identifier	taxonID	type	CVterm	format	language	title	description	additionalInformationURL	UsageTerms	rights	Owner	contributor	creator	bibliographicCitation
467887FDC3303A66FDD782F564BFF8FD.text	467887FDC3303A66FDD782F564BFF8FD.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Somasteroidea Spencer 1951	<div><p>KEY TO THE SOMASTEROIDEA SPENCER, 1951</p><p>1. Axial ossicles “ T ”-shaped, forming enlarged gaps (podial pores?) between sequential transverse ridges. First virgals enlarged, strongly differentiated. Virgal series not recognized proximally. Ambital framework ossicles proportionately large, abutted, aligned in linear series. Abactinals are tiny granules ........................................ ..................................................................................................................... monogeneric Archegonasteridae</p><p>— Axial ossicles square to weakly rectangular, few possible small podial pores recognized in two genera. First virgals at most weakly differentiated. Virgal series recognized proximally. Ambital framework ossicles small, otherwise varied. Abactinals are weakly enlarged spicules or platelets ........................ Chinianasteridae Spencer, 1951, 2</p><p>2. Overall form more nearly stellate, arms comparatively narrow. Ambital framework ossicles more robust, rod-like, elongate, overlapping but not irregular. Abactinals granular to plate-like, closely abutted, arrangement not reticulate .................................................................................... monogeneric, Ophioxenikosinae n. subfam.</p><p>— Overall form more nearly polygonal, arms comparatively broad. Ambital framework ossicles less robust, granular to weakly elongate, arrangement more or less irregular. Abactinals rod-like, spicular, arrangement reticulate, not closely abutted ............................................................................................................................................. 3</p><p>3. In oral view, axials “L”-shaped, podial basin proximal of transverse ridge ....................................................... ..................................................................................................... 2 genera, Villebrunasterinae Fell, 1963b, 4</p><p>— In oral view, axial interval abradial to radial channel bilateral; podial basins approximately shared by successive podial basins ............................................................................. 3 genera, Chinianasterinae Spencer, 1951, 5</p><p>4. Abradial adaxials variously differentiated, arrangement varied ............................ Villebrunaster Spencer, 1951</p><p>— Abradial adaxials uniform, arrangement uniform ...................................................... Ampullaster Fell, 1963b</p><p>5. Axials in aboral aspect shield-like and clearly overlapping distally, compound axials unknown. Abactinals comparatively less delicate. Madreporite where recognized on oral surface near but not abutting mouth frame. Ambital framework of many tiny platelets forming a complex apparently somewhat ill-defined series. Virgals moderately robust, rectangular; medial ridge lacking. Adjacent virgalia potentially forming a robust platform when deflected distally. “Radioles” not developed .................................................. Chinianaster Thoral, 1935</p><p>— Axials in aboral aspect approximately square in outline and weakly overlapping distally, compound axial known only at mouth frame. Abactinals comparatively more delicate. Madreporite where recognized on aboral surface away from central disk. Ambital framework ossicles numerous, small but not tiny, forming a complex well-defined series. Virgals stout, rectangular, with a medial ridge. Adjacent virgalia forming a platform with well-defined grooving shared by adjacent virgalia. “Radioles” not developed ...................................................................... ....................................................................................... Cantabrigiaster Hunter &amp; Ortega-Hernández, 2021</p><p>— Axials in aboral aspect approximately square in outline, at most weakly overlapping distally, compound axials can be developed at least near mouth frame. Abactinals comparatively more delicate. Madreporite not recognized. Ambital framework ossicles of many tiny platelets forming a complex apparently somewhat ill-defined series. Virgals very delicate, grooved, rodlike. Adjacent virgalia too slender to form a platform. An enlarged attenuated “radiole” can occur at the abradial termini of abutted virgalia ................... Thoralaster Dean Shackleton, 2005</p><p>Class SOMASTEROIDEA Spencer, 1951</p><p>DIAGNOSIS. — Overall form low arched; outline ranging from subpentagonal with arms broad, more abruptly tapering, to outline substellate, arms triangular, elongate, more gradually tapering. Abactinals small, individually irregular but aboral surface in total uniform. Abactinals divisible into three types: abactinals