taxonID	type	description	language	source
038987EE2151FFE4FD9A6929FE5849EA.taxon	type_taxon	Type species Ophiacantha laevipellis Lyman, 1883.	en	Stöhr, Sabine (2025): Two new species of brittle stars (Echinodermata: Ophiuroidea), living epizoic on a stalked crinoid. European Journal of Taxonomy 1022: 176-201, DOI: 10.5852/ejt.2025.1022.3087, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/3087/13763
038987EE2151FFE4FD9A6929FE5849EA.taxon	materials_examined	Material examined ANTARCTICA – Maria Island • 1 spec., syntype of Ophioripa conferta; depth 1300 fathoms (2379 m); 13 Dec. 1912; Australasian Antarctic Expedition; MNHN, MNHN-IE- 2013 - 10230 (formerly Ec Os 20388). CHILE – Gulf of Ancud • 3 specs, syntypes of Ophiomitrella chilensis; Paso Tenaún, S of Punta Tenaún; 42 ° 20 ′ 50 ″ S, 73 ° 22 ′ 00 ″ W; depth 70 m; 24 Jan. 1949; Lund University Chile Expedition stn M 42; triangular dredge; hard bottom; SMNH, SMNH-Type- 2321. INDONESIA – Kei Island • 1 spec., syntype of Ophiacantha tenuis; 5 ° 48.2 ′ S, 132 ° 13 ′ W; depth 304 m; 1899 – 1900; Siboga Expedition stn 253; MNHN Ec Os 2040. NORWAY • 3 specs, syntypes of Ophiactis clavigera; depth 364 – 546 m; 22 Oct. 1864; Uggla Expedition; on Gorgonia; SMNH, SMNH-Type- 3724. SOUTH ATLANTIC OCEAN – Gough Island • 1 spec., syntype of Ophiomitrella ingrata; depth 100 fathoms (183 m); 23 Apr. 1904; Scotia Expedition; MNHN, MNHN-IE- 2013 - 10308 (formerly Ec Os 20364). WEST INDIES – off St. Vincent • 1 spec., paratype of Ophiacantha laevipellis; depth 88 fathoms (160 m); 21 Feb 1879; Blake stn 232; MNHN, MNHN-IE- 2013 - 10160 (formerly Ec Os 20398).	en	Stöhr, Sabine (2025): Two new species of brittle stars (Echinodermata: Ophiuroidea), living epizoic on a stalked crinoid. European Journal of Taxonomy 1022: 176-201, DOI: 10.5852/ejt.2025.1022.3087, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/3087/13763
038987EE2151FFE4FD9A6929FE5849EA.taxon	discussion	Remarks When Verrill (1899 a) erected Ophiomitrella, he described it in a confusing dichotomous list, from which it is difficult to extract the characters that delimit this genus. Under section “ A ”, he sorted species in which the adoral shields are restricted to the proximal part of the oral shield, but under “ A. A. ” they extend around the oral shield. Ophiomitrella is found under “ B. B. ”, which doesn’t mention adoral shields, but has uncovered radial shields, whereas “ B. ” is meant for species with covered radial shields. Finally, under “ n. n. ”, Ophiomitrella has separated dorsal arm plates and thorny, slender arm spines that meet dorsally. The only species assigned to Ophiomitrella was O. laevipellis, making it the type species of the genus by monotypy. According to the redescription (Verrill 1899 b), Ophiomitrella should have small, widely separated radial shields, not bearing granules or spines, adoral shields limited to the proximal part of the oral shield, disc with scattered granules or stumps. In the same work (Verrill 1899 b), O. laevipellis is described as having long, narrow, covered radial shields, with only their distal part exposed, which was here confirmed by examination of publicly available photos of the holotype (MCZ: IZ: OPH- 1957) and photos of a paratype taken by the author (Fig. 1 I – J). Verrill subdivided Ophiomitrella, based on differences in arm spines, and placed O. laevipellis in one subgroup, whereas Ophiomitrella cordifera (Koehler, 1896) and Ophiomitrella globulifera (Koehler, 1896) formed the other subgroup. The latter two species match the description of the genus Ophiomitrella, which is however still a polyphyletic genus (O’Hara et al. 2018), despite the recent transfer of a group of species to the morphologically highly similar genus Ophiosemnotes (O’Hara & Thuy 2022). The necessary revision of these genera is far beyond the scope of this study, and as O’Hara & Thuy (2022) found, morphological characters that support the molecular clades have not been identified yet. In Table 2, the species were grouped by the nature of their disc spines (granules are considered homologous to spines). The majority of the species have more or less spherical (granule-like) disc spines, and the removal of Ophiosemnotes brevispina (H. L. Clark, 1911), that lacks disc spines, and Ophiosemnotes diaphora (H. L. Clark, 1911), that has granules, from the Ophiosemnotes group concurs with the latest published molecular