taxonID	type	description	language	source
03C287AAFFFD0B05FF357869FE4EFE80.taxon	description	Samples: GU 66 F- 4 Dimensions: long axis 71 – 74 µm, short axis 41 – 45 µm	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFD0B05FF357869FE4EFE80.taxon	diagnosis	Diagnostics: Distinctively shaped, lens-shaped in valve view but the frustules wedge-shaped (cuneiform) because the valve faces are at an angle to one another. Areolae with a series of radiating patterns around the margin, especially on the more strongly curved side. Large rimoportulae visible in the oblique view. A pseudonodulus is present on the flatter side.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFD0B05FF357869FE4EFE80.taxon	discussion	Comments: Two valves observed in one sample. The ventral curvatures of A. cuneiformis vary from straight to sinuous and Hustedt (1927 – 1931) combined several older Eudotia species as varieties. Although Round et al. (1990) say that the valves are cuneiform, it seems to us that Wallich’s (1860) epithet refers to the shape of the frustule (described by Round et al. 1990 as “ shaped like orange segments ”), rather than to the shape of the valve. The genus Hemidiscus was subsumed into Actinocyclus by Gómez et al. (2017); they did not discuss any varieties of H. cuneiformis but their images, like ours, conform to var. ventricosa (Castracane) Hustedt. We have therefore omitted any varietal designation.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFE0B05FF357C5DFD38FD23.taxon	description	Samples: GU 55 B- 5 Dimensions: Length 30 µm, width 12 µm, stria density 8 in 10 µm (dorsal) and 13 in 10 µm (ventral)	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFE0B05FF357C5DFD38FD23.taxon	diagnosis	Diagnostics: More strongly and coarsely striated on the dorsal surface, dorsal striae often biseriate and bifurcating towards the sternum, ventral striae uniseriate.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFE0B05FF357C5DFD38FD23.taxon	discussion	Comment: Our specimens (seen also in Yap and Palau) are much shorter than the 68 – 129 µm given by Levkov (2009). A Palauan specimen (Fig. 4) seen in SEM shows that the striae are mostly biseriate, the bifurcations resulting from the two rows diverging; these images conform to the specimens shown by Levkov in SEM.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFE0B04FF357E09FAE1FE7D.taxon	description	Dimensions: Length 27 – 45 µm, width 7 – 8 µm; dorsal striae 36 in 10 µm in the middle increasing to 39 toward the apices, ventral striae 38 in 10 µm.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFE0B04FF357E09FAE1FE7D.taxon	diagnosis	Diagnostics: Valves and copulae frequently forming a hyaline oval pattern in LM. In SEM, more prominent elongated areolae on either side of the dorsal rib with the rest of the dorsal striae comprising small areolae; prominent conopea at the central raphe endings.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFE0B04FF357E09FAE1FE7D.taxon	discussion	Comments: As far as we can tell from the SEM illustrations of valves in Podzorski & Håkansson (1987) and Stepanek & Kociolek (2018), the same species is being described and therefore the former name has priority. Although clearly shown in SEM by Stepanek & Kociolek (2018), they did not include a written description of ultrastructure. Podzorski & Håkansson (1987), although showing SEMs, also did not specify stria densities. Our SEM images show dorsal striae of irregular transapical slits, ending with a long, prominent slit at valve margin, mantle sharply delimited by a ridge and bearing a similar series of prominent slits (Figs 6, 7). Small central area on dorsal side of central nodule, and central striae somewhat more prominent. Ventral valve face with single row of slit-like areolae, interrupted by a conopeum developed ventrally and the ventrally deflected raphe. Internally, as shown in Stepanek & Kociolek (2018, pl. 8, fig. 4) the proximal raphe endings are straight. The girdle bands have a single line of slits along the narrow ventral part and faint striae on the wide dorsal part (Fig. 7 arrow). The lack of a ventral raphe ledge is indicative of Halamphora rather than Amphora, as summarized by Stepanek & Kociolek (2018, pp. 8 – 9 vs 28 – 29), but the broad girdle bands are indicative of Amphora. Neither Podzorski & Håkansson (1987) nor Stepanek & Kociolek (2018) showed girdle bands. Their materials were, respectively, from Palawan (Philippines) and Florida Keys. These fairly large, hyaline frustules resemble Halamphora hyalina (Kützing) Rimet & R. Jahn (Rimet et al. 2018) and Halamphora pseudohyalina (Simonsen) Stepanek & Kociolek (2018) (neither yet recorded from our region) in the presence of the distinct central area and a ventral surface; H. pseudohyalina has fine dorsal striae 28 – 30 in 10 µm barely distinguished in LM and ventral striae ca 65 in 10 µm, whereas as H. hyalina and A. vaughanii Giffen have clearly visible striae, 20 – 23 in 10 µm and 28 – 30 in 10 µm, respectively. Amphora hyalina, reported from Yap by Navarro & Lobban (2009, figs 97, 98), has an exposed, dorsally deflected raphe with a conopeum extending dorsally on the dorsal raphe ledge; the striae are finely biseriate, the areolae consistently small, apicallyelongated slits. Amphora vaughanii was recorded from Guam (Lobban et al. 2012, pl. 56, figs 7 – 9), it has biseriate striae of very fine pores on the dorsal surface and a line of very closely spaced slits on the mantle, conopea absent; its position in Halamphora or Amphora has not yet been considered.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFF0B04FF357CCBFCA0FD34.taxon	discussion	Lobban et al. (2012) reported A. complexa (Gregory) Cleve from Guam, but J. S. Park et al. (2018) noted that the valve size and stria density of the voucher specimens match Auricula densistriata K. Osada (Osada 1997). Stria density for A. complexa is 15 – 20 in 10 µm (Peragallo & Peragallo 1897 – 1908), but Lobban et al. reported 26 – 28 in 10 µm. In SEM (Figs 8, 9) we measured 27 striae. Auricula complexa species was correctly reported from Federated States of Micronesia — Yap by Navarro & Lobban (2009) and Chuuk by Park et al. (2022) — and may well be present in Guam but we have no evidence of it, so for now remove it from the flora.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFF0B04FF357E12FEA8FB13.taxon	description	Samples: GU 21 AM- 2, GU 21 AN- 1; GU 52 J- 3, GU 52 K- 4, GU 52 S- 2; GU 58 G- 4 D	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFF0B04FF357E12FEA8FB13.taxon	diagnosis	Diagnostics: Colonial, as in B. paxillifera, the “ slide rule ” diatom, but inflated in the middle. Uniseriate striae with external costae.