of thick ganoine are similarly present on the ventral and anterior maxillae of the eurynotiforms Amphicentrum, Cheirodopsis, Paramesolepis, Wardichthys, Eurynotus, and Benedenius, and in all genera except the last, fine ornament is visible on the posterior expansion (Fraipont, 1890; Coates, 1988; L. C. S., pers. observ.; Appendix S 1). The dentary of Styracopterus extends nearly the entire length of the lower jaw and appears gracile in comparison with the maxilla. The anteriormost portion forms a narrow ‘ beak’ in GSE 8731 and GSE 5663 (Fig. 1 A, F), as the symphysis curves to form an acute point with the edentulous jaw margin. As in Fouldenia and Benedenius (Van Beneden, 1871; Fraipont, 1890; L. C. S., pers. observ.; Appendix S 1), the dentary in Styracopterus is covered laterally by two thick, ganoine bands that are only partially distinct (Fig. 1). The lateral midline is punctuated by a line of large, regularly spaced circular openings for the mandibular canal in GSE 2136 (Fig. 1 F), which resemble the canal pits in the snout ornament. Such openings are also found in the smooth ganoine covering the mandibles of Eurynotus (NMS 1957.1.5686; L. C. S., pers. observ.) and Amphicentrum (Coates, 1988; Appendix S 1). As reconstructed by Gardiner (1985), the angular in Styracopterus is a narrow, half-crescent in GSE 8731, NMS 1891.53.51, and GSE 2136 (Fig. 1 A, D, F), and is similar in general morphology to those in Cheirodopsis and Paramesolepis (Moy-Thomas & Bradley Dyne, 1938; Appendix S 1). Moy-Thomas (1937) and Gardiner (1985) noted, but did not illustrate, ‘ eight cylindrical blunt teeth’ found on the maxilla of Styracopterus specimen GM 1902.85 md (Fig. 1 C). In this individual, the anterior process of the maxilla bears a homogeneous set of large, triangular teeth with acrodin caps, tapered crowns, and robust bases. The morphology and preservation are superficially similar to a robust set of teeth along the margin of an isolated jaw of Mesolepis wardi Young, 1866 (NHM P 8044; L. C. S., pers. observ.), and a maxillary tooth visible on the anterior portion of the maxilla in a specimen of Paramesolepis tuberculata (Traquair, 1890) (NMS 1891.53.25; L. C. S., pers. observ.). Likewise, the Eurynotus crenatus specimen NMS 1859.33. F 515 (L. C. S., pers. observ.) shows the impression of such an acrodin-caped fang well forward of and distinct from the denticulated tooth plates, and specimen NHM P 11679 has a full row of pointed teeth on the mesial surface of the maxilla above the jaw margin (Traquair, 1879; L. C. S., pers. observ.). Evidence of marginal dentition remains confined to GM 1902.85 md (Fig. 10 C); all other individuals exhibit a seemingly edentulous gape covered in ganoine ornament. The marginal dentition of other Styracopterus specimens might be obscured by a ‘ beak’ of dermal bone and / or ganoine plate, as the maxilla significantly overlaps the mandible in articu- lated jaws. Unfortunately, the mesial surface of the maxilla is not observed, preventing confirmation. However, Amphicentrum, another superficially edentulous fish, has a field of apparent tooth cusps on the mesial maxilla, well dorsal to the sharpened edge of the gape (Bradley Dyne, 1939; Coates, 1988; NMS 1894.73.472; L. C. S., pers. observ.; Appendix S 1). Likewise, the maxillary teeth in Eurynotus sit in an internal position, hidden from lateral view, and are thus not visible in most specimens (Traquair, 1879; NMS 1859.33. F 515; L. C. S., pers. observ.; Appendix S 1). Within the Glencartholm fauna, Cheirodopsis has a set of six or more incisor-shaped teeth rooted on the mesial side of the maxilla, covered laterally by ganoine-ornamented bones (NMS 1957.1.5781; L. C. S., pers. observ.). Farther afield temporally and geographically, a similar, but reversed, arrangement is found Aeduella, where a ‘ flange’ of the maxilla covers the lingual aspect of tooth bases (Gottfried, 1987). In NMS 1891.53.50 – 51 (Fig. 1 D, E), an individual in which the dermal cheek bones are missing, two near-parallel rows of denticles lacking acrodin caps are situated medial to, and separate from, the remnants of the dentary, but show some alignment with the lower jaw. The crowns of these anteriorly ovoid and posteriorly rectangular denticles are pointed outwards from the matrix. The rows are separated by an area in line with the width of the frontals in the same individual and / or the parasphenoid in the similarly sized specimen NMS 1891.53.49 (Fig. 1 B), which also possesses outwardly oriented denticles alongside the anterior limit of the palate. The denticles are probably associated with lower tooth plates, as in Fouldenia (see below), Mesolepis wardi (NHM P 8042; L. C. S., pers. observ.), and Eurynotus crenatus (NMS 1859.33. F 515; L. C. S., pers. observ.), which have highly similar denticle morphologies. These plates would probably have been constructed from the fused coronoids or other mesial mandibular elements, as described for similarly positioned elements in Amphicentrum granulosum Young, 1866, Cheirodopsis, and Eurynotus (Bradley Dyne, 1939; Traquair, 1879; Coates, 1988; L. C. S., pers. observ.; Appendix S 1). Specimen NMS 1891.53.50 – 51 also shows a second pair of denticle rows situated around the midline of the disarticulated skull (Fig. 1 D, E), again with crowns pointed outwards. These denticles are conical with blunted apices, the largest featuring a narrow, ‘ lophodont’ edge perpendicular to the row, and showing signs of wear-related loss at their crowns. The denticles are heterogenerous in both spacing and size: many of the more posterior members are an order of magnitude larger than the mandibular denticles, whereas more anterior elements are smaller and more broadly spaced. This is similar to the arrangement of the primary, ventrally pointed row of denticles on the upper toothplates of Eurynotus and Mesolepis (Traquair, 1879; Watson, 1928; NMS 1874.3 A; L. C. S., pers. observ.; Appendix S 1). As with the mandibular set, the space between the upper rows of denticles in NMS 1891.53.50 – 51 matches the width of the parasphenoid at the same points in NMS 1891.53.49, narrowing anteriorly (Fig. 1 B, D, E). In NHM P 1663, where a badly preserved skull is observed in nearly ventral view, small, closely packed denticle crowns distinguishable from the maxillary teeth are pushed through a gap just ventral to the mandible and away from the maxilla. The orientation of the denticles in NMS 1891.53.50 – 51 (Fig. 1 D, E) and NHM P 1663 suggests the existence of paired palatal tooth plates with ventrally pointed denticles, perhaps derived from the ectopterygoids, as in Amphicentrum and Cheirodopsis (Traquair, 1879; Moy-Thomas & Bradley Dyne, 1938; Bradley Dyne, 1939; Coates, 1988; L. C. S., pers. observ.; Appendix S 1). Suspensorium As previously described, the suspensorium in Styracopterus is nearly vertical (Moy-Thomas, 1937; Gardiner, 1985). This is supported by the impression of a superficially narrow and cylindrical hyomandibula in NMS 1891.53.50 (Fig. 1 D), in which a knoblike opercular process marks the transition from the erect ventral portion to a slightly inclined dorsal half. The true and relative sizes of these parts may be obscured by overprinting of the dermal bones. The head of the hyomandibula is expanded and robust in NMS 1891.53.50, GSE 8731, and possibly GSE 5663 (Fig. 1 A, C, G). The head is covered by a triangular dermohyal with fine, linear ornament and a dropshaped ganoine patch, as noted in GSE 2136 and GSE 5663 (Fig. 1 A, G). The hyomandibula is bounded anteriorly by a very erect preopercular, fully preserved in Styracopterus specimen GSE 2136 (Fig. 1 F; Gardiner, 1985), which is positioned so that the vertical anterior margin aligns with the rear of the gape. The posterior margin is bounded by a cylindrical ridge and tracks the angle of the hyomandibular, bending diagonally at the level of the horizontal pitline in GSE 2136 to form the narrow, rounded apex (Fig. 1 F). The preopercular thus resembles those in Amphicentrum (Coates, 1988), Eurynotus (Gardiner & Schaeffer, 1989), Cheirodopsis, and Paramesolepis (Moy-Thomas & Bradley Dyne, 1938; L. C. S., pers. observ.; Appendix S 1). The ornament above the premaxilla consists of fine striations radiating from the midline, whereas a ventral process connecting with the quadratojugal is covered in smooth ganoine (Fig. 1 F, G). Opercular series The operculum is small and rectangular in the specimen of Styracopterus with the best-preserved example: the large fish GSE 5663 (Fig. 1 G). In line with Moy-Thomas’ (1937) reconstruction, The suboperculum is taller and is almost identical to that in Benedenius (Traquair, 1878; Fraipont, 1890; L. C. S., pers. observ.; Appendix S 1; Fig. 15 C). It exhibits a pointed anteroventral process angled towards the jaw joint by a diagonal ventral margin, as in Benedenius and Fouldenia (L. C. S., pers. observ.; Appendix S 1; Fig. 15). This process might be considered diagnostic for Styracopteridae, were similar structures not present in Tarrasius, Strepheoschema, Holurus, Phanerosteon, Paramesolepis, Amphicentrum, Eurynotus, and Cheirodopsis (Moy-Thomas & Bradley Dyne, 1938; Gardiner, 1985; Coates, 1988; Gardiner & Schaeffer, 1989; Sallan, 2012; L. C. S., pers. observ.; Appendix S 1). There are differences in the relative sizes and orientation of opercular series bones between Styracopterus size classes. In 8 - cm