phylogeny (Christodoulou et al. 2019). Thus, a revision of Ophiosemnotes appears necessary. However, on that tree, these two species are also in a separate clade from the remaining Ophiomitrella, and other members of this group are found in several clades on the molecular phylogeny (Christodoulou et al. 2019), which suggests that the granular disc spine group may be polyphyletic. Several of the species with stellate disc spines form a clade on the molecular tree, but the clade includes also Ophiomitrella barbara Koehler, 1904, which was here grouped as having elongated stumps, a character that is found in most of the species of Ophiosemnotes and in Ophiomitrella chilensis Mortensen, 1952 (see Fig. 2 E), which has not been sequenced yet. Other characters, such as the shape of the adoral (trapezoid / crescent) and oral shields (rhombic, larger / smaller than adoral shields) and the size of the radial shields, vary between species without forming obvious groups. Thus, disc spines are the most promising phylogenetically informative character, but need to be differentiated in more detail, and additional characters need to be identified. The issue is further complicated by the high similarity between Ophiomitrella and additional genera, which should also be re-assessed. Ophiomitra Lyman, 1869 shares with some Ophiomitrella not only the large adoral and small oral shield, but also the short, rounded radial shields. It was placed in Ophiotomidae Paterson, 1985 by O’Hara et al. (2018), but recent unpublished data (O’Hara pers. com.) suggest that its type species Ophiomitra valida Lyman, 1869 belongs in Ophiacanthidae instead. Ophiomitra leucorhabdota (H. L. Clark, 1911) falls into the Ophiotomidae clade, but several other species of Ophiomitra group with Ophiosemnotes (Christodoulou et al. 2019), which illustrates the genetic and morphological similarity between these genera. Last, but not least, the recently re-validated genus Ophiophthalmus Matsumoto, 1917 (Nethupul et al. 2022) is also rather similar to Ophiomitrella, having short rounded radial shields, small disc granules, and large crescent-shaped adoral shields proximal to the rhombic oral shield.	en	Stöhr, Sabine (2025): Two new species of brittle stars (Echinodermata: Ophiuroidea), living epizoic on a stalked crinoid. European Journal of Taxonomy 1022: 176-201, DOI: 10.5852/ejt.2025.1022.3087, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/3087/13763
038987EE215CFFE1FDB76A99FD604D18.taxon	description	urn: lsid: zoobank. org: act: BE 331259 - 774 D- 4810 - A 3 AE-E 81 A 4234 B 406 Fig. 2	en	Stöhr, Sabine (2025): Two new species of brittle stars (Echinodermata: Ophiuroidea), living epizoic on a stalked crinoid. European Journal of Taxonomy 1022: 176-201, DOI: 10.5852/ejt.2025.1022.3087, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/3087/13763
038987EE215CFFE1FDB76A99FD604D18.taxon	diagnosis	Diagnosis The dorsal disc is densely covered by low round granules, except on the radial shields, which are ¼ as long as the disc diameter. There are three spiniform lateral oral papillae. The adoral shields are trapezoid, larger than the oral shield, positioned only proximal to the oral shield. There are up to eight arm spines that do not meet dorsally.	en	Stöhr, Sabine (2025): Two new species of brittle stars (Echinodermata: Ophiuroidea), living epizoic on a stalked crinoid. European Journal of Taxonomy 1022: 176-201, DOI: 10.5852/ejt.2025.1022.3087, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/3087/13763
038987EE215CFFE1FDB76A99FD604D18.taxon	etymology	Etymology The specific epithet honours palaeontologist Ben Thuy whose work has greatly advanced the understanding of ophiuroid evolution.	en	Stöhr, Sabine (2025): Two new species of brittle stars (Echinodermata: Ophiuroidea), living epizoic on a stalked crinoid. European Journal of Taxonomy 1022: 176-201, DOI: 10.5852/ejt.2025.1022.3087, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/3087/13763
038987EE215CFFE1FDB76A99FD604D18.taxon	materials_examined	Type material Holotype TONGA – N Ha’apai group • 19 ° 03.7 ′ S, 174 ° 18.98 ′ E; depth 523 – 806 m; 14 Jun. 2000; Anders Warén leg.; Bordau stn DW 1595; Warén dredge; on Neogymnocrinus richeri (SMNH- 225978); MNHN, MNHN-IE- 2023 - 165. Paratype TONGA – N Ha’apai group • 1 spec.; same collection data as for holotype; SMNH, SMNH-Type- 10004.	en	Stöhr, Sabine (2025): Two new species of brittle stars (Echinodermata: Ophiuroidea), living epizoic on a stalked crinoid. European Journal of Taxonomy 1022: 176-201, DOI: 10.5852/ejt.2025.1022.3087, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/3087/13763