delicate, multiradiate, arrangement reticulate; abactinals closely fitted small platelets; enlarged primary abactinals absent, ossicles limited to granules. Abactinals not aligned in rows, carinal, centrale, and aboral ring differentiation unknown. Madreporite recognized in three genera. Ambital frameworks varied, ranging from complexly arranged tiny platelets to single well-defined abutted series. Axial positioning across arm midline irregular, locally clearly offset to nearly opposite. Axials not permanently vaulted to form a furrow, but arm and disk capable of facultative flexure as to yield temporary furrow-like configurations. Axials nearly equidimensional, form differing among genera. Axial radial water vascular channel large, closed or nearly closed over water-vascular tissues in most genera. Transverse water-vascular channel ill-defined. Transverse ridge generally narrow, podial basins large, deep in most genera. Mouth frame ossicles relatively small, differentiation from more distal axials comparatively limited. Mouth-angle ossicles upright; small spinelets can occur; podial basin of adjacent axial aligned with those of more distal axials. Axillary (odontophore) not recognized.Terminal ossicle problematic, not definitively recognized. Linear, transverse series of proportionately small rod-like ossicles (“virgals”, the single series a “virgalium”, plural “virgalia”) radiate abradially from each axial, the first of the series more (e.g. Archegonaster) or less (e.g. Chinianaster) clearly differentiated from the remainder of the series. Virgalia occupy the interspace between ambital framework and axials thereby occupying the oral disk plane: actinal ossicles not recognized. Virgalium in life capable of some rotation about the longitudinal axis, virgalia capable of coordinated series deflection in the body plane. Virgalia thought to be lacking proximally from one genus. Accessories limited to relatively small spinelets and granules.</p></div>	https://treatment.plazi.org/id/467887FDC3303A66FDD782F564BFF8FD	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Blake, Daniel B.;Lefebvre, Bertrand	Blake, Daniel B., Lefebvre, Bertrand (2025): The class Somasteroidea and its significance among early Asterozoa (Echinodermata). Comptes Rendus Palevol 24 (23): 449-487, DOI: 10.5852/cr-palevol2025v24a23, URL: https://doi.org/10.5852/cr-palevol2025v24a23
467887FDC3303A67FC7D85BF614DFD31.text	467887FDC3303A67FC7D85BF614DFD31.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Chinianasteridae Spencer 1951	<div><p>Family CHINIANASTERIDAE Spencer, 1951</p><p>Chinianasteridae Spencer, 1951: 93 .</p><p>Chinianasteridae restricted to Chinianaster Fell, 1963b: 144; Spencer &amp; Wright 1966: 39.</p><p>Chinianasteridae included Villebrunaster, Chinianaster, Thoralaster, Ophioxenikos: Dean Shackleton 2005: 30.</p><p>TYPE GENUS. — Chinianaster Thoral, 1935 .</p><p>TYPE SPECIES. — Chinianaster levyi Thoral, 1935 .</p><p>DIAGNOSIS. — Abactinal skeleton well-developed, consisting of many small, irregular but uniform ossicles. Ambital framework varied among genera, ossicles proportionately small, series well defined but ossicular arrangement irregular, varying among genera. Axials approximately equidimensional to rectangular; localized podial pores possibly occurring in two genera. Water-vascular channel skeletally closed orally. Virgalia reaching mouth frame. First virgal at most weakly differentiated.</p></div>	https://treatment.plazi.org/id/467887FDC3303A67FC7D85BF614DFD31	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Blake, Daniel B.;Lefebvre, Bertrand	Blake, Daniel B., Lefebvre, Bertrand (2025): The class Somasteroidea and its significance among early Asterozoa (Echinodermata). Comptes Rendus Palevol 24 (23): 449-487, DOI: 10.5852/cr-palevol2025v24a23, URL: https://doi.org/10.5852/cr-palevol2025v24a23
467887FDC3313A65FEE6879E623AF8A6.text	467887FDC3313A65FEE6879E623AF8A6.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Chinianaster levyi Thoral 1935	<div><p>Chinianaster levyi Thoral, 1935</p><p>(Figs 1A; 2; 3)</p><p>Chinianaster levyi Thoral, 1935: 127, pl. 9, fig. 1a, 1b; non pl. 8, fig. 1; non pl. 10, fig. 4. — Spencer 1951: 98, pl. 3, figs 35, 36, text-figs 7, 8, non pl.2, figs 32, 33. — Ubaghs 1953: 814, text fig. 17. — Fell 1963a: pars 393-403, fig. 8B, non 6E. — Spencer &amp; Wright 1966: U39, figs 8.2, 13, 19.1, 39.4. — Blake 1982: fig. 1E, non fig. 1C. — Dean Shackleton 2005: 68, pl. 3, figs 3, 4, text figs 5, 12B. — Blake 2013: 363, figs 1.1, 1.2. — Blake &amp; Guensburg 2015: 467, figs 1.1-1.6, 2.1-2.7, 3.1-3.4. — Blake 2018: 2, 21; pl. 1.1, 1.2, fig. 2.1. — Blake 2024: 2 et seq., pl. 2.1-2.3.</p><p>TYPE MATERIAL. — Lectotype. France • 1 specimen (specimen distorted, arm radii approximately 25 to 30 mm); Hérault, Saint-Chinian; Saint-Chinian Formation; Euloma filacovi Zone, late Tremadocian (Early Ordovician); Villebrun leg.; UCBL-FSL 168691 (Figs 2A1-4; 3A).