GSE 8731 (Fig. 1 A), the operculum is inclined forwards at an almost 45 ° angle, and is nearly equal in length to a curved suboperculum (Fig. 4 A). In 11 - cm specimens NMS 1891.53.49 and NMS 1891.53.50 – 51 (Fig. 1 B, D), the operculum is still tilted slightly anteriorly and ends just above the curved preopercular, giving way to a taller suboperculum (Fig. 4 B). In GSE 2136 (Fig. 1 F), a posteroventrally diagonal line bisects the operculum ornament into an anterior field of curved lateral ridges and a posterior field of concentric lines. This is obscured in larger individuals such as NMS 1891.53.49 (Fig. 1 B), in which a broken plate of ganoine is found near the anteroventral corner. The ornament of the suboperculum is also double layered in larger specimens of Styracopterus. Thick, wavy lines radiate posteriorly from a primary vertical stripe of ganoine in GSE 2136 (Fig. 1 F). In contrast, the anteroventral process is covered by diagonal ridges in GSE 5663 (Fig. 1 G); although this is obscured by smooth ganoine distally. In that same specimen, elongate enameloid bands are found on the ventral half of the suboperculum. Similar ornament is found on an articulated suboperculum from the late Tournaisian deposits of Symond’s Yat, Herefordshire, England, previously attributed to Styracopterus sp. (NHM P 62956; L. C. S., pers. observ.; Appendix S 1, see below), as well as the more extensive smooth ganoine of the Liege specimen of Benedenius (Fraipont, 1890; L. C. S., pers. observ.; Appendix S 1). Gulars and branchiostegals The branchiostegal rays are not completely preserved in Styracopterus, although individual rays are found in several specimens. The primary ray is the tallest and most distally expanded in GSE 5663 (Fig. 1 G), and bears an ornament of two intercalated and wavy bands (Figs 1 G, 4 C). The second ray is thinner but likewise ornamented, but further members of series are covered with one or two longitudinal enameloid bands and / or fine linear ornament (Figs 1 G, 4 C). Whereas rectangular branchiostegals directly under the opercular bones are elongate, those originating ventral to jaws in GSE 8731 and NMS 1891.53.49 (Fig. 1 A, B) are shorter and more pointed, but remain nearly horizontal in orientation. This is similar to the general orientation and form of the series in Benedenius (Fraipont, 1890) and most other eurynotiforms (e. g. Amphicentrum, Cheirodopsis, Eurynotus; Traquair, 1879; Moy-Thomas & Bradley Dyne, 1938; Coates, 1988; L. C. S., pers. observ.; Appendix S 1), in which the ventralmost branchiostegals are relatively short and barely visible in lateral view (Fig. 15). The only evidence of the gular series consists of a badly preserved, displaced lateral gular originating just posterior to the front of the dentary in NMS 1891.53.49 (Fig. 1 B) and similar in form to the branchiostegals. Unlike the branchiostegals, the gular is completely covered in ganoine (Fig. 1 B). The arrangement of the preserved parts leaves space for a short median gular, as in Fouldenia, but it is not clear whether more anterior skeletal material represents this bone. Gular material in other specimens might be hidden by the mandible, as appears to have been the case in Benedenius, Amphicentrum, Eurynotus, Cheirodopsis, Paramesolepis and other early fishes (Traquair, 1879; Fraipont, 1890; Moy-Thomas & Bradley Dyne, 1938; Coates, 1988; L. C. S., pers. observ.; Appendix S 1; Figs 15 – 19). Shoulder series The dermal shoulder series in Styracopterus is relatively well preserved and matches the composition described by Moy-Thomas (1937). Unfortunately, the same cannot be said for the endoskeletal girdle, which is not visible in any specimen. The leaf-shaped supracleithrum extends to the midpoint of the suboperculum (Figs 1, 4). The ornament consists of prominent, densely packed, intercalating ganoine ridges running along the vertical axis and fusing towards the midline. The supracleithrum changes from a thin gracile bone with a definite ventral point in the 8 - cm specimen GSE 8731 (Fig. 1 A) to a wide, rounded form in the 16 - cm individuals GSE 5663 and GSE 2136 (Fig. 1 F, G). The rectangular postcleithrum in Styracopterus is wide and elongate, but would have been obscured in life by the supracleithrum, except for a rounded posteroventral corner abuting the cleithrum, as shown in GSE 8731 (Fig. 1 A). Exposed postcleithra in other specimens resemble the same bone in Amphicentrum (Coates, 1988). The ornament preserved in GSE 5663 (Fig. 1 G) consists of thick diagonal striations. The cleithrum in Styracopterus is very tall and erect, with a wide crescent-shaped dorsal process and a tall ventral body with a rounded posterior extension (Figs 1, 4). Thus, it resembles the cleithra of other eurynotiforms, particularly Fouldenia and Eurynotus (Traquair, 1879; Gardiner & Schaeffer, 1989; L. C. S., pers. observ.; Appendix S 1; Fig. 15). The half-ovoid dorsal process of the cleithrum runs to the midpoint of the suboperculum in GSE 8731, NMS 1891.53.50, and GSE 5663 (Fig. 1 A, D, G). The ornament in Styracopterus specimen GSE 8731 (Fig. 1 A) is similar to Fouldenia, and other Foulden taxa (L. C. S., pers. observ.; Appendix S 1), in that it consists of robust, nearly vertical lines running from apex to base (Fig. 13 A). This ornament is covered by wider bands of smooth ganoine in the larger specimens NMS 1891.50.49 and GSE 2136 (Fig. 1 B, F). The ventral part of the cleithrum is tall in GSE 2136, and features an ornament of short horizontal ridges covered by smooth enameloid. Like Fouldenia, there is a short posterior extension near the ventral surface of the cleithrum. The cleithrum contacts the clavicle at a concave anterior margin situated beneath the opercular series and jaw joint in NMS 1891.50.49 (Fig. 1 B). The clavicle in Styracopterus runs along nearly the entire ventral length of the skull, as exposed in GSE 8731, NMS 1891.50.49, GSE 2136, and GSE 5663 (Fig. 1 A, B, F, G), curving anteriorly to a rounded point. The clavicle of Styracopterus is shallow relative to that of Fouldenia, and is completely covered by the mandible in life (Figs 1, 4). The bone is covered with short, wavy bands in NMS 1891.53.49 and GSE 5663 (Fig. 1 B, G), an ornament obscured by smooth ganoine patches in the latter. Paired fins The pectoral fins in Styracopterus originate ventrolaterally, although the endoskeletal attachment is not visible in any specimen. However, GSE 8731 and GSE 5663 – 4 (Fig. 2 A, E, F) show a gap in squamation between the cleithrum and the angled bases of the lepidotrichia, which suggests a naked lobe over the missing radials. The fins in GSE 8731 (Fig. 2 A) are elongate and curved, with pointed distal margins and short bases. This results in a scythe-shaped fin similar to those in Eurynotus, Benedenius, and Mesolepis (Agassiz, 1833 – 1844; Traquair, 1879; Boulenger, 1899; Traquair, 1907; L. C. S., pers. observ.; Appendix S 1; Fig. 15). In this individual and others (GSE 5663 – 4, NMS 1891.53 – 50; Fig. 2 C, E, F), lepidotrichia are thin and tightly packed with enlarged ovoid bases, similar to the median fin rays in Fouldenia. Segments are rectangular, with a ridge along the anterior edge. The rays become thinner distally but there is no evidence for bifurcation. Rays supporting the anterior margin in the 16 - cm specimen GSE 5663 – 4 (Fig. 2 E, F) are more robust than, and may be twice as wide as, the other lepidotrichia, with an abrupt transition. However, the absolute size of the fin is invariant between specimens despite a doubling of body length, rendering it relatively larger in smaller specimens. Traquair (1881) noted impressions of robust pectoral fringing fulcra in the holotype of Styracopterus (GSE 5672 – 3; Fig. 2 D), and these served as a basis for the species and eventually genus names (Traquair, 1890). Elongate, blade-like fulcra strongly resemble their likewise paired counterparts in Eurynotus (NHM P 11679, NHM P 11676; L. C. S., pers. observ.; Appendix S 1), and those of Benedenius in lateral view (Traquair, 1879; Fraipont, 1890; Appendix S 1). Each fulcral scale possesses a tapered distal margin and is covered by thick ganoine. More distal pairs are progressively shorter and thinner. In the smallest specimen, GSE 8731 (Fig. 2 A), six pairs of fulcral scales sit along the primary lepidotrich, each overlapping a third of the length of their neighbour. The number of fulcra is unchanged in larger specimens NMS 1891.53.50 – 51 (Fig. 2 B, C) and GSE 5663 – 4 (Fig. 2 E, F), yet more distal scales appear lozengeshaped rather than elliptical. These contact each other at nearly straight margins oriented at a 45 ° angle relative to the fin axis. The pelvic fins of Styracopterus sit very low on the body, separated by a distance of just two or three median ventral scales in NHM P 1663 (Fig. 2 G). The fins appear small and triangular, but may be truncated by the better-preserved anal fin. The lepidotrichia in NHM P 1663 and GSE 8731 (Fig. 2 G, H) are thin and densely packed, divided into elongate segments with no evidence of bifurcation, thus resembling the pectoral rays of Fouldenia. The similarly sized individual GSE 8731 (Fig. 2 H) possesses fringing fulcra that are slimmer versions of their pectoral counterparts. These are similar to the proximal fringing fulcra on the pelvic fins in a very small specimen of Eurynotus (NMS 1874.3 A; L. C. S., pers. observ.; Appendix S 1). A