038987EE215CFFE1FDB76A99FD604D18.taxon	description	Description Holotype DORSAL DISC. Rounded pentagonal, 4.4 mm dd, dorsal scales obscured by spherical granules of variable size. Radial shields bell-shaped, about ¼ as long as dd, not bearing granules, pairs of radial shields separated by single column of narrow scales bearing few granules. VENTRAL DISC. Covered by overlapping round scales, few scattered granules similar to dorsal ones. Three lateral oral papillae, two proximal ones spiniform pointed, distalmost one shorter, compressed, blunt, all roughly thorny. In mouth angle, an unidentified compartment plate (see Hendler 2018). Lyman’s ossicle likely absent. Ventralmost tooth larger than papillae, flattened, pointed, roughly thorny. Upper teeth larger still, with increasingly rounded tip. Adoral shields limited to proximal edges of oral shield, trapezoid, with straight edges, proximal edge longer than distal edge, sides slanting. Oral shield rounded rhombic, about twice as wide as long, with small median process in distal edge, smaller than adoral shield. Madreporic shield longer, with central depression. ARMS. Dorsal arm plates fan-shaped, with convex distal edge, separated. Lateral arm plates arch around arm, meeting dorsally and ventrally. Up to eight conical, pointed, all over thorny, hollow arm spines, second dorsal spine longest, up to two arm segments long, ventral spines shorter than one arm segment. Spines do not meet across dorsal arm. Spine articular structures bordered by wavy ridge with unperforated stereom. First ventral arm plate narrow, extending into mouth slit, with median furrow. Other ventral arm plates rounded pentagonal, with strongly convex distal edge, acute proximal angle, slightly overlapping, distally a band of unperforated stereom. Single oval tentacle scale, closing tentacle pore completely. COLOURATION. Dark green, similar to host N. richeri, faded in alcohol. Paratype Disc rounded pentagonal, 4.4 mm dd, fewer disc granules than holotype, interradially three columns of round scales, central column overlaps outer two. Other characters as in holotype.	en	Stöhr, Sabine (2025): Two new species of brittle stars (Echinodermata: Ophiuroidea), living epizoic on a stalked crinoid. European Journal of Taxonomy 1022: 176-201, DOI: 10.5852/ejt.2025.1022.3087, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/3087/13763
038987EE215CFFE1FDB76A99FD604D18.taxon	discussion	Remarks “ Ophiomitrella ” thuyi sp. nov. falls within the group of species with low round disc granules. It is closest to O. tenuis in its granule covered disc and same number of arm spines, but the granules in O. tenuis are smaller, slightly taller, less spherical, and somewhat thorny, and the arm spines form a continuous row across the dorsal arm. Its radial shields are smaller (1 / 6 of dd), the adoral shields are crescent-shaped, narrower, smaller than its oral shield, the madreporite is larger and has a domed centre. “ Ophiomitrella ” thuyi resembles O. diaphora (H. L. Clark, 1911) in the size of the radial shields, the large adoral shields and disc granules of variable size, but that species is considerably larger, the radial shields are widely separated, the dorsal arm plates are rhombic, it has up to seven arm spines and four lateral oral papillae, the distalmost one enlarged. Among other species with similar radial shields and large adoral shields, O. mensa O’Hara & Stöhr, 2006 has stump-like disc granules with widened head, in O. globulifera (Koehler, 1896) the radial shields are widely separated by large scales and it reaches a larger size. All other species with round disc granules have smaller radial shields and / or crescent-shaped adoral shields (Table 2). There is some similarity to the specimens identified as O. conferta by O’Hara & Stöhr (2006), but they differ from the true O. conferta (Koehler, 1922) (Fig. 1 G – H) and from O. thuy in having large globular disc granules with short peduncle. Last but not least, none of the other species in Ophiomitrella and Ophiosemnotes are known to live on N. richeri, and the two new species described here may be the first records of epizoic ophiuroids on N. richeri.	en	Stöhr, Sabine (2025): Two new species of brittle stars (Echinodermata: Ophiuroidea), living epizoic on a stalked crinoid. European Journal of Taxonomy 1022: 176-201, DOI: 10.5852/ejt.2025.1022.3087, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/3087/13763