</p><p>REFERRED SPECIMENS. — Eight specimens (UCBL-FSL 711093 [FSL 1879 553 of Dean Shackleton 2005], UCBL-FSL 711094 [FSL 1879 558 of Dean Shackleton 2005], UCBL-FSL 711095 [FSL 1879 563 of Dean Shackleton 2005], UCBL-FSL 712002- 712004, UCBL-FSL 712090, UCBL-FSL 713577. Questionable, four more specimens (MBB-GG20, MBB-GG23, UCBL-FSL 712017, UCBL-FSL 713576). Assignment of two more specimens is problematic (MBB-GG2, MBB-GG18).</p><p>TYPE LOCALITY AND HORIZON. — Saint-Chinian Formation, Early Ordovician (late Tremadocian); Saint-Chinian (Hérault), Montagne Noire, France.</p><p>DIAGNOSIS. — Abactinals moderately robust, arrangement quite closely reticular (Fig. 2A). Ambital framework ossicles tiny, plate-like; arrangement complex, series as preserved ill-defined, irregular (Fig.2 B-D). Axials in aboral view shield-like, successive axials overlapping (Fig. 2A). In oral view, compound axials not recognized. MAO not bearing an enlarged flange-like aboral process. Where not eroded, radial-water vascular channel enclosed at arm axis by an enclosing skeletal arch (Figs 2C, E; 3B, E). Adaxials moderately large, thin, broad surface longitudinally grooved, groove broad (Figs 2E; 3C).</p><p>DESCRIPTION</p><p>Overall form in life low-arched, outline subpentagonal; arms broad, triangular, taper gradual. Abactinals spiculate, multiradiate, rod-like abactinals likely developed; abactinal arrangement open hexagonal reticular. Madreporite on oral surface offset from MAO, surface texture granular (Figs 2C; 3A, B). Ambital framework a continuous well-defined but irregular necklace of tiny platelets; ambital framework not deflected toward mouth frame to form a gap or cleft (Fig. 2 B-D). In aboral aspect, axials shield-like, surface curved, sequential axials overlapping, axial series longitudinally grooved approximately at position of abradial margin of podial basins; proximal axials with possible podial pore (Fig. 2A, F). In oral aspect, where preserved (generally distally), radial water-vascular channel oral surface closed by shield-like skeletal arch (Figs 2C, E; 3B); where shield eroded (generally proximally) and axial series dilated, axials appearing approximately double-bilateral along and normal to transverse ridge; podial basin boundary medial; abradial margin concave.MAO proportionately small, appearing plate-like where directed toward mouth, rounded where deflected toward interior; lateral margins concave for tube foot; differentiation of circumoral appearing limited (Fig. 3E). Virgalia abutting abradial terminus of axial transverse ridge, virgalia reaching mouth frame (Figs 2B; 3B, C, E). Virgals relatively thin, rectangular, planar, grooved, termini expanded; virgals when rotated to exposed broad surface potentially robust enough as to have formed a continuous platform at least where deflected distally. First virgals less elongate than more lateral virgals, otherwise similar. Virgal accessories, if any, small, granular.</p><p>REMARKS</p><p>The concept of Thoralaster Dean Shackleton 2005, was based on a part of the Chinianaster type suite, see under that genus. Shield-like overlapping axials and flat, rectangular adaxials provide guides to the recognition of Chinianaster . Although uncommonly clearly preserved, an ambital framework of fine platelets is shared only with Thoralaster . Dean Shackleton (2005: 68 R), however, posited presence of robust marginals in Chinianaster, some a “large spike”. The interpretation appears to have been based on her figure 5B (p. 40), the apparent interval illustrated here (Fig. 2F) in which ossicles are displaced and enlarged “spikes” are found at the arm tip. Spike identity is uncertain but more proximal ossicles argue terminal ossicles of virgalia, the ambital necklace all but lost from this specimen (Fig. 2F). A single ossicle at the arm tip of a Chinianaster or near- Chinianaster specimen (Fig. 14H) suggests a spike-like terminal. Dean Shackleton (2005) interpreted virgalia as lacking at the mouth frame of Chinianaster; although largely disrupted, remnants of virgalia are common, including in the lectotype (Fig. 2C, D).</p></div>	https://treatment.plazi.org/id/467887FDC3313A65FEE6879E623AF8A6	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Blake, Daniel B.;Lefebvre, Bertrand	Blake, Daniel B., Lefebvre, Bertrand (2025): The class Somasteroidea and its significance among early Asterozoa (Echinodermata). Comptes Rendus Palevol 24 (23): 449-487, DOI: 10.5852/cr-palevol2025v24a23, URL: https://doi.org/10.5852/cr-palevol2025v24a23
467887FDC3313A67FEE186F9611DFAC5.text	467887FDC3313A67FEE186F9611DFAC5.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Chinianaster Thoral 1935	<div><p>Genus Chinianaster Thoral, 1935</p><p>Chinianaster Thoral, 1935: 127 .</p><p>DIAGNOSIS. — As for Chinianaster levyi, the type and only recognized species.</p></div>	https://treatment.plazi.org/id/467887FDC3313A67FEE186F9611DFAC5	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Blake, Daniel B.;Lefebvre, Bertrand	Blake, Daniel B., Lefebvre, Bertrand (2025): The class Somasteroidea and its significance among early Asterozoa (Echinodermata). Comptes Rendus Palevol 24 (23): 449-487, DOI: 10.5852/cr-palevol2025v24a23, URL: https://doi.org/10.5852/cr-palevol2025v24a23