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFF0B04FF357E12FEA8FB13.taxon	discussion	Comment: As noted by Lobban et al. (2012) for the nominate form, marine forms were orphaned when Jahn & Schmid (2007) redefined B. paxillifera as freshwater / brackish, naming several new species, but excluding three marine groups distinguished by Schmid (2007). Our assignment of this variety to Group B, based on the nominate form, has not been verified and remains in limbo until Jahn completes her analysis. The short cristae at the central area are characteristic but we have images of specimens without them and without costae; further progress awaits completion of work on this group.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFF0B02FF357839FEC0FE1F.taxon	description	Samples: GU 77 A- 2 Observations: Colonial (tube-dwelling) species forming wide, branched colonies with many narrow tubes bundled together, each narrow tube containing a single file of cells (Figs 15 – 17); plastids Hshaped (Fig. 18). Valves hyaline, 45 – 51 µm long, 6 µm wide, striae parallel except convergent near apices, 37 in 10 µm. Cells linear-lanceolate with broadly rounded ends (Fig. 19). In SEM, striae parallel except radiate near the apices, areolae quadrangular except a row of larger areolae along one side of the raphe (Figs 20, 21). Central raphe endings separated by 7.1 – 8.6 µm, curved slightly away from the side with the larger areolae.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFF0B02FF357839FEC0FE1F.taxon	discussion	Comments: These microscopic colonies are very much smaller than those in southern California but that is not unusual for Guam tube-dwelling diatoms (so far only Homoeocladia [Nitzschia] martiana C. Agardh colonies found at seaweed size; Lobban & Tsuda 1993). Our cells appear to differ from B. hyalina in larger size, wider separation of central raphe endings and shape of the apex, from B. fragilis in shape and longer central area, and from B. micans, which is longer but narrower with coarser striae and very long central area (Table 1). However, variability in some of these characters warrants caution. First, there are discrepancies between Chastain & Stewart’s (1985) California populations compared to type material, some of them noted by those authors, i. e., the stria density, the shape of the apex, and the extent of the axial row of enlarged areolae. The difference in stria density might be significant but Chastain and Stewart’s statement is broad and imprecise (“ approximately 32 – 38 ” in 10 µm), and Round & Brooks’ is even more vague (“ more than 40 ”). Lobban (1985) in a floristic survey including southern California, reported striae of B. hyalina to be “ ca. 45 in 10 µm … visible only in the electron microscope ” but no SEM was published. Perhaps a more significant difference lies in the hemilanceolate depression formed by the very long areolae in San Diego populations, which Chastain & Stewart noted as a “ signal feature, ” though saying that “ the row of enlarged pores … appears to be somewhat more prominent ” than in the type material. All species of Berkeleya in Table 1 are reported in the literature to have a row of enlarged areolae along one side of the raphe, so what is distinctive in the San Diego populations is the width and the depression. Round & Brooks (1973, figs 7, 8, 15) noted that the larger pores appeared to be in a “ slight depression; ” the pores are trapezoidal, wider toward the axis. Chastain & Stewart (1985, figs 6, 10) show a single row of larger areolae in their TEM (fig. 6) but in the SEM (fig. 10) most in the widest part are divided. We have seen such depressed zones in a few samples that we could not identify to species (Figs 24, 25) and even, rarely, in the present colony. In all these, the distance between central raphe endings was <7 µm but perhaps not significantly different from the majority of the colony (in the two specimens in Figs 24, 25 = 4.2 and 6.2 µm but in Guam specimens up to 6.7 µm). This brings into question whether the depressed area is a consistent enough character to use for taxonomy, and how much distance between central raphe is needed to separate species. Chastain & Stewart noted the great difference in latitude and water temperature between Togo (type locality) and San Diego, to which we might add, the different ocean basins. Second, there are the differences between our material and both of the other two populations which require additional material from Guam and re-examination of type material (or better, more samples from Togo as well!). At this point both the Guam and Togo populations can be considered inadequately studied. The biggest problem with the Togo material is the vague stria density given by Round & Brooks; we tried counting it from the published images (Round & Brooks 1973, figs 8, 15) and got answers very much higher than the> 40 given, but only magnifications are given for the images and perhaps the plates were reduced in publication without correction of the captions. Thus, we have identified our specimens only as “ cf. hyalina ” and shown their morphology for future reference.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF90B02FF357CDCFEA4FB47.taxon	description	Samples: GU 7 Y- 4 Dimensions: Length 42 – 63 µm, width 27 – 30 µm	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF90B02FF357CDCFEA4FB47.taxon	diagnosis	Diagnostics: Deeply sculpted valve in girdle view, central dome flanked by two smaller ones that abut or are themselves separated from the tall pseudocellus-bearing horns on the two poles. Many spines on the domes and the central dome with two rimoportulae with very long external tubes. The deep grooves (sulci) (Fig. 29) were used to distinguish Biddulphiella from Biddulphia (Sims et al. 2023).	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF90B02FF357CDCFEA4FB47.taxon	discussion	Comments: Differs from Biddulphia biddulphiana (J. E. Smith) Boyer (Navarro & Lobban 2009, figs 28 – 31) in the more elongate, rostrate valve outline and number of domes. VanLandingham (1968, p. 562) commented on which specific epithet had priority and listed the extensive synonymy under B. tridens.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF90B02FF3579E5FE7FF9D9.taxon	description	Samples: GU 52 O- 4 Dimensions: Length 38 – 54 µm, width ca. 6 µm; striae 9 – 10 in 10 µm	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF90B02FF3579E5FE7FF9D9.taxon	diagnosis	Diagnostics: Linear, symmetrical valve, similar in size and stria density to B. ridicula (see below), which is strongly asymmetrical.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF90B02FF3579E5FE7FF9D9.taxon	discussion	Comments: Biremis is characterized by alveolate striae. Several smaller species have been observed but not yet identified.