038987EE2159FFE1FDBB6E8BFD384FD4.taxon	description	urn: lsid: zoobank. org: act: 2691 A 6 FF-A 748 - 442 D-BBEA-CAF 345 D 2 C 153	en	Stöhr, Sabine (2025): Two new species of brittle stars (Echinodermata: Ophiuroidea), living epizoic on a stalked crinoid. European Journal of Taxonomy 1022: 176-201, DOI: 10.5852/ejt.2025.1022.3087, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/3087/13763
038987EE2159FFE1FDBB6E8BFD384FD4.taxon	type_taxon	Type species Warenophis andersi sp. nov., here designated.	en	Stöhr, Sabine (2025): Two new species of brittle stars (Echinodermata: Ophiuroidea), living epizoic on a stalked crinoid. European Journal of Taxonomy 1022: 176-201, DOI: 10.5852/ejt.2025.1022.3087, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/3087/13763
038987EE2159FFE1FDBB6E8BFD384FD4.taxon	diagnosis	Diagnosis As for type species.	en	Stöhr, Sabine (2025): Two new species of brittle stars (Echinodermata: Ophiuroidea), living epizoic on a stalked crinoid. European Journal of Taxonomy 1022: 176-201, DOI: 10.5852/ejt.2025.1022.3087, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/3087/13763
038987EE2159FFE1FDBB6E8BFD384FD4.taxon	etymology	Etymology The name is a compound noun of masculine gender, honouring the eminent mollusc expert Anders Warén, who collected the species and is a mentor and long-time friend of the author, and ‘ ophis ’ (meaning ‘ snake’ in Greek), alluding to Ophiuroidea.	en	Stöhr, Sabine (2025): Two new species of brittle stars (Echinodermata: Ophiuroidea), living epizoic on a stalked crinoid. European Journal of Taxonomy 1022: 176-201, DOI: 10.5852/ejt.2025.1022.3087, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/3087/13763
038987EE2159FFFDFDA46C94FBCA4BB1.taxon	description	urn: lsid: zoobank. org: act: D 822 AACB-B 0 DC- 41 F 6 - B 53 D- 35454 C 9 FE 02 B Figs 3 – 4	en	Stöhr, Sabine (2025): Two new species of brittle stars (Echinodermata: Ophiuroidea), living epizoic on a stalked crinoid. European Journal of Taxonomy 1022: 176-201, DOI: 10.5852/ejt.2025.1022.3087, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/3087/13763
038987EE2159FFFDFDA46C94FBCA4BB1.taxon	diagnosis	Diagnosis The disc is round, slightly domed, dorsally covered by large, irregular scales, with triangular, contiguous radial shields, that are ⅓ as long as the disc diameter. Granules and spines are completely absent from the disc. The dorsal arm plates are fan-shaped and contiguous. The ventral disc is covered by smaller round scales. At the apex of the jaw there are two elongated tooth papillae, along each jaw edge sit three small, round lateral oral papillae. The second tentacle pore is superficial outside the mouth slit. The up to four arm spines are flattened, wide, triangular, serrated, the dorsalmost spine is the largest. There is a single small, oval tentacle scale. The spine articulations on the lateral arm plate have a tongue-like dorsal extension.	en	Stöhr, Sabine (2025): Two new species of brittle stars (Echinodermata: Ophiuroidea), living epizoic on a stalked crinoid. European Journal of Taxonomy 1022: 176-201, DOI: 10.5852/ejt.2025.1022.3087, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/3087/13763
038987EE2159FFFDFDA46C94FBCA4BB1.taxon	etymology	Etymology The specific epithet honours Anders Warén, who collected the species and is a mentor and long-time friend of the author.	en	Stöhr, Sabine (2025): Two new species of brittle stars (Echinodermata: Ophiuroidea), living epizoic on a stalked crinoid. European Journal of Taxonomy 1022: 176-201, DOI: 10.5852/ejt.2025.1022.3087, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/3087/13763
038987EE2159FFFDFDA46C94FBCA4BB1.taxon	materials_examined	Type material Holotype TONGA – N Ha’apai group • 19 ° 03.7 ′ S, 174 ° 18.98 ′ E; depth 523 – 806 m; 14 Jun. 2000; Anders Warén leg.; Bordau stn DW 1595; Warén dredge; on Neogymnocrinus richeri (SMNH- 225978); on SEM stub; MNHN, MNHN-IE- 2023 - 164. Paratypes TONGA – N Ha’apai group • 2 specs; same collection data as for holotype; in ethanol, arm ossicles on SEM stub; SMNH, SMNH-Type- 10005.	en	Stöhr, Sabine (2025): Two new species of brittle stars (Echinodermata: Ophiuroidea), living epizoic on a stalked crinoid. European Journal of Taxonomy 1022: 176-201, DOI: 10.5852/ejt.2025.1022.3087, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/3087/13763