467887FDC3313A67FF2380FB624AFB23.text	467887FDC3313A67FF2380FB624AFB23.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Chinianasterinae Spencer 1951	<div><p>Subfamily CHINIANASTERINAE Spencer, 1951</p><p>Chinianasteridae Spencer, 1951, here recognized at the subfamily level for Chinianaster, Cantabrigiaster, and Thoralaster .</p><p>TYPE GENUS. — Chinianaster Thoral, 1935 .</p><p>TYPE SPECIES. — Chinianaster levyi Thoral, 1935 .</p><p>DIAGNOSIS. — Subpentagonal Chinianasteridae . Abactinals spiculate, arrangement reticulate. Ambital framework ossicles tiny, granular or plate-like; overall arrangement thought irregular. Radial water vascular canal large, skeletally delicate, closed orally, where closure was diagenetically lost abradial portion of ossicle doubly bilateral at midpoint of transverse ridge. Podial basin boundary approximately medial, basin shared equally by successive axials. Adradial adaxials weakly differentiated, virgalia relatively elongate.</p></div>	https://treatment.plazi.org/id/467887FDC3313A67FF2380FB624AFB23	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Blake, Daniel B.;Lefebvre, Bertrand	Blake, Daniel B., Lefebvre, Bertrand (2025): The class Somasteroidea and its significance among early Asterozoa (Echinodermata). Comptes Rendus Palevol 24 (23): 449-487, DOI: 10.5852/cr-palevol2025v24a23, URL: https://doi.org/10.5852/cr-palevol2025v24a23
467887FDC3333A65FEBE857F6402F998.text	467887FDC3333A65FEBE857F6402F998.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Cantabrigiaster Hunter & Ortega-Hernandez 2021	<div><p>Genus Cantabrigiaster Hunter &amp; Ortega-Hernández, 2021</p><p>Cantabrigiaster Hunter &amp; Ortega-Hernández, 2021: 2 .</p><p>Villebrunaster Blake &amp; Hotchkiss, 2022: 30 .</p><p>TYPE SPECIES. — Cantabrigiaster fezouataensis Hunter &amp; Ortega-Hernández, 2021 .</p><p>DIAGNOSIS. — As for Cantabrigiaster fezouataensis, the type and only recognized species.</p></div>	https://treatment.plazi.org/id/467887FDC3333A65FEBE857F6402F998	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Blake, Daniel B.;Lefebvre, Bertrand	Blake, Daniel B., Lefebvre, Bertrand (2025): The class Somasteroidea and its significance among early Asterozoa (Echinodermata). Comptes Rendus Palevol 24 (23): 449-487, DOI: 10.5852/cr-palevol2025v24a23, URL: https://doi.org/10.5852/cr-palevol2025v24a23
467887FDC3333A60FC3E845F6485FC05.text	467887FDC3333A60FC3E845F6485FC05.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Cantabrigiaster fezouataensis Hunter & Ortega-Hernandez 2021	<div><p>Cantabrigiaster fezouataensis Hunter &amp; Ortega-Hernández, 2021</p><p>(Figs 4; 5)</p><p>Cantabrigiaster fezouataensis Hunter &amp; Ortega-Hernández, 2021: 2, fig. 1; electronic supplemental material.</p><p>Villebrunaster fezouataensis — Blake &amp; Hotchkiss 2022: 29, figs 2-5.</p><p>TYPE MATERIAL. — Holotype. Morocco • 1 specimen (only oral surface, good preservation of ossicular detail; arm radius R 27 mm; disk radius r 18 mm; both measurements and especially that of the latter extended by sediment compaction); Central Anti-Atlas, Ternata plain (north of Zagora); Sagenograptus murrayi Zone, late Tremadocian (Early Ordovician); 2003, Van Roy leg.; UCBL-FSL 424961 (Fig. 4 A-D).</p><p>REFERRED SPECIMENS. — 34 specimens (MHNN.P.045596, PRIP 20026-20027, PRIP 20028.1-6; PRIP 20029.1-2, PRIP 20030.1- 2, UCBL-FSL 424962, UCBL-FSL 711937-711939, UCBL-FSL 711945-711946, YPM IP 535545-535559) .</p><p>TYPE LOCALITY AND HORIZON. — Fezouata Formation, Early Ordovician (late Tremadocian); Ternata plain, Zagora area, Anti-Atlas, Morocco.</p><p>DIAGNOSIS. — Abactinal arrangement open reticular (Figs 4F; 5A, C, D). Ambital framework ossicles small, granular, complexly overlapping but closely abutted as to form a clearly defined series (Figs 4E; 5A, D, E). Axials in aboral view rectangular, successive axials abutted, not notably overlapping (Fig. 5A). In oral view, compound axials can occur at mouth frame (Fig. 4C). Radial water-vascular channel narrowly enclosed at arm axis (Figs 4A, C; 5A). Adaxials strongly robust, rectangular, longitudinal ridges well-defined, adjacent abutted virgalia forming a transverse well-defined groove, abutted virgalia forming a distinct platform (Figs 4A, B; 5D, E).</p><p>DESCRIPTION</p><p>Overall form in life low-arched, outline subpentagonal; arms broad, short, triangular.Abactinals rod-like; multiradiate abactinals not identified. Only identified madreporite (Fig. 5A, B) aboral, surface texture granular, madreporite offset from central area of disk.Ambital framework well-defined, marginal series forming a continuous pentagonal outline extending around the arm tip, series not deflected toward mouth frame to form gap or cleft. Ambital framework ossicles small, numerous, equidimensional, granular to weakly elongate; ossicles overlapping, not differentiated as to suggest inferomarginals and superomarginals.