furrow on the anterior midline of each fulcral scale originates from a wider groove holding the apex of its more proximal neighbour. Three semi-articulated pelvic fulcra are observed in lateral view in the larger specimen GSE 5663 – 4 (Fig. 11 I), and appear relatively thicker and wider. A large, ovoid basal fulcral scale overlaps the pelvic fin in both NHM P 1663 and GSE 5663 – 4 (Fig. 2 G, I). This is ornamented with three thick longitudinal bands of ganoine that fuse near the apex of each scale. Unfortunately, the endoskeletal components of the pelvic complex are not visible in any specimen. Median fins An exact reconstruction of the dorsal fin in Styracopterus was not possible because of incomplete preservation. However, GSE 8731 (Fig. 3 A) suggests a long yet sloped anterior margin, whereas GSE 5663 – 4 (Fig. 3 C, D) shows the posterior portion is quite short and rounded. The fin base sits along the diagonally oriented dorsal margin of the body, originating near the point of maximum depth in larger specimens GSE 5672 – 3 and GSE 5663 – 4 (Fig. 3 B, C, D). In GSE 8731, GSE 5672 – 3, and GSE 5663 – 4 (Fig. 3 A, B, C, D), the primary lepidotrichia are unjointed, have ovoid bases, and are fused to fringing fulcra like those of the paired fins, just as the leading fin rays of the dorsal fins in Fouldenia, Amphicentrum, Cheirodopsis, Eurynotus (NMS 1876.28.2 and NHM P 11676), Paramesolepis, and Wardichthys, among other eurynotiforms (L. C. S., pers. observ.; Appendix S 1). These have been refered to elsewhere as ‘ horns’ (Weems & Windolph, 1986). Other lepidotrichia supporting the anterior margin of the dorsal fin in GSE 5672 and GSE 5663 – 4 (Fig. 3 B, C, D) are proximally double the width of those in the posterior half of the fin, which is another commonality with the Eurynotiformes mentioned above (L. C. S., pers. observ.; Appendix S 1). Although rays in the anterior portion of the dorsal fin taper to a point, bifurcation is observed in more posterior lepidotrichia, with extent increasing towards the posterior. This biased distribution of dichotomization is also found in Amphicentrum, Eurynotus, and Aesopichthys (Coates, 1988; Poplin & Lund, 2000; L. C. S., pers. observ.; Appendix S 1). It seems to allow more posterior flexibility, as indicated by the non-uniform orientations in which these lepidotrichia are preserved in Styracopterus. The angle of fin-ray origination decreases gradually along the dorsal fin. This is aligned with a loss in height following a peak in the anterior half of the fin. Other styracopterid and eurynotiform fishes also have such posteriorized peaks relative to Platysomus, Aesopichthys, and other deep-bodied ray-finned fishes (L. C. S., pers. observ.; Appendix S 1). Lozenge-shaped, paired fringing fulcra on the dorsal fins of Styracopterus resemble the distalmost fulcra on the pectoral fins (Fig. 3 A, B, C). Eurynotus also features paired scales on its dorsal fin (NMS 1876.28.2; L. C. S., pers. observ.; Appendix S 1), yet fringing fulcra are usually singular on the median fins of other early actinopterygians (e. g. Platysomus and Aesopichthys; L. C. S., pers. observ.; Appendix S 1). The anal fin is exhibited in lateroventral view in NHM P 1663, and the larger specimen GSE 5663 – 4 (Fig. 3 E, F, G) displays a nearly complete fin in part and counterpart. The anal fin of Styracopterus is an acute triangle with slightly curved margins rather than the sickle shape of Fouldenia (Figs 4, 13). The anal fin in Styracopterus has a short base originating in the posterior third of the trunk. It bears lepidotrichia resembling those of the dorsal fin in terms of morphology, as well as changes in dichotomization and height along the fin. Likewise, there is an increase in the relative thickness of the primary anal lepidotrichia with body size in Styracopterus, such that fewer rays appear to make up the anterior margin in GSE 5663 than NHM P 1663 (Fig. 3 E, F). In GSE 5663 – 4 (Fig. 3 F, G), these lepidotrichia appear to bifurcate into curved terminal segments, conforming to the fringing fulcra. It is not clear whether this is a preservational artifact, a trait specific to the anal fin, or a general characteristic of Styracopterus obscured in other fins. In this same individual, proximal fulcral scales are like their pectoral fin equivalents, but more distal fulcra are squat and trowel-shaped, with much greater overlap between successive pairs. These approximate the fringing fulcra morphology in Cheirodopsis and Eurynotus (NMS 1874.3 A, P 42077, NMS 1876.28.2, NMS 1893. 20; Moy-Thomas & Bradley Dyne, 1938; L. C. S., pers. observ.; Appendix S 1). In Eurynotus, the fulcra form a thick and almost solid anterior margin for the anal fin, just as in Styracopterus (L. C. S., pers. observ.; Appendix S 1). In NHM P 1663 and GSE 5663 – 4 (Fig. 3 E, F, G), erect basal fulcra precede the anal fin, with the last two doubling the height of their anterior neighbours to overlap the fringing fulcra. An expanded base supports an elongated distal process, superficially divided into two rami. The proximal portions also resemble the successively taller, spine-like anal basals found in Amphicentrum, Cheirodopsis, and Eurynotus (L. C. S., pers. observ.; Appendix S 1). Tail and caudal fin The posteriormost portion of Styracopterus is only preserved in GSE 5663 – 4 (Figs 3 H, I, 12 J), which possesses a nearly complete tail and caudal fin. Styracopterus has an epichordal fin, which appears to be diamond-shaped and lacks fulcra (Fig. 3 H, I, B). It originates dorsally and ventrally after a two- or threescale-wide gap following the posterior margin of the caudal fin and the apex of the last axial fulcral scale. The fine, well-separated lepidotrichia emerge diagonal to the body wall, have short segments, and taper distally without bifurcation. Although epichordal fins and lobes are ancestral for osteichthyans, and possibly gnathostomes, the loss of this fin was once thought to define the actinopteran crown (see discussion in Patterson 1982 and Gardiner & Schaeffer, 1989). This was because such a fin was associated primarily with the Devonian stem-taxon Cheirolepis among Palaeozoic fishes, and with Polypterus among living forms (Pearson, 1982; Long, 1988; Arratia & Cloutier, 1996). However, Watson (1925) found the same structure in the Permian taxon Palaeoniscum, whereas Patterson (1982) noted a wider but incomplete distribution, involving derived taxa such as Bourbonnella (Gardiner & Schaeffer, 1989). In fact, Fouldenia (Figs 11, 12) and other Eurynotiformes such as Paramesolepis (NHM P 20425 – 6; L. C. S., pers. observ.) and Cheirodopsis (NHM P 20222; L. C. S., pers. observ.) also bear distinct epichordal fins, as do most examined Palaeozoic actinopterygians with elongate axial lobes and completely preserved tails (L. C. S., pers. observ.; Appendix S 1). This suggests the presence of an epichordal fin could be the base state for all Palaeozoic actinopterygians, and will require further investigation. Whereas the tail of Styracopterus is superficially inequilobate in GSE 5663 – 4 (Fig. 3 H), the caudal fin itself is nearly homocercal, with a shallow median cleft. The ventral lobe is large and rounded. Lepidotrichia are similar in segment morphology to those of the median fins, and start tapering at around threequarters of their length. While the majority of lepidotrichia are missing their tips, those in the ventral lobe tend to end in a pointed segment, whereas more dorsal fin rays bifurcate with no apparent regularity. Bifurcation is also observed in lepidotrichia underlying the fringing fulcra and ventral / anterior margin (Fig. 3 H, J), as in the anal fin. Although the lepidotrichia in the dorsal lobe are finer than those near the anterior margin, the transition is not as abrupt as in the median and paired fins. Caudal basal fulcra form a continuous series between the anal and caudal fins (Fig. 3 G, H, J). The basals resemble the anal set: more anterior basals are squat with rounded apices and linear ornament oriented parallel with the body axis (Fig. 3 G). They transition into tall, erect scales with wide bases and long posterior processes that expand distally, giving them a slightly sigmoid appearance. These abut the primary caudal lepidotrichia. The distal processes consist of two triangular rami joined at the midline around a central groove and furrow. These have a deltoid shape in lateral view. Fringing fulcra are prominent along the ventral margin of the caudal fin (Figs 3 H, J, 4), and resemble the set on the anal fin of the same individual and in Eurynotus (L. C. S., pers. observ.; Appendix S 1). The first caudal lepidotrich in Styracopterus has very thick, almost fulcra-like proximal segments, and appears to blend into this set. Squamation GSE 5663 – 4 (Fig. 4 C), the largest and most complete specimen of Styracopterus, possesses 74 sigmoidal trunk scale rows. These rows curve such that the dorsalmost scales have their posterior margins directed near vertically. The laterally compressed GSE 5663 – 4 (Fig. 4 C) has 25 scales per row over most of the flank, despite posterior decreases in body depth. The smaller, more roundly fusiform GSE 8731 (Fig. 4 A) has just 18 scales per row at maximum depth, indicating that scale counts increase during ontogeny yet scale height is ultimately related to body depth. A prominent ‘ hinge line’ is found on the caudal peduncle of GSE 5663 – 4 (Figs 3 H, 4 C), marking the start of ~ 61 additional caudal scale rows along the peduncle and axial lobe. Scales on the lateral trunk are tall and largely rhomboid, with smooth margins and rounded posteroventral corners. Imprints of the mesial side of these scales in NMS 1891.53.51 (Figs 2 B, 4 A) show tall, robust pointed pegs originating from the middle of the dorsal margin and sitting within a similarly shaped central divot on the next member of the row. Fraipont (1890) and Boulenger (1899) illustrated nearly identical flank scales in Benedenius, and the same general morphology and articulation is found in Amphicentrum, Eurynotus, Cheirodopsis, and other eurynotiforms (Agassiz, 1833 – 1844; Traquair, 1879; Bradley Dyne, 1939; Coates, 1988; L. C. S., pers. observ.; Appendix S 1). Lateral line scales in Styracopterus are marked by a horizontal, cylindrical ridge running along the horizontal midline. These scales otherwise match their neighbours in size and ornamentation. The ornament, shape, and relative heights of flank scales vary between size classes and positions on the trunk. In the ~ 8 - cm, largely fusiform individuals GSE 8731 and NHM P 1663 (Fig. 4 A), the tallest, most rectangular scales are found ventral to the lateral line on the anterior flank. These bear up to six lateral bands of ganoine. The top three of these are dorsoventrally directed and form a leaf-shaped, nested pattern similar to the scale ornament in Fouldenia. The bottom three bands are more horizontal, tapering and fusing posteriorly. Shorter scales near the midpoint of the body have truncated versions of the same ornament, with the reduction in height sucessively eliminating more ventral stripes. Even shorter scales near the dorsal and ventral margins in the anterior half of the body, and all scales on the posterior half, are simply ornamented with four horizontal, rectangular bands that fuse posteriorly (Fig. 4 A). Such scales have a greater anterodorsal slope and a more prominent posterodorsal margin than their counterparts along the anterior flank, giving them a leaf-like form similar to the trunk squamation of smaller specimens of Fouldenia (Fig. 13). This also describes nearly the entire flank squamation in the smallest two Styracopterus specimens, GSE 8731 and NHM P 1663 (Fig. 4 A), which is far more homogeneous than large individuals. In the midsize individuals GSE 5672 – 3, NMS 1891.53.50 – 51, and NMS 1891.53.49 (Fig. 4 B), the nested ornament increases in size to contain up to seven concentric bands, resembling the anterior flank scales of the largest specimens of Fouldenia (Fig. 13 D). Scales near the ventral margins of the anterior half of the body in midsize Styracopterus are ornamented entirely by nested ridges, rather than the simple striations found in the smaller GSE 8731 (Fig. 4 A, B). Scales on the dorsal surface and posterior half of midsize fish are taller than their counterparts in GSE 8731 (Fig. 4 A, B), and bear an additional horizontal ganoine band. A distinct field of ovoid scales is found near the dorsal fin in midsize Styracopterus, such as GSE 5672 – 3 (Fig. 3 B), with posterior margins oriented towards the lepidotrichial bases. These are covered with three or four flat ganoine lines that fuse at the apex, resembling the ornament of the pelvic basal fulcra in miniature. In the largest individuals, GSE 5663 – 4 and GSE 2136 (Fig. 4 C), anterior flank scales are elongate and rectangular, with an ornament of nine or ten diagonal striations over three horizontal bands. The nested pattern is broken; most of the ridges run off the posterior edge or fuse with a marginal line of ganoine. The more dorsal and ventral scales remain rhomboid, adding yet another horizontal line of ganoine to bring the total to six per scale (Fig. 4 C). Scales on or near the caudal peduncle in GSE 5663 – 4 do not differ greatly from the posterior flank scales of smaller specimens, and become shorter and more elongately rhomboid near the caudal fin base (Figs 3 H, J, 4 A, C). There is no evidence of a distinct field of squamation along the anteroventral surface of the trunk in Styracopterus, unlike Fouldenia (see below). Nor is there a trace of ventral ridge scales in the smallest specimen NHM P 1663 (Fig. 4 A). However, two slightly enlarged, deltoid scales are visible on the ventral margin around the trunk midline in the midsize fish NMS 1891.53.49 (Fig. 4 B). These bear an ornament of fine longitudinal bands. In the largest specimen, GSE 5663 – 4 (Figs 2 E, F, 4 C), a series of four squat, trapezoidal scales is preserved in medial view at the ventral margin of the body, just anterior to the pelvic basal fulcra. These ventral ridge scales cover a third of the distance between the shoulder girdle and pelvic fins. However, anterior members of the series could be obscured by the intact pectoral fins. The ridge scales are not much larger than the adjacent trunk squamation, and thus their overall state is similar to that in Benedenius (Traquair, 1878; Fraipont, 1890; Boulenger, 1899; L. C. S., pers. observ.; Appendix S 1). Prominent ridge scales cover the entire dorsal midline from nape to fin in Styracopterus, as originally illustrated for the holotype by Traquair (1881, 1890; Moy-Thomas, 1937; Gardiner, 1985). Scales in the anterior half of the series are smaller, more rounded, and horizontally oriented than the erect ridge scales near the dorsal fin (Figs 3, 4); however, ontogenetic differences are apparent. In the 8 - cm fishes GSE 8731 and NHM P 1663 (Figs 3 A, 4 A), horizontal ridge scales along the anteriormost dorsum have rounded margins but are otherwise indistinguishable from the proximate trunk squamation, in contrast to the more erect, spine-like members in the posterior half of the series. These ridge scales have a rounded proximal portion joined to a curved, pointed apex, and an ornament of thick vertical striations. In the midsize fish NMS 1891.53.50 – 51, NMS 1891.53.49, and GSE 5672 – 3 (Fig. 4 B), the dorsal ridge scales are enlarged and the anteriomost members are distinguishable by their acuminate shape and central grooves. The longitudinal ornament found in smaller fish is replaced by thick horizontal bands in more posterior ridge scales (Fig. 4 B). Although the posterior half of the dorsal ridge series is unknown in the largest specimens (GSE 5663 – 4, GSE 2136; Fig. 4 C), the anteriormost ridge scales have the same morphology as the most posterior scales of the smallest specimens (Fig. 4 C). Pointed ridge scales overlap each other at 45 ° angles and bear a diagonal banded ornament. Caudal squamation is only observed in GSE 5663 – 4, but exhibits considerable variation along the length of the peduncle and axial lobe (Figs 3 H, J, 4 C). Peduncle squamation above the hinge line consists of rhomboid scales with rounded margins and thick ganoine cover; however, scales situated along the lepidotrichial bases are small and seed shaped, with no discernable ornament pattern. Elongate, diamond-shaped scales cover the base of the axial lobe and feature a single furrow in their otherwise solid ornament. These transition to smaller, seed-shaped scales at the horizontal midpoint of the axial lobe, yet the ornament pattern is retained (Fig. 4 C). Smaller versions of these scales are found in the portion bearing the epichordal fin. The basal and fringing fulcra on the peduncle and axial lobe are very similar in morphology to those in Fouldenia and Benedenius (Traquair, 1878; Fraipont, 1890; L. C. S., pers. observ.; Appendix S 1; Figs 3 H, 4 B, C, 12 A, B, 13). The scales in Styracopterus decrease in size and length posteriorly, so that the last few resemble the paired fulcra of the median fins (Fig. 3 H, I). As in Fouldenia and Benedenius (Fraipont, 1890; L. C. S., pers. observ.; Appendix S 1), The distalmost fulcral pair in Styracopterus occurs at the level of the last caudal fin ray base (Fig. 3 H, I).	en	Sallan, Lauren Cole, Coates, Michael I. (2013): Styracopterid (Actinopterygii) ontogeny and the multiple origins of post-Hangenberg deep-bodied fishes. Zoological Journal of the Linnean Society 169 (1): 156-199, DOI: 10.1111/zoj.12054, URL: http://dx.doi.org/10.1111/zoj.12054
824287C58038FF8A8B68F9BCB496FD53.taxon	materials_examined	Type and only species: Fouldenia ischiptera (Traquair, 1881). Diagnosis (emended from Moy-Thomas, 1937): Styracopterid eurynotiform fish with three longitudinal ganoine bands sitting parallel with and alongside jaw margins on maxilla and dentary; maxillary teeth small, blunt, and rounded; mandibular tooth plate denticles with constricted base and blunt crown; dentary deep with blunt anterior margin; maxilla with blunt anterior ramus and rounded triangular posterior expansion; rostral bearing horizontal bands of ganoine; frontal with straight lateral margin; parietal with straight lateral margin; suspensorium 45 ° off vertical; preopercular with concave anterior and convex dorsoposterior margins; opercular half-ovoid and equal in length to subopercular; long axis of branchiostegals long and held away from ventral margin of dentary; paired fin lepidotrichia cylindrical and thin; flank scales ornamented with nested lines of ganoine in adult; distinct anteroventral squamation with juvenile scales in adult; pelvic fin preceeded by two enlarged basal fulcra; anal fin with strongly concave posterior margin. Occurrence: Late Tournaisian of Scotland and England.	en	Sallan, Lauren Cole, Coates, Michael I. (2013): Styracopterid (Actinopterygii) ontogeny and the multiple origins of post-Hangenberg deep-bodied fishes. Zoological Journal of the Linnean Society 169 (1): 156-199, DOI: 10.1111/zoj.12054, URL: http://dx.doi.org/10.1111/zoj.12054