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF90B01FF357B6EFD68FD4F.taxon	description	Samples: GU 52 O- 4 Dimensions: Length 46 – 74 µm, width of valve 9 µm, width of frustule in girdle view 24 µm; striae 7 in 10 µm	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF90B01FF357B6EFD68FD4F.taxon	diagnosis	Diagnostics: Amphora - like frustule, asymmetrical (Figs 32, 35). Valve asymmetrical (Figs 34, 36), lanceolate, with short, broad striae along each margin and the raphe strongly displaced to the “ ventral ” striae, leaving strongly asymmetrical axial area. Striae alveolate (Fig. 37).	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF90B01FF357B6EFD68FD4F.taxon	discussion	Comments: This species is similar in size and stria density to Biremis ambigua (see above), but that species is symmetrical. The relatively large frustules are shaped like Amphora arenaria Donkin, with which it co-occurred in this sample from calcareous sand, but the striae are very distinctive. Round et al. (1990) described the areolae in this genus as consisting of two incompletely separated chambers, closed internally by a cribrum, and opening externally by slit-like foramina, one at each end of the areola, resulting in two longitudinal lines that are the most evident feature in external SEM views. Witkowski et al. (2000) mention this species being reported only from South Africa and the North Sea (Europe), populations for which there is no SEM yet; a comparison needs to be made to confirm the identity of the Guam specimens.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFA0B01FF357F9DFB31F99E.taxon	description	Samples: GU 74 B- 4 Dimensions: Diam. 100 µm	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFA0B01FF357F9DFB31F99E.taxon	diagnosis	Diagnostics: Lines of large, paired oval pores running along lines from the margin to the central area.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFA0B01FF357F9DFB31F99E.taxon	discussion	Comments: Greville noted that the most similar species is C. diplostictus G. Norman ex Greville (Williams 1988, pl. 26, figs 5, 6), but that species is twice the diameter and has many interpolated short “ striae ” not present in our specimen. Despite some vague topography in the central space, compared to completely hyaline in Greville’s (1863) drawing, we are satisfied that we have C. robertsianus. The character of these pores (called punctae or granules by Peragallo & Peragallo 1897 – 1908) seems not to have been studied in SEM. Arrangement of pores distinguish C. robertsianus from species with scattered pores, such as Coronia daemeliana (Grunow) Ruck & Guiry, already transferred from Campylodiscus. Campylodiscus robertsianus is one of several taxa present in the Guam flora and lacking infundibula that most likely qualify for transfer to Coronia but were not studied by Ruck et al. (2016 a, b, Ruck & Guiry 2016), i. e., Campylodiscus decorus var. pinnatus (the species was transferred but not the variety), C. humilis and C. brightwellii in our flora. Park et al. (2018) already transferred the first of these to Coronia decora var. pinnata (Peragallo) Lobban & JoonS. Park, and we are tempted to propose here the transfer of C. robertsianus. However, Ruck & Guiry (2016) gave no unambiguous morphological diagnosis for Coronia, relying instead on sequence data. Nomenclaturally, while a variety must go with its parent species when the species is transferred, transferring C. robertsianus would require a decision that this species accords with the new genus, which is uncertain in the absence of molecular data. This species was described from Queensland, Australia and has been reported from Samoa. Greville (1863) delighted in it as “ one of the most exquisite species of this charming genus. ” We have only this single specimen from Guam and a fragment from Yap, both in LM.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFA0B00FF357BACFC74FEE6.taxon	description	Samples: GU 70 A- 2 A, GU 68 A- 2, inter alia Dimensions: Length 8 µm, width 5 µm; stria density 26 in 10 µm on both valves.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFA0B00FF357BACFC74FEE6.taxon	diagnosis	Diagnostics: Sternum valve with crista marginalis dividing the striae. Striae have single transapically elongate areola distal to crista and 2 – 3 areolae proximal.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFA0B00FF357BACFC74FEE6.taxon	discussion	Comments: Abundant in GU 70 A- 2 A. This species was recently described from Indian Ocean and Pacific Ocean sites, including the Marquesas I., French Polynesia.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFB0B00FF357C44FB29FCF6.taxon	description	Samples: GU 52 O- 4, inter alia Dimensions: Diam. 27 – 30 µm, stria density at margin 21 - 22 in 10 µm.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFB0B00FF357C44FB29FCF6.taxon	diagnosis	Diagnosis: Ring of short striae surrounding flat central zone with or without short spines.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFB0B00FF357C44FB29FCF6.taxon	discussion	Comments: The stria density given by Hustedt is ca. 18 in 10 µm. Hein et al. (2008, p. 18, pl. 2, fig. 2) reported C. hauckii var. mesoleia, which has a clear center, with 28 striae in 10 µm. It is not clear from Hustedt’s text about the nominate variety whether he thought the unregelmässig punktiertem Mittelfeld was perforated, because he also used punktiert in reference to the short striae. The variety may not be justified, given that the difference in the central zone of the nominate variety comprises only small papillae, and there is only a slight difference in stria densities between the forms (20 in the variety). Our stria density is higher, and Hein et al. ’ s still higher. Our SEM shows that this species lacks rimoportulae, so it does not belong in Coscinodiscus (see Round et al. 1990).	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFB0B0FFF357E53FEF3FB15.taxon	diagnosis	Diagnosis: Differing from Dictyoneis marginata in the broadly lanceolate outline, absence of field of small pseudoloculi around the central area, and smaller outer openings of the pseudoloculi, especially along the margin.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFB0B0FFF357E53FEF3FB15.taxon	materials_examined	Holotype: Specimen at 10.2 mm E and 6.0 mm S of the mark on slide 3056, deposited at Diatom Collection, Academy of Natural Sciences of Drexel University, Philadelphia, accession number GC 20106. Fig. 44.