</p><p>In aboral aspect, axials nearly paired or slightly offset across arm midline, axial outline nearly square, sequential axials abutted; axial series (only where better preserved?) appearing longitudinally grooved. In oral aspect, axial outline approximately rectangular, water vascular channel large, enclosed. Axial transverse ridge narrow, axial approximately doubly bilateral at midpoint of transverse ridge, podial basin large, equally shared by subsequent axials, transverse ridge flared abradially to form concave seat for virgalium. Compound axial can occur at mouth frame. Terminal not recognized. First virgals smaller than but similar to more abradial; all virgals robust, rectangular, bearing a medial ridge and lateral groove shared by adjacent virgalia, ossicular boundaries approximately medial in groove. As typically preserved, adjacent virgalia deflected distally as to form a pavement. Accessories not clearly identified, some circular pustules and circular depressions might favor accessories.</p><p>REMARKS</p><p>A posited absence of an ambital framework was foundational to the recognition of Cantabrigiaster fezouataensis, and putative absence essential to Cantabrigiaster assignment to a basal position within Somasteroidea . Presence of an ambital framework similar to that of Villebrunaster was documented in the holotype and other specimens of the type suite, and with emphasis on the framework, Cantabrigiaster was synonymized with Villebrunaster (Blake &amp; Hotchkiss 2022) . Herein, axial and adaxial expressions are argued as providing essential guides to asterozoan affinities (e.g. Blake 2013, 2018, 2024; Blake &amp; Guensburg 2015; Glass et al. 2024), the differences between Cantabrigiaster and other somasteroids calling for generic recognition.</p><p>Most distinctive, the robust adaxials of Cantabrigiaster differ from those of other somasteroid genera in both form and arrangement, with adjacent virgalia abutted laterally to form a robust platform. The ambital framework of Cantabrigiaster differs from those of Chinianaster, Villebrunaster, and Ampullaster in ossicular shape but not in overall series configuration. Surface texture of the madreporite (Fig. 5A, B) is similar to that of Chinianaster (Fig. 3A, B) although the two differ in madreporite positioning. Axial series offset and disruption of more proximal abactinals of the only Cantabrigiaster example exhibiting a madreporite indicate some displacement accompanied preservation, the present positioning therefore of unknown general significance.</p></div>	https://treatment.plazi.org/id/467887FDC3333A60FC3E845F6485FC05	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Blake, Daniel B.;Lefebvre, Bertrand	Blake, Daniel B., Lefebvre, Bertrand (2025): The class Somasteroidea and its significance among early Asterozoa (Echinodermata). Comptes Rendus Palevol 24 (23): 449-487, DOI: 10.5852/cr-palevol2025v24a23, URL: https://doi.org/10.5852/cr-palevol2025v24a23
467887FDC3363A60FC7A81D863F3FB6E.text	467887FDC3363A60FC7A81D863F3FB6E.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Thoralaster Dean Shackleton 2005	<div><p>Genus Thoralaster Dean Shackleton, 2005</p><p>Thoralaster Dean Shackleton 2005: 68 .</p><p>TYPE SPECIES. — Thoralaster spiculiformis Dean Shackleton, 2005 .</p><p>DIAGNOSIS. — As for Thoralaster spiculiformis, the type and only recognized species.</p></div>	https://treatment.plazi.org/id/467887FDC3363A60FC7A81D863F3FB6E	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Blake, Daniel B.;Lefebvre, Bertrand	Blake, Daniel B., Lefebvre, Bertrand (2025): The class Somasteroidea and its significance among early Asterozoa (Echinodermata). Comptes Rendus Palevol 24 (23): 449-487, DOI: 10.5852/cr-palevol2025v24a23, URL: https://doi.org/10.5852/cr-palevol2025v24a23
467887FDC3363A6CFC95873E6200FA07.text	467887FDC3363A6CFC95873E6200FA07.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Thoralaster spiculiformis Dean Shackleton 2005	<div><p>Thoralaster spiculiformis Dean Shackleton, 2005</p><p>(Figs 1B; 6-8)</p><p>Chinianaster levyi Thoral, 1935, pl. 8, fig.1. — Spencer 1951: pl. 2.32, 2.33.— Fell 1963a: fig. 6E. — Blake 1982: fig. 4C.</p><p>Thoralaster spiculiformis Dean Shackleton, 2005: 68, pl, 4.1-4.6, fig. 7. — Blake 2013: fig. 1.6. — Blake &amp; Guensburg 2015: 472, figs 5.1-5.5, 6.1-6.8.</p><p>TYPE MATERIAL. — Holotype. France • 1 specimen (part and counterpart); Hérault, Saint-Chinian, La Croix-Rouge; Euloma filacovi Zone, late Tremadocian (Early Ordovician); 1953, Thoral leg.; UCBL-FSL 168697 (“ES1” of Dean Shackleton 2005); (Fig. 6A1-6).</p><p>Paratype. France • 1 specimen; Hérault, Saint-Chinian; Euloma filacovi Zone, late Tremadocian (Early Ordovician); 1879, Lignières leg.; UCBL-FSL 711096 (“FSL 1879 564” of Dean Shackleton 2005) (Fig. 7B) .</p><p>REFERRED SPECIMENS. — Five specimens (UCBL-FSL 168690, UCBL-FSL 424943, UCBL-FSL 712005, MNHN.F.A90271, MNHN.F.A97739) .