824287C58038FF858952FCD7B5C6FA84.taxon	materials_examined	Holotype: GSE 2187 (M 1122 b, holotype of ‘ Styracopterus ischipterus ’), British Geological Survey, Edinburgh, UK, nearly complete articulated individual in part (EBL: 6 cm). Paratypes: NHM P 13178 (holotype of ‘ Fouldenia ottadinica ’), Natural History Museum, London, UK, nearly complete, flattened articulated individual showing dorsal aspect in part (EBL: 9 cm); NHM P 13179, impression of complete articulated skull in part (EBL: 8 cm); NHM P 13187 (part) and NHM P 13188 (counterpart), nearly complete articulated individual (EBL: 5 cm); NHM P 13180 (part) and NHM P 14560 (counterpart), incomplete articulated anterior half of individual (EBL: 8 cm); NHM P 13182 (part) and NHM P 13183 (counterpart), incomplete articulated anterior half of individual (EBL: 8.5 cm); NHM P 13186, articulated posterior half of individual in part (EBL: 10 cm); NHM P 13186, articulated caudal portion of individual in part (EBL: 10 cm). Additional material: GSE 2143, articulated anterior portion of individual, including skull (EBL: 3 cm); NHM P 14562, incomplete articulated individual in part (EBL: 6 cm); NHM P 14564, nearly complete articulated individual in part (EBL: 9 cm); NHM P 61546, incomplete articulated individual in part with trunk squamation and skull (EBL: 8 cm); NHM P 61549, complete articulated individual in part (EBL: 10 cm); NHM P 61002, incomplete articulated individual in part with trunk squamation, paired fins, and posterior skull (EBL: 10.5 cm); NHM P 13181 (part) and NHM P 14561 (counterpart), incomplete articulated anterior third of individual (EBL: 12 cm); NHM P 61548, nearly complete articulated individual in part and counterpart (EBL: 12 cm); NMS 1980.40.30, National Museums of Scotland, Edinburgh, Scotland, UK, articulated postcranium of individual in part and counterpart (EBL: 4 cm); NMS 1965.4.2, nearly complete articulated individual in part (EBL: 5 cm); NMS 1965.4.2, articulated postcranium of individual in part (EBL: 5.5 cm); NMS 1980.40.27, articulated postcranium of individual in part and counterpart (EBL: 6.5 cm); NMS 1965.4.3, nearly complete articulated individual in part and counterpart (EBL: 7 cm); NMS 1956.5.1, incomplete articulated individual in part and counterpart (EBL: 7.5 cm); NMS 1984.67.61, nearly complete articulated individual in part (EBL: 7.5 cm); NMS 1984.67.63, nearly complete articulated individual in part and counterpart (EBL: 9 cm); NMS 1980.40.31, nearly complete articulated individual in part (EBL: 9.5 cm); NMS 1984.67.65, nearly complete articulated individual in part and counterpart (EBL: 9.5 cm); NMS 1984.67.64, incomplete anterior two-thirds of individual in part (EBL: 11 cm); NMS 1984.67.62, nearly complete articulated individual in part, lacking axial lobe (EBL: 11.5 cm); GLAHM V 8327, Hunterian Museum, Glasgow, Scotland, UK, nearly complete articulated postcranium of individual in part (EBL: 8 cm). Type localities and horizon: River Tweed below Coldstream, Berwickshire, Scotland, UK. Calciferous Sandstone Series, Cementstone Group, Schopfites claviger-Auroraspor macra (CM) miospore biozone (348 – 347 Mya; Smithson et al., 2012), Tournasian 3 (TN 3) zone, Ivorian regional substage, Dinantian regional stage, late Tournaisian stage, Mississippian subsystem, Carboniferous system (Traquair, 1881; Gardiner, 1985; Smithson et al., 2012). Other localities and horizons: Foulden Fish Bed, Foulden Burn, Berwickshire, Scotland, UK. Calciferous Sandstone Series, Cementstone Group, CM biozone, TN 3 zone, Courceyan regional substage, Dinantian regional stage, late Tournaisian stage, Mississippian subsystem, Carboniferous system (White, 1927; Gardiner, 1985; Wood & Rolfe, 1985; Dineley & Metcalfe, 1999; Smithson et al., 2012); Coomsden Burn, Redewater, Northumberland, England, Cementstone Group, Dinantian regional stage, late Tournaisian stage, Mississippian subsystem, Carboniferous system (White, 1927; Moy-Thomas, 1938; Gardiner, 1985). Diagnosis (emended from Traquair, 1881): As for genus. Remarks: The genus Fouldenia includes all specimens from Foulden previously assigned to Styracopterus (Moy-Thomas, 1937; Gardiner, 1985), as well as specimens from the Calciferous Sandstones at Coldstream originally attributed to Holurus ischipterus, subsequently to S. ischipterus (or ‘ ischypterus’), and finally to S. fulcratus (Traquair, 1881, 1890; Moy-Thomas, 1937; Gardiner, 1985). The Coldstream specimens are here found to be indistinguishable from juveniles of Fouldenia, as originally predicted by Moy-Thomas (1937), and are thus reassigned to the latter taxon. The older name for the single known species within Fouldenia is therefore ischipterus (Traquair, 1881), not ottadinica. This has been corrected to ischiptera to agree with the gender of the genus. Likewise, the appropriate holotype for Fouldenia is GSE 2187, as designated for Holurus ischipterus by Traquair (1881), rather than NHM P 13178 as proposed for Fouldenia by White (1927).	en	Sallan, Lauren Cole, Coates, Michael I. (2013): Styracopterid (Actinopterygii) ontogeny and the multiple origins of post-Hangenberg deep-bodied fishes. Zoological Journal of the Linnean Society 169 (1): 156-199, DOI: 10.1111/zoj.12054, URL: http://dx.doi.org/10.1111/zoj.12054
824287C58038FF858952FCD7B5C6FA84.taxon	description	DESCRIPTION Skull The construction of the skull of Fouldenia is largely as illustrated by White (1927) and Gardiner (1985), but there are several discrepencies. Starting at the anterior end, Fouldenia bears an elongate, nearly erect median rostral, featuring sigmoidal lateral margins (Figs 5 – 7, 13). The rostral exhibits a slight curve in smaller specimens, but is significantly inclined halfway along its length in larger individuals, where it is ornamented with wide, horizontal ganoine bands (Figs 7 B, 13 D). The elongate, curved nasals of Fouldenia are bounded by the premaxilla and lachrymal ventrally, and frontal and dermosphenotic dorsally (Figs 5 C, D, F, G, 6 C, 7 C, D, E). The nasal widens towards the gape and does not exhibit marginal indentitions for the nostrils, contrary to Gardiner’s (1985) reconstruction. In the smallest specimens of Fouldenia (e. g. NHM P 14562; Fig. 5 B), the frontals and parietals are relatively wide and nearly equal in size, but in larger fish (e. g. NHM P 13181; Fig. 7 D) the frontals appear longer and narrower. These are joined at a diagonal suture line formed by the posterolateral processes on the frontals. The supraorbital canal runs through the lateral midline of these bones, and the mesial surface of the canal is apparent in the holotype NHM P 13178 (Fig. 6 B) and NHM P 61549 (Fig. 6 H). Frontal ornament consists primarily of horizontal striations, although a curved ridge at the midpoint marks a granulated or wavy posteromedial ornament field in both NHM P 14562 (Fig. 5 B) and NHM P 13181 (Fig. 7 D). The parietal ornament consists of intercalating wavy ridges laterally and more longitudinal bands dorsally, as is apparent in NHM P 13179, NHM P 13180, and NHM P 13181 (Figs 5 F, G, 7 D). The dermopterotic is more like that described by White (1927) than Gardiner’s (1985) reconstruction; the posterior portion is wide and the margins are smooth (Figs 5 – 7). The lateral margin curves to form an anterior point. This margin sits at the level of the curved ridge on the frontal in NHM P 14562 (Fig. 5 B) and NHM P 13181 (Fig. 7 D), whereas the straight posterior margin contacts the extrascapular. This spatial relationship appears fixed in individuals of all sizes. Fouldenia possesses one pair of rectangular extrascapulars (Figs 5 B, F, D, 6 A, C, F, B, 7 D) that sit at the level of the anterior margin of the opercular series, ornamented with short horizontal striations. The post-temporal is wide with a diagonal posterior margin. Although the general form is blunt and rounded in smaller fish (e. g. NHM P 14562, NHM P 13179, NHM P 13180; Fig. 5 B, F, G), it tapers to a rounded lateral point in larger specimens (e. g. NMS 1984.67.64, NHM P 61002, NHM P 61548; Fig. 7 A, B, D). The post-temporal is also long, extending past the opercular series. The orbit in Fouldenia is bounded by the nasal, the dermosphenotic, and two infraorbitals (the lachrymal and jugal), but not by the premaxilla as described by Gardiner (1985). The dermosphenotic is ornamented with horizontal ridges (Fig. 6 C) and stretches from the nasal to the preoperculum, leaving little room for any unobserved supraorbitals or suborbitals. In specimens under 7 cm in total length (e. g. NHM P 14562 and NMS 1965.4.3; Fig. 5 B, C), the dermosphenotic is a homogenous, thick crescent, whereas in larger specimens (e. g. NHM P 14564 and NMS 1984.67.64; Figs 6 C, 7 C) it features a distinct rectangular ventral portion and an elongated anterior process. Contrary to the previous description by Gardiner (1985) and coding for a t-shaped dermosphenotic by Gardiner & Schaeffer (1989), there is no evidence for a distinct posterior process (NHM P 14562, NMS 1965.4.3, NMS 1956.5.1, and NHM P 14564; Figs 5 B, C, D, 6 C). The jugal is unfortunately incomplete in specimens of