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFB0B0FFF357E53FEF3FB15.taxon	description	Type locality: Guam, Apra Harbor, Scuba Beach, 13 ° 27.840 ', 144 ° 39.360 ', scarce in biofilm on calcareous sand ca. 10 m deep, in communities with Arcuatasigma spp. (Lobban & Reid 2018), Progonoia spp. (Lobban 2015 b), and several species listed below. Sample GU 52 X- 5 b, 10 May 2015, coll. C. S. Lobban & M. Schefter	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFB0B0FFF357E53FEF3FB15.taxon	etymology	Etymology: Apapa, genitive noun in apposition, for the type locality in Apra Harbor, not far from Cabras Island. Ayong (2023) explains that, “ Apra is a corruption of the Chamorro word ‘ apapa ’ which means ‘ low. ’ Apapa is the original name for what is now known as Cabras Island. ”	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFB0B0FFF357E53FEF3FB15.taxon	description	Morphology: Valves broadly lanceolate (Figs 44 – 46), 94 – 115 µm long, 22 – 26 µm wide, outer pseudoloculi in rows giving apparent stria density, especially in LM, of 8 – 12 in 10 µm, (Figs 44, 45) but true striae measured on interior views 24 – 26 in 10 µm (Figs 52, 55). External raphe slits straight, bordered by thin ridges of silica (Fig. 48, arrow), terminal endings deflected in opposite directions. Inner layer of pores completely overlain by pseudoloculate framework forming larger pores, except in a variable zone near the sternum and at the apices where the outer openings are also small (Figs 48, 49 and cf. fracture wall, Fig. 54). The outermost areolae are very large and in LM give the impression of chambers (cf. Mastogloia) (Figs 44, 45) but are simply part of the outer layer (Figs 46, 47,49). There is also a long groove on each side in the outer layer near the apex (Figs 47, 50, 57). Figs 50 and 51 compare exterior features of the new species with a specimen of D. marginata (F. W. Lewis) Cleve from Georgia. Interior surface shows regular striae opening by transapical slits (Figs 52 – 55); many short striae and a few longer ones are interpolated on the mantle forming a denser fringe (32 striae in 10 µm), followed by a hyaline border (Fig. 53). Raphe bordered by thick ribs, central and terminal endings simple, the latter with a very small helictoglossa. Wall structure (Fig. 54) shows deep pseudoloculate outer network over the basal striate layer. Figs 55 and 56 compare the similar internal surfaces of the new species with D. marginata. Girdle bands (Figs 47, 57, 58): copulae open: valvocopula with deep notch at the closed end filled by ligula on 3 rd copula (Fig 57, arrow), with two rows of pores along advalvar edge, scattered pores / pits elsewhere; two other copulae with similar structure. Additional records: GUAM: GU 52 V- 1! (biofilm); YAP, FSM: Y-D 2 (seagrass leaves) Registration: http: // phycobank. org / 104437	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFFB0B0FFF357E53FEF3FB15.taxon	discussion	Comments: Dictyoneis apapae differs markedly from D. marginata [Hustedt 1931 – 1959, p. 576, fig. 1009; Montgomery 1978 pl. 81 C – F; Round et al. 1990 p. 468 (implicitly showing D. marginata); Hein et al. 2008, p. 51, pl. 26, fig 2, pl. 27 fig. 1] but there seem to be additional discrepancies among the images in the literature. The apical groove in Round et al. (1990) is long like that in D. apapae, and they also note that the external raphe slits are bordered by thin ridges of silica, which can be seen in our images of D. apapae but not in our D. marginata specimens (Figs 50 vs. 51). Moreover, Round et al. (1990, p. 469, fig. h) show thick transverse costae and note that “ the small poroids of the inner layer are difficult to distinguish because of the strong development of the ribs, ” a description that does not fit D. apapae (Fig. 54) or even our Georgia specimens (Fig. 56). These seem to be small discrepancies compared to the differences in the central area, marginal pore size and constriction (the latter two used by Cleve 1890 as taxonomic criteria); we are therefore confident that the Guam species cannot be included in D. marginata, but not so confident in our identification of the D. marginata specimen. When Cleve (1890) erected the genus, he provided a key to the known species, of which only two were lanceolate, and only one of those had marginal pores larger than the ones on the valve face, that was D. thrumii Cleve, described in the same article. However, he gave no drawings and the description, based on a single specimen from a sea cucumber gut in China, mentions little of the structure. His valve was larger than our specimens, 150 µm long, 32 µm wide. Montgomery (1978, pl. 81 A, B) showed an unnamed lanceolate species from Florida with broad semilanceolate zones of smaller pseudoloculi on each side of the raphe, clearly different from ours. There is need for further study of this genus, and the assertion by Round et al. (1990, p. 468) that, “ only the type [species] is recorded at all frequently ” should not be a license for assigning every constricted specimen to D. marginata.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF40B0FFF357832FB8CF882.taxon	description	Samples: GU 50 D, GU 52 U- 1 Dimensions: 35 – 40 µm long, 4 – 5 µm wide, 40 biseriate striae in 10 µm.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF40B0FFF357832FB8CF882.taxon	diagnosis	Diagnostics: Apex rounded; sternum lanceolate, narrow; ocellulimbus 6 – 8 pores wide.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF40B0FFF357832FB8CF882.taxon	discussion	Comments: This species is separated from H. prasadii by the dimensions according to the key in Sabir et al. (2018). Like that species, it has a lanceolate sternum, in contrast to other species in which the sternum is linear. The images published by Navarro & Lobban (2009) can be better identified as Sabir & Theriot’s new species, although the stria density is higher than their specimens. Hyalosynedra prasadii, or something like it, has also been noted in a few samples, but both species were scarce and detailed comparison with Red Sea and Florida species is not yet possible and, because of the fine discriminations needed, it is possible that these species are regional endemics and that our western Pacific species are different. We make this provisional record now only to point out that the record in Navarro & Lobbban (2009) is not H. laevigata. This genus needs more detailed study in our region but H. laevigata is present in our flora, see below.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF50B0EFF357DCEFB64FDAC.taxon	description	Samples: GU 44 Z- 15, GU 58 G- 4 A Dimensions: length 114 – 132 µm, width 5 – 6 µm.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF50B0EFF357DCEFB64FDAC.taxon	diagnosis	Diagnostics: Long, lanceolate, hyaline cells, apices rounded to weakly capitate; linear midrib visible in LM; pseudocellus with three rows of pores; rimoportulae asymmetrical.