</p><p>TYPE LOCALITY AND HORIZON. — Saint-Chinian Formation, Early Ordovician (late Tremadocian); La Croix-Rouge, E of Saint-Chinian (Hérault), Montagne Noire, France.</p><p>DIAGNOSIS. — Abactinals delicate, arrangement open reticular (Fig. 7 A-C). Ambital framework ossicles tiny, plate-like, arrangement complex, series as preserved ill-defined, irregular (Figs 6 D-F; 7A, C, E, F). Radial-water vascular channel narrowly enclosed at arm axis (Fig. 8D, distal). In oral view, compound axials recognized near mouth frame (Figs 1B; 6 A-C; 8D). MAO bearing an enlarged flange-like aboral process (Figs 7A, C; 8A, C, E). Adaxials very delicate, rodlike, longitudinal groove narrow (Figs 1B; 6B, F; 7A, C; 8B).</p><p>DESCRIPTION</p><p>Overall form low-arched, outline substellate, arm outline in life thought to be triangular, moderately abruptly tapering. Abactinals delicate, spiculate, configuration open hexagonal reticular. Madreporite unknown. Ambital framework forming a continuous, well-defined, irregular necklace of tiny platelets, series not deflected toward mouth frame to form a gap or cleft. In aboral aspect, axial ossicles shield-like, sequential ossicles weakly overlapping (Figs 6F; 7 A-C; 8A, C, E), axial series longitudinally weakly grooved (Fig. 8A). In oral aspect, radial water vascular channel closed (near arm tips, Figs 6A; 7A; 8D, F). Some axials compound, i.e., bearing more than a portion of a podial basin on each side of the transverse ridge (Figs 1B; 6A, C; 8D); non-compound axials appearing approximately double-bilateral along and normal to the transverse ridge; podial basin boundary medial, abradial axial margin concave. Mouth-angle ossicle transverse ridges converge abradially in an “A”-frame-like pattern (Fig. 8D). Ossicle immediately adjacent to MAO (i.e., circumoral?) strongly flared as to yield an appearance suggestive of an open bivalve (Figs 7A, C; 8A, C, E). First subsequent axial similar to those of remainder of series, podial basin aligned with those of subsequent axials (Figs 7D, E; 8D, F). Virgalia abutting abradial terminus of axial transverse ridge, concentration of debris arguing virgalia reached mouth frame (Figs 6A; 7D; 8A, B). Virgals proportionately very small, delicate, rod-like, grooved longitudinally, termini weakly expanded; first virgals short, otherwise similar to more lateral virgals. Virgalia too delicate to have formed an abutted platform. Some adjacent virgalia termini abutted abradially to support an enlarged, attenuated, distal “radiole” (Fig. 6B, D, F). Virgal accessories small, plate-like to granular (Figs 1B; 6B, D, F).</p><p>REMARKS</p><p>The concept of Thoralaster was based on a few specimens taken from the type suite of Chinianaster (Dean Shackleton 2005); additional specimens are included here.</p><p>The clearest criterion for specimen inclusion is presence of an enlarged, flanged surface suggestive of an open bivalve in the mouth frame, it most readily viewed in aboral aspect. Because variously preserved among specimens, it is unclear whether the flange is a part of the MAO or a separate ossicle, as is suggested by discontinuities (Figs 7C; 8C), the flange then either the circumoral or a supernumerary</p><p>Additional generic criteria include presence of proportionately large, delicate axials, some compound in that the ossicle bears more than a partial podial basin on each side of the transverse ridge. Adaxials are very slender and rod-like.Perhaps suggesting structural integrity, most arm tips of Thoralaster held together during diagenesis, the axial series on the sides of the arm as preserved more (Figs 6A; 7A) or less (Fig. 8A) strongly diverging toward the disk. Although recognized only in a single arm interval and thereby potentially indicative of a transitional state, positioning and regularity of expression of apparent openings suggest podial pores (Fig. 8H). As compared to other somasteroid genera, overall construction of Thoralaster was somewhat delicate.</p></div>	https://treatment.plazi.org/id/467887FDC3363A6CFC95873E6200FA07	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Blake, Daniel B.;Lefebvre, Bertrand	Blake, Daniel B., Lefebvre, Bertrand (2025): The class Somasteroidea and its significance among early Asterozoa (Echinodermata). Comptes Rendus Palevol 24 (23): 449-487, DOI: 10.5852/cr-palevol2025v24a23, URL: https://doi.org/10.5852/cr-palevol2025v24a23
467887FDC33A3A6CFC5C83BA63D7FDC8.text	467887FDC33A3A6CFC5C83BA63D7FDC8.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Villebrunaster Spencer 1951	<div><p>Genus Villebrunaster Spencer, 1951</p><p>Villebrunaster Spencer, 1951: 93 .</p><p>TYPE SPECIES. — Villebrunaster thorali Spencer, 1951 .</p><p>DIAGNOSIS. — As for Villebrunaster thorali, the type and only known species.</p></div>	https://treatment.plazi.org/id/467887FDC33A3A6CFC5C83BA63D7FDC8	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Blake, Daniel B.;Lefebvre, Bertrand	Blake, Daniel B., Lefebvre, Bertrand (2025): The class Somasteroidea and its significance among early Asterozoa (Echinodermata). Comptes Rendus Palevol 24 (23): 449-487, DOI: 10.5852/cr-palevol2025v24a23, URL: https://doi.org/10.5852/cr-palevol2025v24a23