Fouldenia, but largely conforms to that described by Gardiner (1985). It forms a thick arch extending from the dermosphenotic to the midpoint of the orbit in NMS 1984.67.65 and NHM P 13179 (Figs 5 F, 6 F), and widens with size (NHM P 61548 and NHM P 13181; Fig. 7 D, E). It is not clear if the horizontally ridged ornament in NMS 1965.4.3, NHM P 13181, and NHM P 61548 (Figs 5 C, D, 7 E) has any relationship with a branching suborbital canal, as in Amphicentrum (Coates, 1988). The lachrymal is rectangular and meets the premaxilla and nasal at an anterior margin that is blunt in small individuals (NHM P 14562; Fig. 5 B), but is tapered in the largest specimens (NHM P 13181; Fig. 7 D). Jaws and dentition A badly preserved palatoquadrate is found in NHM P 13183 (Fig. 6 A), but little can be determined about the morphology. The dorsal surface of the parasphenoid is fairly wide in NMS 1984.67.65 (Fig. 5 E), with a shallow central depression and lateral margins marked by prominent ridges that might represent parabasal canals. The bone is laterally thick in NHM P 13180 (Fig. 5 G) and NMS 1984.67.65 (Fig. 6 E), widening towards the posterior wall of the orbit. Phylogenetically important information concerning the extent and condition of the ascending process remains unknown (Patterson, 1982; Gardiner & Schaeffer, 1989; Coates, 1999). The maxilla is well preserved in nearly all specimens of Fouldenia and overlaps the mandible, particularly a rounded posteroventral process. The maxilla features a rounded, triangular posteriorly expanded portion and a rectangular anterior ramus ending in a blunt margin. In the smallest individuals (e. g. NMS 1980.40.30 and NHM P 14562; Fig. 5 A, B), the two portions are nearly equal in height to the premaxilla, and the bone features rounded, edentulous ventral margins, as best shown in NHM P 13180 and NMS 1984.67.62 (Figs 5 G, 7 C). The premaxilla bears rounded lateral processes that sit above the maxillae (Figs 7 C, 13), but these are less prominent than reconstructed by Gardiner (1985), and do not contact the orbit. The surangular is not visible in any specimen of Fouldenia, and there appears to be little room for such a bone between the dentary and angular. The dentary is robust in specimens over 10 cm in total length (Fig. 7), expanding dorsally such that the symphysial margin is diagonal and the jaw margin is prominent. In smaller specimens (Fig. 5), a more gracile, blunt dentary is almost entirely overlapped by the maxilla. The crescent-shaped angular in Fouldenia (Figs 5 D, G, 6 A, F, G) is obscured by the maxilla in smaller specimens, as described by White (1927) and Gardiner (1985). However, it extends posteriorly in larger fish (e. g. NHM P 13185, NHM P 14562, and NMS 1984.67.65; Figs 6 B, C, 7 B), with its juncture with the quadratojugal exposed. Bands of smooth ganoine sit parallel with the jaw margins in all specimens, and the prominence of these is apparent in NHM P 14564 (Fig. 6 C), NHM 1984.67.65 (Fig. 6 E), NHM P 61549 (Fig. 6 G), NHM 1984.67.64 (Fig. 7 B), and NHM P 61548 (Fig. 7 E). The smallest specimens (e. g. NMS 1980. 40.30 and NHM P 14562; Fig. 5 A, B) have a single rectangular tract on each side of the gape. This increases to two maxillary and three mandibular bands in mid-sized individuals, such as NHM P 13179 (Fig. 5 F), with an additional tract added along the anterodorsal margin of the maxilla in larger individuals like NMS 1984.67.65 (Fig. 6 E). In the largest specimens of Fouldenia (e. g. NMS 1984.67.64; Fig. 7 B), the bands are fused and intercalated, joined by shorter segments of ornament, forming a solid enameloid ‘ beak’. Similar ganoine cover is found in Styracopterus (see above) and the Visean styracopterid Benedenius (Van Beneden, 1871; Traquair, 1877 – 1914, 1878; De Koninck, 1878; Moy-Thomas, 1937; L. C. S., pers. observ.; Appendix S 1), as well as the Cheirodopsis, Amphicentrum, Paramesolepi s, and Eurynotus, albeit without distinct bands (L. C. S., pers. observ.; Appendix S 1; Fig. 15). A line of tiny holes in the dentary ornament marks the mandibular canal in NMS 1984.67.64 (Fig. 7 B), as do similar openings in Eurynotus (NMS 1957.1.5686; L. C. S., pers. observ.), Amphicentrum (Coates, 1988), and Styracopterus (L. C. S., pers. observ.). The rest of the maxilla is ornamented with concentric ridges at the margins (as in NMS 1984.67.65; Fig. 6 E) and a distinct field of lateralized wavy ridges at the centre of the posterior portion. The angular in Fouldenia is almost completely covered by enameloid patches in fish over 9 cm in total length, such as NMS 1984.67.65, NHM P 61002, and NMS 1985.67.64 (Figs 6 F, 7 A, B, 13 C, D), yet is naked in smaller individuals. The gape in all specimens of Fouldenia appears edentulous in lateral aspect. White (1927) described and illustrated small, blunt teeth from the posterior portion of the dermal mandible in NHM P 13183 (Fig. 6 A). These possess flat, bulbous crowns and thin waists (Fig. 14), resembling the pediculate dentition of the Palaeozoic actinopterygians Mesolepis (Traquair, 1879; Boulenger, 1902; Coates, 1988; L. C. S., pers. observ.; Appendix S 1), Eurysomus, as illustrated by Traquair (1879: pl. IV; fig. 6.5), and Benedenius, as described by Boulenger (1902). Given the position of these ‘ teeth’ in the Fouldenia specimen NHM P 13182 – 3 (Fig. 6 A), away from the dentary and just ventral to the palatoquadrate, they are likely associated with coronoid-derived mandibular tooth plates like those found in Styracopterus and other eurynotiform fishes (Moy-Thomas & Miles, 1971; Coates, 1988; L. C. S., pers. observ.; Appendix S 1; Fig. 14). There is also evidence for an upper jaw dentition obscured from lateral view. In NHM P 61549 (Fig. 6 G), a homogeneous set of closely situated, small round elements is exposed by a gap in the anterior ramus of the maxilla. In NMS 1984.67.61 (Fig. 5 E), tall cylindrical teeth with expanded crowns are found in the same area, with roots attached to what is either the mesial surface of the maxilla or reinforced palatal bones. NMS 1980.40.31 (Fig. 6 D) has imprints of tooth or denticle bases overlying an impression of the maxilla and remnants of ganoine ornamentation. These teeth are positioned similarly to the maxillary dentition found in Amphicentrum and Styracopterus, but may also be associated with ectopterygoid-derived tooth plates, as in the same taxa (Bradley Dyne, 1939; Coates, 1988; L. C. S., pers. observ.; Appendix S 1). In light of the mandibular tooth plate denticles in NHM P 13183, it is probable that Fouldenia possesses both maxillary teeth and palatal tooth plates (Fig. 14), but the fossil evidence and / or morphological similarity prevents definite differentiation. The jaws of Fouldenia are supported by a nearly vertical suspensorium, as reconstructed by Gardiner (1985). The hyomandibula is exposed in a number of individuals of different sizes, including NMS 1980.40.30, NHM P 14562, NHM P 14564, and NMS 1985.67.64 (Figs 5 A, B, 6 C, 7 B). The thick hyomandibula features an expanded dorsal head located near the dermopterotic, as in Amphicentrum (Bradley Dyne, 1939), and covered laterally by a teardropshaped dermohyal with an ornament of vertical ridges (Figs 6 G, 7 B). Whereas the hyomandibula is nearly straight in smaller specimens (e. g. NMS 1980.40.30; Fig. 1 A), it exhibits a high degree of curvature in the large individuals listed above. The preoperculum in Fouldenia, best preserved in NMS 1980.40.30, NHM P 13180, NHM P 14564, and NHM P 61002 (Figs 5 A, G, 6 C, 7 A), is tall with an indistinct dorsal arm ending near the skull roof and a thick posteroventral process to the quadratojugal. The anterior margin is shallowly curved, whereas the posterior margin mirrors the hyomandibula and is lined by a wide ridge. A horizontal pit line is visible just above the maxilla in many specimens (e. g. NHM P 61002, NHM P 13180, NHM P 13179, NMS 1956.5.1, and NMS 1985.67.64; Figs 5 D, F, G, 7 A, B), and bisects the ornament into a ventral field of vertical ridges and a dorsal field of horizontal and inclined lines (see NHM P 14564 and NHM P 61002; Figs 6 C, 7 A). Opercular series The operculum of Fouldenia is similar to that reconstructed by White (1927), in that it is slightly inclined with a rounded apex just under the extrascapular and a sigmoidal ventral margin at the level of the horizontal pitline (see NMS 1984.67.64, NHM P 13179, NMS 1980.40.30; Figs 5 A, F, 7 B). The bone is wider and much less tapered in individuals over 8 cm (Figs 6, 7), so that it appears more plate-like than ovoid. The ornamentation consists of intercalated diagonal ridges running posteroventrally, as seen in NHM P 61002 (Fig. 7 A). The suboperculum of Fouldenia is largely rectangular in NHM P 61002 (Fig. 7 A). It extends ventrally to the quadratojugal and posteriorly to the level of the post-temporal. The posterior margin is slightly rounded, whereas the ventral margin is sigmoidal, bearing an anteroventral process reaching towards the jaw joint, as originally illustrated by White (1927; Figs 6 E, 7 A, 13) and also found in other styracopterids, eurynotiforms, and the Palaeozoic taxa listed in the description of Styracopterus (L. C. S., pers. observ.; Appendix S 1). Like the other styracopterids (L. C. S., pers. observ.; Appendix S 1), the ornamentation of the suboperculum in NHM P 13180 (Fig. 5 G) and NHM P 61002 (Fig. 7 A) is divided: the ganoine ridges on the process and near the ventral margin are posteroventrally diagonal, whereas the ornamentation elsewhere radiates horizontally or dorsally from the anterior margin of the bone. Gulars and branchiostegals	en	Sallan, Lauren Cole, Coates, Michael I. (2013): Styracopterid (Actinopterygii) ontogeny and the multiple origins of post-Hangenberg deep-bodied fishes. Zoological Journal of the Linnean Society 169 (1): 156-199, DOI: 10.1111/zoj.12054, URL: http://dx.doi.org/10.1111/zoj.12054