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF50B0EFF357DCEFB64FDAC.taxon	discussion	Comments: Differing from H. lanceolata Belando, Jiménez & Aboal, which has a broad, lanceolate sternum. It is so similar in size and shape to Stricosus cardinalii E. C. Theriot & Lobban (see below) that the two taxa can scarcely be distinguished in LM. In SEM, the character of the rimoportulae and the depth of the pseudocellus separate them. See also comments above on H. cf. al-turkii.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF50B0EFF357FB9FCF5FB82.taxon	description	Samples: GU 44 AR- 3 Dimensions: Length 135 – 143 µm, striae in 10 µm 9 – 10, increasing to 10 – 12 near apex.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF50B0EFF357FB9FCF5FB82.taxon	diagnosis	Diagnostics: The apically oriented areolae, the triangular profile of the valve, always lying in girdle view, and the broad valvocopula with deep septum, together with apically elongated areolae, make this species unique so far even in LM.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF50B0EFF357FB9FCF5FB82.taxon	discussion	Comments: Two specimens, including a complete frustule were found in LM. The apically elongated areolae are evident in both images; the three inflated areas are suggested by the focus and the short, intercalated striae (Fig. 63, black arrowheads), and the path of the midrib and septum are shown by arrow and arrowhead in Fig. 63. The septum is very unusual in this species (Lobban 2021, fig. 19). Previously known only from Majuro, Marshall Islands.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF50B0EFF3579A8FC30F944.taxon	description	Lobban et al. 2012, p. 281, pl. 35, figs 1, 2 (as “ M. pseudolatecostata ”) Lobban et al. 2012, p. 279, pl. 33, figs 7, 8 (as “ M. ovata ”) Samples: GU 44 T- 1, GU 44 AJ, GU 44 AU- 1; GU 52 P- 7; GU 70 A- 2 A Our specimen published as voucher for M. pseudolatecostata must be rejected because the stria density is too high (21 – 24 vs 12 – 14 in 10 µm). It is a better match for M. ovata than the voucher specimen cited in the same paper. SEM images of such specimens are shown in Figs 65, 66. A specimen from Bikar Atoll, Marshall Islands that matches M. pseudolatecostata is shown in Fig 67; this species not yet identified in Guam. The specimen claimed as a voucher for M. ovata in Lobban et al. 2012 less clearly matches the description in Hustedt (1931 – 1959) and close to Hein et al. (2008, pl. 40, fig. 3) “ Mastogloia cf. ovata. ”	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF50B0EFF3579A8FC30F944.taxon	discussion	Comments: The inner margin of M. ovata has indentations at each cross wall (Fig. 66), that of M. pseudolatecostata in the middle of each partectum (Fig. 67).	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF50B0DFF357BE2FDDEFB53.taxon	description	Samples: GU 52 X- 5 Dimensions: Length 30 – 35 µm, width 14 µm, striae radiate, 25 in 10 µm	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF50B0DFF357BE2FDDEFB53.taxon	diagnosis	Diagnostics: Broadly lanceolate, rostrate, depressed area not strongly differentiated but a longitudinal line visible in the middle of it (Figs 68, 69 arrows). Chambers quadrate to elongate with convex inner edges, not reaching apices. In SEM external view (Fig. 69) uniform areolae in the outer zone, transapically elongated areolae in the depressed zone, irregular rib between them; raphe thickened. Internally, outer zone with transapical costae, inner zone smooth. Areolae opening internally, by quadrate set of small pores; outer zone of striae with costate virgae, inner zone with areolae in irregular longitudinal line, sporadically two lines (Fig. 70 arrow). Partecta 3 in 10 µm, in middle portion only, apically elongated with convex inner margins and scattered pores on the abvalvar surface.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF50B0DFF357BE2FDDEFB53.taxon	discussion	Comments: Uncommon in this biofilm sample. Specimens were smaller than Cleve’s and at low end of range in Hustedt. Hustedt (1931 – 1959), Stephens & Gibson (1980) and Loir & Novarino (2013) all show much variation. Moreover, there are considerable discrepancies between the various descriptions, leading us to qualify our identification with “ cf. ” First, Hustedt (1931 – 1959: 558) said that although the forms he found (only near Seychelles) differed from Cleve’s (1893) description (specimens from Florida), e. g. in stria density, he decided not to separate them. Stephens & Gibson reported stria densities in line with type material in Cleve (1893) and Boyer (1927). Specimens in Pennesi et al. were from Suluwesi, Indonesia. The SEM studies by Stephens & Gibson (1980) and Pennesi et al. (2012) are not completely comparable because partecta found by the latter were all broken. The partecta are square to apically lengthened with convex inner margins. Stephens & Gibson showed them to have delicate silica plaques with perforations; partecta in our specimens seem longer than in these other reports and we saw pores but no plaques (Fig. 70). Stephens & Gibson did not observe the edge of the mantle, where we and Pennesi et al. saw biseriate striae. Internally, there is a single line of quadripunctate foramina under the depressed area shown in both Stephens & Gibson and Pennesi et al. but in our specimens, there was a much looser row, sometimes double. Stephens & Gibson (1980; Florida) considered whether their specimens might match M. arabica Hendey, or if that might be synonymous with M. pisciculus. Establishing boundaries in these disparate populations of rare taxa will require more work; for now, we present our SEM observations to define what we found here.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF60B0DFF3579F8FB7FF8D8.taxon	description	Samples: GU 52 O- 4, GU 44 AS- 4 Dimensions: Length 31 – 32 µm, width 13 µm; striae 15 in 10 µm, areolae 16 in 10 µm.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF60B0DFF3579F8FB7FF8D8.taxon	diagnosis	Diagnostics: Central and terminal raphe endings deflected in same direction, central endings in opposite directions (Fig. 73), distinguish the genus from Petroneis and Navicula. Species based on shape, dimensions, and stria density. Valve rostrate; striae radiate, some shorter ones in center.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF60B0DFF3579F8FB7FF8D8.taxon	discussion	Comments: Rare specimens match the description of M. hexagona, which is smaller and more finely striated than M. angulata (42 – 48 µm x 16 – 16.5 µm, striae 11 in 10 µm, areolae 12 in 10 µm). J. Park et al. (2012) noted a single areola at the Voigt faults (Fig. 72, arrows) and larger areolae adjacent to axial area, which are present in our specimen. Our SEM images are the first for this species and show the areolae to be c-shaped (Fig. 73). Moreneis hexagona is distinguished from several other species by shape and stria density. J. S. Park et al. (2018) reported M. cf. hexagona from Chuuk with some hesitation because of a size difference. Present in biofilm with another Moreneis sp. in GU 52 O- 4, but also found in a gathering of Halimeda in GU 44 AS- 4. The other species does not match any of the species in this newly erected genus but it may have been described under Navicula.