467887FDC33A3A6CFF2787DE6454FEF8.text	467887FDC33A3A6CFF2787DE6454FEF8.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Villebrunasterinae Fell 1963	<div><p>Subfamily VILLEBRUNASTERINAE Fell, 1963b</p><p>Villebrunasterinae Fell, 1963b: 143 .</p><p>TYPE GENUS. — Villebrunaster Spencer, 1951 .</p><p>DIAGNOSIS. — Subpentagonal Chinianasteridae . Abactinals spiculate, arrangement reticulate. Ambital framework ossicles granular to somewhat elongate, overall arrangement somewhat irregular, ossicles overlapping. Radial water-vascular channel large, cylindrical, robust; axials asymmetrical. Podial basin on proximal side of transverse ridge. Adradial adaxials complexly differentiated, virgalia relatively elongate.</p><p>REMARKS</p><p>The Villebrunasterinae is separated from both the Chiniasterinae and the Ophioxenikosinae n. subfam. based on axial and adradial virgal differentiation, the Ophioxenikosinae n. subfam. further differing in form, abactinal, and ambital framework expressions. The Villebrunasterinae and Chiniasterinae earlier were recognized at the familial level (Fell 1963b; Spencer &amp; Wright 1966).</p></div>	https://treatment.plazi.org/id/467887FDC33A3A6CFF2787DE6454FEF8	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Blake, Daniel B.;Lefebvre, Bertrand	Blake, Daniel B., Lefebvre, Bertrand (2025): The class Somasteroidea and its significance among early Asterozoa (Echinodermata). Comptes Rendus Palevol 24 (23): 449-487, DOI: 10.5852/cr-palevol2025v24a23, URL: https://doi.org/10.5852/cr-palevol2025v24a23
467887FDC33A3A68FC5680BB6295FBC5.text	467887FDC33A3A68FC5680BB6295FBC5.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Villebrunaster thorali Spencer, Saint-Chinian Formation, Early Ordovician 1951	<div><p>Villebrunaster thorali Spencer, 1951</p><p>(Figs 9-12)</p><p>Chinianaster levyi Thoral, 1935: pars 127, pl. 10.4, UCBL-FSL 168698.</p><p>Villebrunaster thorali Spencer, 1951: 93, pl. 2, figs 29-31, text-figs 1, 3, 4. — Fell 1963a: 393 et seq., figs 6B, 6C, 8C. — Spencer &amp; Wright 1966: 41, figs 8.1a, 8.1b, 39.1. — Blake 2013: 363, fig. 1.3-1.5. — Blake &amp; Guensburg 2015: 472, fig. 5.1-5.6, 6.1-6.8.</p><p>Villebrunaster Spencer, 1951 — Blake 2018: 7, pl. 1.3. — Blake 2024: 4 et seq., fig. 1.1; pl. 2.9-2.12, non 1.1.</p><p>TYPE MATERIAL. — Holotype. France • 1 specimen (individual with five arms preserved; in the same concretion as paratype UCBL-FSL 168692a.2, see below); Hérault, Saint-Chinian, La Croix-Rouge; Euloma filacovi Zone, late Tremadocian (Early Ordovician); 1953, Thoral leg.; UCBL-FSL 168692a.1 (Fig. 9A, C-E).</p><p>Paratype. France • 1 specimen (only two arms preserved; part and counterpart with different registration numbers, see below); Hérault, Saint-Chinian, La Croix-Rouge; Euloma filacovi Zone, late Tremadocian (Early Ordovician); 1953, Thoral leg.; UCBL-FSL 168692a.2 (part) and UCBL-FSL168693c (counterpart) .</p><p>REFERRED SPECIMENS. — Six specimens (UCBL-FSL 168693, UCBL-FSL 168698, UCBL-FSL 424948, UCBL-FSL 711092 [FSL 1879 561 of Dean Shackleton 2005], MNHN.F.A47188, MNHN.F.A97740) .</p><p>DIAGNOSIS. — Abactinal arrangement open reticular (Figs 10B; 11A; 12F). Ambital framework ossicles equidimensional to somewhat rodlike and elongate, abutted to weakly overlapping (Figs 9A; 10A; 11A, D; 12E, F). Axials in aboral view only exposing square surface over water-vascular channel, the transverse ridge obscured; series grooved longitudinally (Figs 10B; 11A; 12F). In oral view, compound axials not recognized; radial-water vascular channel cylindrical, transverse ridge narrow, podial basin proximal (Figs 9; 10A, C; 12B, D). Adaxials moderately large, thin, broad surface longitudinally broadly grooved (Figs 9C; 10B, C; 11C, D; 12B). Adradial-most adaxial configurations not uniform but complexly varied both within and among specimens (Figs 9; 10; 11C; 12B, D).</p><p>DESCRIPTION</p><p>Overall form in life low-arched, outline subpentagonal; arms broad, triangular, taper gradual. Abactinals delicate, spiculate, rod-like and multiradiate; abactinal arrangement open hexagonal reticular. Madreporite, if any, unknown. Ambital framework well-defined and forming a continuous pentagonal series extending around the arm tip, the series not deflected toward the mouth frame to form a gap or cleft. Marginal ossicles granular to rod-like, abutted to overlapping.