824287C58038FF858952FCD7B5C6FA84.taxon	description	The inclined, rounded supracleithrum in Fouldenia extends to a pointed margin near the midline of the suboperculum (Fig. 7 B). There is no evidence of the course of the posterior lateral line, as it is likely to be obscured by the dense, vertical ganoine ridges spread out around the midline in NHM P 61548 (Fig. 7 B). Neither White (1927) nor Gardiner (1985) described postcleithra in Fouldenia, but a single postcleithrum is preserved in NMS 1984.67.62, NMS 1984.67.65, NHM P 61549, and NHM P 13180 (Figs 5 C, G, 6 E, G). This is similar to the postcleithra in Paramesolepis (Moy-Thomas & Bradley Dyne, 1938), Amphicentrum (Coates, 1988), and Styracopterus (L. C. S., pers. observ.; Appendix S 1), in that it is long with rounded margins and ends around the first branchiostegal. The cleithrum in Fouldenia is inclined posteriorly, and bears a broadly crescentic dorsal process with a pointed dorsal limit and a rounded posterior process underlying the pectoral fin insertion. (Figs 5 A, B, E, 6 B, 7 A), as in other Foulden actinopterygians (White, 1927; Moy-Thomas, 1938; Gardiner, 1985; L. C. S., pers. observ.; Appendix S 1). The cleithrum is ornamented with vertical stripes of ganoine that mirror the curved posterior margin. A process of the endoskeletal shoul- der girdle is exposed where the cleithrum curves around the point of pectoral fin insertion in NHM P 14562 (Fig. 5 B) and NHM P 61546 (Fig. 5 H), and is covered with longitudinal ridges distinct from any nearby dermal ornament. The cleithrum joins with the laterally convex posterior margin of the clavicle at the level of the opercular series in NMS 1984.67.62 (Fig. 7 C) and NMS 1984.67.65 (Fig. 6 F). The morphology of the clavicle is largely obscured, but it appears very thick (as discussed above) and somewhat triangular in the lateral dimension in NMS 1984.67.61, NHM 1984.67.65, NHM P 61002, and NHM P 14564 (Figs 5 E, 6 C, F, 7 A). Paired fins The pectoral fin is situated near the ventral body margin and has a nearly vertical insertion into the shoulder. The fin is supported by at least six radials: posterior / ventral radials preserved in NHM P 61002 (Fig. 8 J) and NMS 1984.65.61 (Fig. 8 C) are elongate, with narrow, somewhat overlapped proximal ends and rounded distal portions. The middle of each radial in NHM P 61002 (Fig. 8 J) consists of a narrow cylindrical body with a thin ventral flange. GLAHM V 8327 (Fig. 8 E) shows the squat anterior / dorsalmost radials, which sit in a shorter space between the primary fin rays and the dermal shoul- der. The presumptive propterygium is surrounded by fin rays, as is diagnostic for actinopterans (Coates, 1999; Gardiner et al., 2005). The difference in length between the anterior and posterior radials matches the diagonal orientation of lepidotrichial bases in NHM P 13183, GLAHM V 8327, and NHM P 14564 (Fig. 8 F, G), an arrangement found in other early actinopterygians such as Mimipiscis (Choo, 2011) and Styracopterus (L. C. S., pers. observ.; Appendix S 1). As noted by White (1927), no specimen of Fouldenia exhibits a complete pectoral fin, obscuring its exact shape. The proximal fins in GSE 2143, GLAHM V 8327, NHM P 13183, and NHM P 14564 (Fig. 8 A, E, F, G) suggest that it was wide-based with a slightly curved anterior margin lined by fringing fulcra that are barely distinguishable from lepidotrichial terminals. The lepidotrichia are thin, cylindrical, and densely packed, with long segments throughout their length. Thus, the pectoral fin more closely resembles that of Phanerosteon ovensi (White, 1927; L. C. S., pers. observ.; Appendix S 1) and the Visean Tarrasius (Sallan, 2012), than Styracopterus. Only a handful of specimens have incomplete pelvic fins. The curved anterior edge is preserved in NMS 1984.67.61 (Fig. 8 D), with an unsegmented primary fin ray and further lepidotrichia similar to those of the pectoral fin. Large, leaf-shaped fringing fulcra are differentiated from lepidotrichial terminals by linear central furrows. Two large, ovoid basal fulcra overlap the leading edge of the pelvic fin in NMS 1984.67.65 (Fig. 8 I). These are ornamented with concentric, longitudinal striations that fuse at the posterior margin. The size of the fin base is restricted by the short distance between the pelvic and anal basal fulcra in all fish, even though the position of the pelvic fin changes with size (Fig. 13). In the 4 - cm individual NMS 1980.40.30, the pelvic fin is situated near the distal pectoral fin, whereas in larger specimens, such as NMS 1984.67.65, it originates posterior to the body midline (Fig. 8). Median fins The dorsal fins in the largest specimens of Fouldenia are as described by White (1927): tall and superficially triangular, with the peak in the posterior half of the fin. In these individuals (e. g. NHM P 61548 and NHM P 61549; Fig. 9 E, F), the anterior margin of the dorsal fin and leading lepidotrichia are straight, and the fin originates in the posterior portion of the body (Fig. 13 C, D). In the smaller specimens NMS 1980.40.30, NMS 1980.40.27, and NMS 1965.4.3 (Fig. 9 A, B, C), the dorsal fin is rounded with curved lepidotrichia held nearly parallel with the body axis, and originates at the midpoint of the trunk, opposite the pelvics and well before the anal fin (Fig. 13 A, B). Robust, erect basal fulcra sit against the dorsal lepidotrichia. Disarticulated fulcra in NMS 1980.40.31 (Fig. 9 D) exhibit needle-like distal processes with paired cylindrical ridges separated by a deep furrow, bounded ventrally by rounded plates with concentric ornament. The primary dorsal lepidotrichia are thick and unsegmented, presenting a spine-like form when combined with the elliptical fringing fulcra (Fig. 9). The remaining lepidotrichia have rounded bases and short plate-like segments with cylindrical anterior ridges. The anal fin in Fouldenia is very similar to the dorsal fin, with the first few lepidotrichia likewise consolidated into ‘ spines’, a feature readily apparent in NMS 1965.4.3 (Fig. 10 C, D). Anal basal fulcra in NMS 1984.67.62 and NHM P 61548 (Fig. 10 I, J) are evocative of their dorsal equivalents and those of Styracopterus (see above). However, more anterior basal fulcra in this series of four or five are thick and rounded like the dorsal ridge scales. The anal fin base extends to the base of the caudal peduncle. Like the dorsal fin, the anal fin is rounded in smaller specimens such as GSE 2187 (Fig. 10 B) and NHM P 13183. The anterior margin remains curved in the largest fishes, whereas the posterior margin is deeply concave (e. g. NHM P 13183), resulting in a superficially half-crescent form in NHM P 61548 (Fig. 10 J). Tail and caudal fin The caudal region of Fouldenia comprises over a third of the total body length in the smallest specimens (e. g. NMS 1980.40.30; Figs 11 A, 13 A) and a quarter in the largest (e. g. NHM P 61549; Figs 12 D, 13 D). As described by White (1927), the tail consists of a thick caudal peduncle, a deep yet shallowly cleft caudal fin, and a very long, tapering axial lobe extending beyond the fin. The dorsal surfaces of the peduncle and axial lobe are covered by enlarged basal fulcra that, as preserved in NHM P 13183 and holotype NHM P 13178 (Fig. 12 A, B), are identical to the dorsal fin basal fulcra in NMS 1980.40.31 (Fig. 9 D). The posteriormost basal fulcra on the ventral surface of the peduncle in NMS P 13183 (Fig. 12 A), originally illustrated by White (1927), are nearly mirror images, except that the paired rami separate to form distinct points distally (Fig. 12 A), and are thus narrower versions of the same scales in Styracopterus. More posterior basal fulcra on both the peduncle and axial lobe are progressively shorter and have pointed apices, providing a highly overlapped, elliptical appearance in lateral view (Figs 11, 12). Prominent fringing fulcra line the entire ventral margin of the caudal fin in NMS 1965.4.2, NMS 1965.4.3, NMS 1980.40.31, and NHM P 13185 (Figs 11 A, F, 12 C, E). These are also elliptical, slightly overlapped, and sit perpendicular to the lepidotrichia. Fulcra appear as narrow spines with longitudinal furrows on the base of the axial lobes in NHM P 13183 and NMS 1965.4.2 (Figs 11 C, 12 A), becoming smaller and more inclined distally in GSE 2187, NMS 1965.4.3, and NHM P 13185 (Figs 11 C, F, 12 E). Fulcra in the second half of the series are paired in larger specimens (Fig. 12), a trait previously reported only in Cheirolepis (Gardiner, 1984), but also found along the distalmost tails of Styracopterus, Aesopichthys, and other Foulden fishes (L. C. S., pers. observ.; Appendix S 1). In fact, all the axial lobe fulcra are paired in smaller, probably juvenile individuals with relatively shorter axial lobes, such as NHM P 13187, NMS 1965.4.2, and NMS 1980.40.27 (Fig. 11 B, C, E), suggesting fusion during ontogeny in Fouldenia and perhaps other actinopterygians. The large