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF70B0CFF357DCEFD49FBD2.taxon	description	Samples: GU 58 G- 4 A, GU 44 I- 1, GU 44 Z- 15 Dimensions: Length 18.5 µm, width 7.4 µm; striae 20 in 10 µm.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF70B0CFF357DCEFD49FBD2.taxon	diagnosis	Diagnostics: Weakly sigmoid in girdle view, keel eccentric except in long-rostrate apices, striation bold in LM because of external costae between the striae; central striae biseriate towards to keel, triseriate towards the margin (Fig. 78), becoming rings of pores with central row of pores and diminishing towards apex (Fig. 77). Eccentric keels of the two valves are on opposite sides of the frustule (nitzschioid, not hantzschioid) (Figs 77, 78). Keel canal is closed except for circular fenestrae (Fig. 77).	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF70B0CFF357DCEFD49FBD2.taxon	discussion	Comments: Guiry (2017) explains why lorenziana is illegitimate and provides the earlier synonym. The ultrastructure of our specimens clearly matches SEM images in Poulin et al. (1990). It is apparently a brackish / estuarine species, with wide temperature tolerance (from Gulf of St. Lawrence to Florida + Guam). Abundant in Vietnam and Indonesia (Witkowski, unpubl.). Lopez-Fuerte et al. (2010: p. 63, pl. 37, fig. 21) show var. subtilis Grunow from Mexico and list the nominate variety. Nitzschia incurva somewhat resembles N. gaoi Bing Liu, S. Blanco & B. Q. Huang (2019), but that has small conopeal canals and uniseriate striae. Lobban & Ashworth (2022 b) did not transfer N. gaoi or their own N. maiae Lobban, Ashworth, Calaor & E. C. Theriot to Homoeocladia because of maintaining a narrow definition of the morphology of Homoeocladia and noted some other species in the region with doubtful formation of a conopeal canal that also have T-shaped external costae (one shown in Lobban 2023 a, figs 4 F, G).	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF70B0CFF357978FBDFFA4A.taxon	description	Sample: GU 52 G-A Dimensions: Valve 9.3 µm long x 2.3 µm wide; striae 50 in 10 µm.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF70B0CFF357978FBDFFA4A.taxon	diagnosis	Diagnostics: This species differs from O. pilosella Riaux-Gobin in the shape of the buciniportula, which here is a single trumpet.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF70B0CFF357978FBDFFA4A.taxon	discussion	Comments: Olifantiella spp. are barely discernable in LM, and the details are at the limit even of the desktop SEM. These images were taken at U. Texas on a full-sized SEM.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF70B0CFF3578E0FB77F9BD.taxon	discussion	Comments: J. S. Park et al. (2022, p. 14) made the case for recognizing this taxon as Parlibellus biblos. Stauroneis retrostauron must be deleted from the species list for Guam for now.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF70B0BFF357B8AFAADFE30.taxon	description	Samples: GU 52 O- 4, GU 52 X- 5 (biofilm on calcareous sand) Dimensions: Length 11 – 12 µm, width 5 µm; striae 17 in 10 µm	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF70B0BFF357B8AFAADFE30.taxon	diagnosis	Diagnostics: rhomboidal valves with central elevation and two elevated apical pore fields; large flaps on the four most-apical spines.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF70B0BFF357B8AFAADFE30.taxon	discussion	Comments: Kaczmarska et al. (2017) compared their specimens to similar species and concluded that there was no match. Our specimens are very close to their fig. 13 A. In their nomenclatural note, Kaczmarska et al. claimed that the correct epithet is minus, since Dimeregramma is a neuter noun, and Li et al. (2020, p. 13) used this transferring the species to Plagiogramma (also neuter). However, minus is an adverb and the correct adjective here is minor, which has the same ending across all genders in the nominative singular (Stearn 1973), as used by Gregory (1857) in the basionym.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF00B0BFF357F16FA83FC1F.taxon	description	Here we just want to note that this species, described from Guam and Yap and differentiated from P. intermedium W. Smith, is also similar in shape to P. acus A. Mann (1925, p. 133, pl. 29, figs 4, 5), described from the Philippines as being very similar to P. intermedium. Stidolph (2002) pointed out that P. acus has the diagonal striae at ca 80 º to one another, contrasting with P. intermedium and P. simulacrum. Pleurosigma simulacrum and P. acus both lack the calcar slit at the apex, which is present in P. intermedium. Mann also noted that the striae of P. acus are much coarser than other straight species (14, vs 26 in 10 µm for P. simulacrum). Thus, there are at least four straight, narrow species of Pleurosigma, the fourth being P. patagonicum Ferrario & Sar (Sar et al. 2012) (Table 2). We have checked all images we attributed to P. simulacrum, now including specimens from Saipan, Chuuk and Palau (Lobban, unpublished), and confirmed that they were correctly identified.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF00B0BFF35792CFE7BF925.taxon	description	Samples: GU 44 Z- 15, GU 52 Q- 10 a, GU 62 A- 7, GU 66 G- 5, GU 68 F- 8 Dimensions: Length 32 – 48 μm, width 6 – 8 μm; striae 30 – 32 in 10 μm	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF00B0BFF35792CFE7BF925.taxon	discussion	Comments: Majewska et al. (2019, p. 625), working on Proschkinia spp. epizoic on sea turtles, described a new species P. torquata Bosak, Van de Vijver & Majewska, which they compared with P. complanatoides. They suggested that our Guam specimens might be a new species because they saw no widening of the central area (GU 44 Z- 15: Fig. 90) and the internal fistula was not like P. complanatoides. However, Kim et al. (2020) studied Grunow’s specimens of P. complanata with SEM and showed a fistula matching ours, also matching in the presence of a flap over the external fistula opening (Figs 87, 88) and a raised rib on the raphe internally for some distance from the central nodule (Fig. 90). One short stria on the side with the fistula (Fig. 88), and a silica flap over the fistula opening; central striae on opposite sometimes further apart (Figs 87, 88 vs. 90). Comparing our specimens to P. torquata, the fistula has a similar series of spheres, and the external opening is also covered by a flap, but P. torquata has longitudinal silica strips over the central part of the valve face and the apices are rounded rather than acute. Kim et al. (2020, table 4) listed Guam specimens with P. complanata not P. complanatoides and their images of authentic (including type) material convince us that there are no differences that would warrant a new species. We have seen this species across Micronesia, and it seems so far to be the only species present. We remove P. complanatoides from the Guam flora.