038987EE2159FFFDFDA46C94FBCA4BB1.taxon	description	Description Holotype DORSAL DISC. 4.8 mm dd, pentamerous. Round, domed disc, centre with irregular scales of variable size, no granules or spines. Radial shields scalene triangular, about as long as ⅓ of dd, completely contiguous. Primary rosette not distinguishable. Large rectangular interradial scale separates pairs of radial shields. VENTRAL DISC. Covered by scales smaller than on dorsal disc. Oral shield rhombic, 1.5 times as wide as long, distal edge convex, madreporite larger, no hydropore visible. Adoral shields crescent-shaped, proximal edge slightly concave, restricted to proximal edges of oral shield. Short jaws with two fingerlike tooth papillae, teeth wide, rounded. Three minute, round granule-like lateral oral papillae. Large superficial second tentacle pore outside mouth slit, with oval, scale-like adoral shield spine at edge of adoral shield. ARMS. Dorsal arm plates fan-shaped, as long as wide, contiguous. Lateral arm plates forming part of dorsal arm. Up to four arm spines, two dorsal spines largest, flat, triangular, proximal edge convex, distal edge straight, perpendicular to arm, imbricated, roof-like horizontal. Spines smaller on distal arm, but same flat shape throughout arm. Two ventral spines shorter, narrower, flattened. All arm spines with serrated edges. Ventral arm plates widely axe-shaped, twice as wide as long, lateral edges deeply excavated, distal edge straight, proximal edge wide flat angle, barely contiguous. Single round tentacle scale, not completely closing pore. COLOURATION. Dark green, similar to host N. richeri, faded in alcohol. Ossicles LATERAL ARM PLATES. Outer side with three to four spine articular structures on elevated part, shaped as two lobes, almost vertical in position, dorsal lobe tongue-shaped widened, ventral lobe short, muscle opening larger than nerve opening. Proximal outer edge of LAP with median process (spur). Stereom finely porous, along proximal edge a finer meshed band. Vertebral articular structures on inner side as angled flat ridge with finer pores than surrounding stereom, and round low knob on ventro-proximal part. Large pores distal to ridge, flat spur median on distal part. ARM SPINES. Articular structures as oval, flat, smooth knob with median slit and deep groove dorsodistal to knob. On largest spine, articular structures offset to distal part of lateral edge. VERTEBRAE. Zygospondylous articulation with zygosphene as long as zygocondyles, extending beyond lower ends of zygocondyles. No dorsal keel-like structure. Paratypes Specimen A: 4.1 mm dd, disc damaged, but plates and scales similar to holotype. Two arms completely broken off, three at distance from disc. Arms and ventral disc like holotype. Tentacle scale smaller than in holotype. Arm pieces present in sample. Specimen B: juvenile of 2.2 mm dd, dorsal disc with pentagonal central primary plate, slightly smaller, rounded square radial primary plates, small pentagonal proximal interradial plate, larger rectangular distal interradial plate. Radial shields scalene triangular, contiguous. Oral papillae as in other paratype and holotype. Large tentacle pores with single minute scale. Small arm pieces in sample, all but one arm broken off close to disc.	en	Stöhr, Sabine (2025): Two new species of brittle stars (Echinodermata: Ophiuroidea), living epizoic on a stalked crinoid. European Journal of Taxonomy 1022: 176-201, DOI: 10.5852/ejt.2025.1022.3087, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/3087/13763
038987EE2159FFFDFDA46C94FBCA4BB1.taxon	discussion	Remarks The taxonomic affinities of Warenophis andersi gen. et sp. nov. can be narrowed down to two families, Ophiacanthidae and Ophiotomidae. These are closely related and share numerous characters. All known ophiotomid genera have disc spines or granules, but the ophiacanthid genus Ophiohamus O’Hara & Stöhr, 2006 completely lacks disc armament, thus resembling the new species (O’Hara & Stöhr 2006). The flat, serrated arm spines of W. andersi are similar to those of Ophiotomidae, particularly Ophiocopa Lyman, 1883 and Ophiopristis Verrill, 1899. The analysis of the lateral arm plates showed that both families have a tendency to a