specimens NMS 1980.40.31 and NHM P 13185 (Fig. 12 C, E) are the only individuals with complete axial lobes, which lack fulcra distal to the caudal fin. This arrangement is similar to that of the elongated axial lobe in the deep-bodied Serpukhovian genus Aesopichthys (Poplin & Lund, 2000; L. C. S., pers. observ.; Appendix S 1), as well as other styracopterids and Eurynotus (e. g. NMS 1878.18.12; Traquair, 1879; L. C. S., pers. observ.; Appendix S 1). Both NMS 1980.40.31 and NHM P 13185 (Fig. 12 C, E) bear remnants of a distinct epichordal fin around the distalmost tail. Lepidotrichia found along the ventral surface of the posteriormost axial lobe differ from the caudal lepidotrichia in their tapering morphology, and originate after a considerable gap. The first few lepidotrichia of the caudal fin are consolidated and bear elongated fringing fulcra like their equivalents in the median fins (Figs 11, 12). Likewise, the remaining rays in the ventral lobe have plate-like segments with anterior ridges and taper to a point (Figs 11, 12). The bases of ventral lobe lepidotrichia are distinctly thick and wide in NHM P 61548 (Fig. 12), giving the appearance of an extended peduncle. Lepidotrichia in the dorsal lobe originate from the axial lobe in NHM P 13185, NHM P 61549, and NMS 1980.40.31, and are similar to the paired fin rays in their thin, cylindrical morphology. These apparently lack bifurcation, although most are truncated at their distal extremities. The overall appearance of the tail and caudal fin varies between size classes. Small individuals have long peduncles that exhibit a gradual, not well marked, transition into a thin axial lobe (Figs 11, 12, 13 A, B). Their long caudal fins exhibit shallow clefts and small, narrow fringing fulcra. In contrast, the largest individuals, such as NHM P 61548 and NHM P 13183 (Fig. 12 E, F), have tall peduncles with nearly vertical posterior margins and a marked transition into a wide-based, distally tapering axial lobe. Caudal fins have deep clefts and are equilobate, and feature robust fringing fulcra. The terminus of the lateral line changes along with the morphology. In the 5 - cm individual NMS 1965.4.2 (Fig. 11 C), the lateral line curves parallel with the posterior margin of the caudal peduncle as it approaches the end of the body, turning onto the midline of the axial lobe. In the 12 - cm fishes NHM P 13185 and NHM P 61548 (Fig. 12 E, F), the lateral line is largely horizontal, and appears to end on the caudal fin just ventral to the base of the axial lobe, but may continue at the caudal fin base. Squamation The largest individual of Fouldenia, NHM P 61548 (~ 12 cm EBL), has 51 sigmoidal scale rows from the skull to the peduncle, with up to 34 scales from the dorsal ridge to the anal midline. However, individuals under 6 cm in length have significantly fewer scales: NMS 1965.4.2 (5 cm EBL) has approximately 34 rows of up to 25 scales. The slightly longer NMS 1965.4.6 (5.5 cm EBL) has around 40 rows, whereas NMS 1980.40.27 (6.5 cm EBL) had almost the maximum number of rows, although the number of scales per row remains at 25. The larger NMS 1984.67.61 (7.5 cm EBL) has 30 scales per row at maximum body depth. Fish of 8 – 9 cm in total length, such as NHM P 61002 and NMS 1984.67.63, have approximately the same counts as the largest specimen. Thus, scale counts increase with body size primarily through the generation of rows up to the midpoint of the observed growth series, at which point addition at the margins and increases in scale height cover changes in body area. In smaller specimens of Fouldenia, such as GSE 2143 (3 cm EBL), NMS 1980.40.30 (4 cm EBL), NMS 1965.4.6 (5.5 cm EBL), NHM P 14562 (6 cm EBL), and GSE 2187 (6 cm EBL), all scales are small and acuminate, with smooth margins (Fig. 14 A, B), and bear two longitudinal bands of smooth ganoine. These are identical to the scales found on the smallest specimens of the co-occurring Aetheretmon (NHM P 61006; L. C. S., pers. observ.). Like Aetheretmon, the smallest Fouldenia individuals, such as NMS 1980.40.30 (Fig. 9 A), lack scales around the bases of their median fins. This suggests that squamation first developed around the lateral line in these fishes, just as it does in living teleosts (Koumoundoros, Divanach & Kentouri, 2001). Juvenile scales develop near the dorsal and ventral midlines and are retained on the posterior half of specimens NMS 1965.4.3, NMS 1984.65.61, and NMS 1956.5.1, which range from 7 to 7.5 cm in estimated body length, and have greater body depths anteriorly (Fig. 13 C). In individuals over 8 cm in length [e. g. NHM P 13178 (9 cm EBL), NMS 1984.67.65 (9.5 cm EBL), NHM P 61502 (10 cm EBL), NMS 1984.67.65 (11 cm EBL), and NMS 1984.67.65 (11 cm EBL); White 1927; Fig. 13 C], ‘ juvenile’ scales are limited to an anterior ventral field around the pectoral fins and clavicle. The largely scaleless actinopterygian Phanerosteon (e. g. NMS 1970.26.27; L. C. S., pers. observ.; Appendix S 1), found at both Foulden and Glencartholm, exhibits rows of small scales in the same area (White, 1927; Gardiner, 1985). Scale rows in this region in Amphicentrum and Benedenius have a different orientation from those on the rest of the flank (Traquair, 1878, 1879; L. C. S., pers. observ.; Appendix S 1). This anterior ventral field (or pectoral peduncle; Sire & Arnulf, 1990) might represent a distinct region of scale development in some early actinopterygians, just as it does in some living teleosts (Koumoundoros et al., 2001). In individuals larger than 8 cm in length, such as NMS 1984.65.61 and NHM P 13182 (Fig. 13 C, D), rhomboid scales on the anterolateral flank have smooth margins and exhibit four or more posteroventrally diagonal bands of ganoine. The scales in larger fish (e. g. NHM P 61546) are taller and feature a more complex ornament of diagonal ganoine bands that fuse in nested fashion towards the posteroventral corner and a stripe lining the posterior margin. This ornamentation is repeated vertically on the taller, more rectangular anterior flank scales of the larger specimens. A small notch on the posterior margin marks the transition between ornamentation fields, giving the bilobate appearance described by White (1927) and the impression of scale fusion. Scales on the posterior flank of fish over 8 cm (e. g. GLAHM V 8327 and NHM P 13182) are shorter and horizontally elongated (Fig. 13 C, D), yet exhibit a rhomboid shape and ornamentation similar to the more anterior squamation. In specimens over 10 cm in total length, these scales have the same relative height and morphology as anterior flank scales in 8 - cm fish (Fig. 13 C, D). In large specimens of Fouldenia, the lateral line scales are taller than other members of the same row, but are otherwise indistinguishable apart from a raised cylindrical bump that bisects the ornament horizontally (Fig. 13 C, D). The lateral line runs from the level of the supracleithrum to the midline of the caudal peduncle in the largest specimens (Figs 12 F, 13 D). The diverse flank scales in Fouldenia are similar in shape and ornament to various iterations in the Permian taxon Acrolepis sedgwicki Agassiz, 1833 – 1844, as first illustrated by Agassiz (1833 – 1844; NHM P 553; L. C. S., pers. observ.; Appendix S 1), which is a large marine fusiform actinopterygian that diverges from Fouldenia in most other non-plesiomorphic traits. All specimens over 8 cm in length possess a distinct ‘ hinge line’ in the peduncle squamation, marking the transition between scales with vertically directed pegs and those with posteriorly directed pegs, a trait found in many other early actinopterygians (Patterson, 1982; Gardiner & Schaeffer, 1989; Coates, 1998, 1999; Figs 12 F, 13 C, D). Peduncle rows on both sides of the hinge line contain small rhomboid scales fully covered in ganoine and featuring an anterior ridge (Figs 12 D, 13 C, D). These resemble the microsquamation present on the entire tail surface of Tarrasius (Sallan, 2012; L. C. S., pers. observ.; Appendix S 1). Scales on the proximal axial lobe and along the base of the caudal fin are diamond shaped, whereas the more distal squamation consists of very small elliptical scales resembling the ‘ juvenile’ flank scales (Figs 12 D, 13). Fouldenia specimens over 8 cm in length possess prominent dorsal ridge scales that run from the nape to the dorsal fin basal fulcra (White, 1927; Fig. 13 C, D). They are highly overlapped: each has a triangular furrow on the anterodorsal surface to hold the distal end of their neighbour. The anteriormost ridge scales are squat with rounded margins and slightly pointed apices, and feature longitudinal striations. Ridge scales in the posterior half of the series are longer, wider, and vertically oriented, and exhibit more robust ornamentation. The last few ridge scales are thinner and have distal processes like the dorsal basal fulcra, and are similarly erect and overlapped. Thick ganoine ridges on these scales run parallel with the body axis. Thus, the transition between the last two dorsal ridge scales, the basal fulcra, and the primary lepidotrichia appears gradual (Fig. 13 C, D).	en	Sallan, Lauren Cole, Coates, Michael I. (2013): Styracopterid (Actinopterygii) ontogeny and the multiple origins of post-Hangenberg deep-bodied fishes. Zoological Journal of the Linnean Society 169 (1): 156-199, DOI: 10.1111/zoj.12054, URL: http://dx.doi.org/10.1111/zoj.12054