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF20B09FF357DCEFDE3FD4E.taxon	description	Sample: GU 52 U- 1 Dimensions: 51 µm long (on the axis with the ocelli), 42 µm wide	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF20B09FF357DCEFDE3FD4E.taxon	diagnosis	Diagnostics: Quadrate, false pseudoloculate valve, having two elevations with ocelli and two unelevated points with rimoportulae.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF20B09FF357DCEFDE3FD4E.taxon	discussion	Comments: Differing from Pseudictyota dubia (Brightwell) P. A. Sims & D. M. Williams (Navarro & Lobban 2009, figs 21 – 24), which has six angles, three with ocelli and three with rimoportulae; and from P. reticulata (Roper) P. A. Sims & D. M. Williams (Lobban et al. 2012, pl. 3, figs 3, 4, as Triceratium dictyotum P. A. Sims & R. Ross), which is broadly lanceolate with two angles each with both an ocellus and a rimoportula.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF20B09FF357F9BFE17FA90.taxon	description	Sample: GU 26 A Dimensions: Length 5.5 – 9.2 µm, width 2.3 µm, striae 15 in 10 µm	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF20B09FF357F9BFE17FA90.taxon	diagnosis	Diagnostics: Small, clavate (heteropolar), with a clear pore field at one pole, simple, stick-like spines arising from areolae, whereas in S. rhombica there are “ accessory ” spines flanking the larger central spines (C. Li et al. 2018).	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF20B09FF357F9BFE17FA90.taxon	discussion	Comments: Many small Fragilariaceae have been studied recently, incorporating much debate on generic boundaries. Serratifera Ashworth, Chunlian Li & Witkowski (in C. Li et al. 2016) was established largely on molecular grounds and emended on morphological grounds by the same authors (in C. Li et al. 2018). Morales et al. (2019: 274) argued against the new genus and for inclusion of its species in the older genus Pseudostaurosira D. M. Williams & Round. Witkowski did not accept the argument (personal communication during ms. preparation), so we have presented this and the next species under their original names. Morales et al. transferred them to Pseudostaurosira andersonii (S. Sato, Chunlian Li & Witkowski) E. A. Morales, Novais & C. E. Wetzel, and P. rhombica (S. Sato, Chunlian Li & Witkowski) E. A. Morales, Novais & C. E. Wetzel, respectively. The senior author cannot contribute to this debate. All small Fragillariaceae are rare in our Guam samples to date, probably because the frustules are washing in from their primary habitats (mostly sediments and biofilms).	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF20B09FF3578B6FDF2F9B4.taxon	description	Sample: GU 52 P- 9 Dimensions: Length 8 µm, width 2.7 µm, striae 13 in 10 µm	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF20B09FF3578B6FDF2F9B4.taxon	diagnosis	Diagnostics: Small, rhomboidal (slightly heteropolar). Spines have accessory spines alongside, but these are not clear in our images.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF20B08FF357B91FB95FCE0.taxon	description	Samples: GU 44 U- 2, GU 44 Z- 15, GU 44 BV- 3, GU 52 P- 9, GU 52 Q- 1 a. Description of wild material: Plastids relatively large, numerous (Figs 98, 99), valves 113 – 193 µm long, 7 µm wide, 40 striae in 10 µm (Figs 100, 101), ocellulimbus 8 – 9 pores tall (Fig. 102), usually two spines (Fig. 102), rimoportula symmetrical, as for the genus (Fig. 103).	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF20B08FF357B91FB95FCE0.taxon	discussion	Comments: Although the record of this species was established in 2018, we wish to add these further observations. Stricosus harrisonii is the only linear species of Stricosus found so far in Guam. It was described as 88 – 152 µm long, relatively broad (5 – 9 µm), with a narrow, linear sternum, 38 – 41 biseriate striae in 10 µm, and with a single spine over the ocellulimbus (Sabir et al. 2018). In a variety of wild samples, however, there were two spines, as shown here. Also described from the same material was S. cardinalii, (Sabir et al. 2018, figs 99 – 103), which usually has two spines over the ocellulimbus. While S. harrisonii is essentially linear, the shape and size of S. cardinalii is very much like Hyalosynedra laevigata (see above). In SEM, S. cardinalii is distinguished by the symmetrical rimoportulae and deep ocellulimbi characteristic of Stricosus. Stricosus harrisonii and S. cardinallii from Guam are distinct from similar large species in Florida / Caribbean (S. navarroensis E. C. Theriot & Ashworth, S. blumbergii E. C. Theriot & Ashworth) and the Red Sea (S. alfageehii Sabir & E. C. Theriot, S. madanii Sabir & E. C. Theriot) (Sabir et al. 2018), possibly suggesting regional endemicity. Belando et al. (2018) identified the sequence labeled GU 44 AI as being H. laevigata but it is actually Stricosus harrisonii, which was published concurrently.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF30B08FF357E45FD32FAF0.taxon	description	Samples: GU 44 Z- 15, GU 52 P- 9 Dimensions: 12.8 – 19.8 diam., areolae 8 – 9 in 10 µm	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF30B08FF357E45FD32FAF0.taxon	diagnosis	Diagnostics: Areolae linear, not radial, single row of fultoportulae around the margin, their external part ending in a cuplike structure with a central post. Rimoportula inserted between two fultoportulae (rather than replacing one). Two central fultoportulae.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF30B08FF357E45FD32FAF0.taxon	discussion	Comments: Although the areolar density is lower than most records (Y. Li et al. 2013 the exception), these specimens seem to agree with the modern concept of the species originally described from the Philippines by Mann (1925). The surveys of Thalassiosira diversity in Argentina (Sar et al. 2002), Guangdong Province, China (Y. Li et al. 2013), and South Korea (J. S. Park et al. 2016) are all very helpful in identifying the species here.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF30B08FF357856FEFFF8A2.taxon	description	Samples: GU 52 X- 5 Dimensions: Length 121 – 158 µm, width 22 µm; striae 12 – 14 in 10 µm, fibulae 7 in 10 µm.