tongue-like extension of the dorsal lobe of the spine articular structures (Fig. 4 E, G, I, K), particularly obvious in Ophiolimna (Fig. 4 G). The sigmoidal fold that is typical for the order Ophiacanthida is weakly expressed in the new species. The LAP of W. andersi has a proximal spur, which is more similar to Ophiotomidae than to Ophiacanthidae. Ophiotomidae LAPs have less conspicuous striations than those of Ophiacanthidae or they are limited to a small area, the new species lacks striations. The wavy border along the row of spine articulations on the LAPs is missing in W. andersi, but a slight elevation is present. The vertebral articular structure on the inner surface of the LAPs has the shape of a digit one (Numberger-Thuy & Thuy 2020) or an upside down check mark in Ophiacanthidae (Fig. 4 F, H), but has an elongated dorsal extension in some Ophiotomidae, e. g., in Ophiomitra leucorhabdota (Fig. 4 I), and in the new species it is a diagonal ridge, similar to Ophiocopa spatula (Fig. 4 C, L). This ridge could be homologous to the long part of the digit one or a shortened version of the ophiotomid ridge, with the short downwards pointing proximal part missing. The articular structures on the arm spines are similar between the new species and Ophiacantha and Ophiocopa (Fig. 4 M – P), perhaps slightly more similar to Ophiocopa. The evidence gathered from the new species is inconclusive, but Ophiacanthida is the most likely order. Ophiacanthidae is polyphyletic, and Ophiotomidae may need to be revised due to its type species appearing to be an ophiacanthid (O’Hara, unpubl. data). Family placement is proposed as incertae sedis until more data are available and the taxonomic issues with these families have been resolved. The Bayesian phylogenetic inference places W. andersi gen. et sp. nov. on the same major branch as Ophiacanthida, but not close to Ophiacanthina O’Hara, Hugall, Thuy, Stöhr & Martynov, 2017 (Fig. 5). The tree is more comb-shaped within the clade that holds the Ophiacanthina and its allies, compared to the tree inferred from the dataset excluding W. andersi (Fig. 6). The addition of the new species to the dataset has caused Ophioleucida O’Hara, Hugall, Thuy, Stöhr & Martynov, 2017 to form a sister group to the rest of the clade, albeit still paraphyletic for Ophiernidae O’Hara, Stöhr, Hugall, Thuy & Martynov, 2018, and the Ophiodermatina Ljungman, 1867 are left paraphyletic for Ophiomyxidae Ljungman, 1867. Ophiocopa spatula is morphologically similar to Ophiocamax vitrea Lyman, 1878 and thus clusters with Ophiocamacidae O’Hara, Stöhr, Hugall, Thuy & Martynov, 2018, leaving the Ophiotomidae paraphyletic. The addition of more species (Ophiactis profundi Lütken & Mortensen, 1899, two Ophiolimna, and O. spatula) has caused small changes in the tree structure and node support values, compared to previously published versions of the dataset (Thuy & Stöhr 2016; Stöhr 2024), but the division into major clades is the same. The dataset for W. andersi is incomplete and lacks all inner disc skeletal characters, because a lack of material did not allow the sacrifice of a specimen for dissociation of the disc ossicles. The homologies of the oral papillae could not be assessed, since the necessary ontogenetic series is not available, but the proximal papillae below the teeth were interpreted as tooth papillae and it is assumed that there should be infradental papillae and an adoral shield spine at the second tentacle scale. Incomplete data can have a negative effect on the analysis, as was also observed in the test run with only LAP characters (Supp. file 2), which resulted in a comb-shaped tree structure with broken up Amphilepidida O’Hara, Hugall, Thuy, Stöhr & Martynov, 2017. Only the Ophiacanthida still formed a clade similar to the complete analysis, and W. andersi is confirmed in the clade that contains the Ophiacanthida, but not within that order. Molecular data may also be needed, but the type material is suspected to have been preserved in denatured ethanol originally and none of the unique specimens could be sacrificed with such uncertain expected outcome.	en	Stöhr, Sabine (2025): Two new species of brittle stars (Echinodermata: Ophiuroidea), living epizoic on a stalked crinoid. European Journal of Taxonomy 1022: 176-201, DOI: 10.5852/ejt.2025.1022.3087, URL: https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/3087/13763