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF30B08FF357856FEFFF8A2.taxon	diagnosis	Diagnostics: Large panduriform species with prominent external costae running the width of the cell.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFF30B08FF357856FEFFF8A2.taxon	discussion	Comments: Similar to T. plana (W. Smith) Pelletan [Peragallo & Peragallo 1897 – 1908 p. 270, pl. 70, fig. 18; Sims 1996, pl. 194, fig 2; Lopez-Fuerte et al. 2010, pl. 38, fig. 1 (all as Nitzschia plana W. Smith)], but that has 19 – 20 striae in 10 µm. Not clear from literature that either species has external costae. Montgomery (1978) has two images (pl. 160 C and 161 D) labeled as “ Nitzschia jelinecki ” but neither has external costae. Peragallo & Peragallo (1897 – 1908) commented that they had only seen it in “ exotic ” samples, the one figured from Java; type was from the Nicobar Islands. This species needs much more study before we can say whether the Guam specimens belong in it or elsewhere.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFEC0B17FF357C38FAB0FC54.taxon	description	Dimensions: Length 25 – 28 µm, width 17 – 20 µm; striae 9 in 10 µm (RV), 7 – 8 in 10 µm (SV) Samples: GU 52 X- 5, GU 52 N- 7, GU 52 P- 3 Diagnostics: The raised apices of the RV are diagnostic of the genus in LM, the large circular central area diagnostic of the species in contrast to V. florifera Riaux-Gobin, O. E. Romero, Compère & A. Y. Al-Handel (2011), which has a broad fascia. Comments: These specimens are in the lower end of the size range compared to most literature (see van de Vijver et al. 2009, table 1). There are two troubling differences between our specimens and those shown in the recent literature. First, comparison of the internal SV in our Fig. 112 with figs 16, 19 in van de Vijver et al. (2009) and similar images in Witkowski et al. (2000) and Riaux-Gobin et al. (2011) shows absence in our specimen of the elliptical opening and slit in the marginal ridges; this may be significant even though it was also absent in some specimens by van de Vijver et al. (2009, fig. 20). Secondly, Van de Vijver et al. (2009: 271, fig. 27, arrow) show small costae extending from the RV margin into the first row of areolae, a feature clearly absent from the external RV shown in Fig. 113. This is yet another genus with strong potential for additional species to be found.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFE60B1DFF357C4DFEA8FDF4.taxon	discussion	Reported by Lobban et al. (2012), still a valid species but in view of discussion in J. S. Park et al. (2022), we reconsidered the specimens. While the size and stria density are in the range of A. tenuissimus, the central area and instinct interfascicular rows are characteristic of A. subtilis (Gregory) Ralfs, to which we now refer all our Guam specimens (see also Lobban & Tharngan in prep.).	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFE60B1DFF357F51FAE1FD1A.taxon	discussion	Reported by Lobban et al. (2012), still a valid species but Lobban et al. (2022) showed that it differs from the species in our flora and renamed our species Ardissoneopsis fulgicans Lobban & Ashworth.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFE60B1DFF357E30FE7AFC5B.taxon	discussion	Reported by Lobban et al. (2012), Lobarzewsky’s diatom proved to be a valid but dubious species and not what we have here, so Lobban et al. (2022) renamed our species Ardissoneopsis appressata Lobban & Ashworth.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFE60B1DFF357EF0FB0BFBD8.taxon	discussion	Still a valid species but not what we have here; see Auricula densistriata above.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFE60B1DFF35796EFCE7FB7F.taxon	discussion	Reported by Navarro & Lobban (2009). Still a valid species but Lobban et al. (2022) show that the curved Climacosphenia in Guam is C. scimiter A. Mann.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFE60B1DFF3579CCFC9BFA9E.taxon	discussion	Possibly still a valid species but Lobban et al. (2020) recognized our material as Navicula tsukamotoi (Sterrenburg et al.) Yuhang Li et Kuidong Xu	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFE60B1DFF3578ABFED8F99A.taxon	discussion	Reconsideration of the literature to identify specimens in Yap lead to a better identification of specimens reported in Lobban et al. (2012) as L. clavata Gregory (Lobban & Tharngan in prep.), based on Hustedt’s (1961 – 1966) key, differentiating groups on the basis of rostrate ends, including clavata, from those with rounded apices, including hennedyi. Stria densities are similar in these two species.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFE60B1DFF357BB0FC1EF8B0.taxon	discussion	This species was reported from Guam by Lobban & Navarro (2009) (figs. 40 – 43) but based on recent work by C. Li et al. (2018), the specimens illustrated are not this species or genus and cannot be identified to any of the other genera described there. These specimens must await further study. We do not have any other specimens so far that can be identified as N. shiloi, although we anticipate it is present in the flora. The images remain posted in ProtistCentral under the name GU 7 B-UnID (http: // www. protistcentral. org / Taxa / get / taxa _ id / 586261).	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFE70B1CFF357C38FB2CFE90.taxon	discussion	Still a valid species but not what we have here; see Proschkinia complanata above.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFE70B1CFF357CB5FBF2FE15.taxon	discussion	Still a valid species but not what we have here; see Parlibellus biblos above.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFE70B1CFF357F32FB1EFD56.taxon	discussion	Reported by Lobban et al. (2012). Lobban et al. (2022) renamed that species Grunowago bacillaris (Grunow) Lobban & Ashworth but were unable to establish its presence in Guam, so established a new species, Grunowago pacifica Lobban & Ashworth, for the Guam material.	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
03C287AAFFE30B27FF357A0AFD82FE7D.taxon	discussion	Our species identified as Achnanthes citronella is a species of Schizostauron but we can so far only propose it as Schizostauron cf. trachyderma (F. Meister) Górecka & Riaux-Gobin. The difficulties in deciding whether it is that species, S. kajotkei Dabek, Górecka & Witkowski, or neither was discussed with reference to Chuuk specimens by J. S. Park et al. (2022), and the SEM images we have to date for this species do not resolve the question. See Riaux-Gobin et al. (2015), Davidovich et al. (2017) and Górecka et al. (2021).	en	Lobban, Christopher S., Witkowski, Andrzej (2023): Marine benthic diatoms of Guam: new records, Dictyoneis apapae sp. nov., and updates to the checklist. Micronesica 2023 (2): 1-75, DOI: 10.5281/zenodo.12118784