</p><p>Axials in aboral aspect appearing approximately square, sequential axials abutted, longitudinal grooving weakly expressed, transverse ridge in aboral aspect generally obscured as preserved. Axials in oral aspect of an “L”-shape, form dominated by cylindrical water-vascular skeletal closure; transverse ridge generally appearing short, linear to recurved (Fig. 9A, B; 10C, D); podial basin on proximal side of transverse ridge. Mouth-angle ossicles when extended toward mouth area appearing relatively narrow, abutted, upright, bearing simple accessory spinelets (Fig. 11B). Next ossicular pair (circumoral?) upright, abutted at arm midline, proximal margins curved (Fig. 11A, B); possible small ossicle (Fig. 11B) might represent circumoral. Terminal, if differentiated, obscure (Figs 11A; 12F). Adradial-most virgals judged variably differentiated and variably linked to axials, possibly locally with an embedded virgal equivalent between the axial and a more strongly differentiated second ossicle (Fig. 12B). Abradial virgals elongate, grooved, sub-planar, termini expanded, rectangular in outline, edges narrow in ossicles rotated laterally; adjacent virgalia not closely spaced, perhaps not close enough to have formed a continuous platform when deflected distally. Localized alignment of granular debris suggests presence of virgal accessories. Other possible accessories not recognized.</p><p>REMARKS</p><p>Interpretation of Villebrunaster and Ampullaster is entangled in a number of morphological complexities as well as the uncertainties of preservation. Villebrunaster is most clearly differentiated by axial shape and complexities of the immediately adjacent adaxials. The axial transverse ridge can be recurved as to partially enclose podial basins (Figs 9A, B; 10C, D). The apparent circumoral is enlarged, the adoral edge curved, thereby potentially reflecting presence of a podium directed toward the mouth. An apparent small ossicle is developed between the MAO and the “circumoral” (Fig. 11B), it potentially the homologue of the enlarged flange or circumoral of Thoralaster (Fig. 7A, C). Madreporite presence in Villebrunaster was noted but not illustrated (Dean Shackleton 2005, char. 77), and no example was recognized here. The ambital framework of Villebrunaster is well-defined but somewhat irregular, locally appearing to form a linear series, locally appearing slightly overlapping. Small virgal accessories occur (Fig. 10C, D). Marginal and abactinal accessories are not recognized although widely occurrent fine debris might indicate presence.</p></div>	https://treatment.plazi.org/id/467887FDC33A3A68FC5680BB6295FBC5	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Blake, Daniel B.;Lefebvre, Bertrand	Blake, Daniel B., Lefebvre, Bertrand (2025): The class Somasteroidea and its significance among early Asterozoa (Echinodermata). Comptes Rendus Palevol 24 (23): 449-487, DOI: 10.5852/cr-palevol2025v24a23, URL: https://doi.org/10.5852/cr-palevol2025v24a23
467887FDC33E3A68FED186996135FAD5.text	467887FDC33E3A68FED186996135FAD5.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Ampullaster Fell 1963	<div><p>Genus Ampullaster Fell, 1963b</p><p>Villebrunaster — Dean Shackleton 2005: 64.</p><p>TYPE SPECIES. — Ampullaster ubaghsi Fell, 1963b .</p><p>DIAGNOSIS. — As for Ampullaster ubaghsi, the type and only recognized species.</p></div>	https://treatment.plazi.org/id/467887FDC33E3A68FED186996135FAD5	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Blake, Daniel B.;Lefebvre, Bertrand	Blake, Daniel B., Lefebvre, Bertrand (2025): The class Somasteroidea and its significance among early Asterozoa (Echinodermata). Comptes Rendus Palevol 24 (23): 449-487, DOI: 10.5852/cr-palevol2025v24a23, URL: https://doi.org/10.5852/cr-palevol2025v24a23
467887FDC33E3A57FEE7879E61DFFE5B.text	467887FDC33E3A57FEE7879E61DFFE5B.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Ampullaster ubaghsi Fell 1963	<div><p>Ampullaster ubaghsi Fell, 1963b</p><p>(Fig. 13)</p><p>Ampullaster ubaghsi Fell, 1963b: 145, pl. 1; fig. 1. — Fell 1963a: fig. 6A,D. — Spencer &amp; Wright 1966: 41, fig. 48. — Blake 1982: fig. 1D.</p><p>Villebrunaster thorali Spencer, 1951 — Dean Shackleton 2005): 64, pl. 3, fig. 6; non pl. 3, fig. 7, text-figs 2B, 6. — Blake &amp; Guensburg 2015: 472.</p><p>TYPE MATERIAL. — Holotype. France • 1 specimen (oral surface exposed; much ossicular surface detail lost); Hérault, Saint-Chinian; Euloma filacovi Zone, late Tremadocian (Early Ordovician); Villebrun leg.; UCBL-FSL 168673 (Fig. 13 A-D).</p><p>DIAGNOSIS. — First virgals aligned in well-defined series between successive virgalia; first virgals uniform, longitudinally elongate and shelf-like, possibly exhibiting an outer rim edging an inner, inclined surface.Marginals appearing small, irregular, perhaps weakly elongate; overall, marginal series uniform. Abradial virgals possibly relatively slender, otherwise similar to Villebrunaster .</p><p>DESCRIPTION</p><p>Overall form in life low-arched, outline subpentagonal; arms broad, triangular, taper gradual. Abactinals spiculate, rod-like, arrangement reticulate. Ambital framework of relatively small, irregular, granular to rod-like ossicles forming a well-defined marginal series continuous across the interbrachia, not deflected toward mouth frame to form a gap or cleft. In oral aspect, axials “L”-shaped, form dominated by enlarged, skeletally closed, cylindrical water-vascular channel. Transverse ridge narrow, linear. Lateral edges of first virgals narrow, bar-like. Abradial virgals potentially extremely slender, elongate, rod-like. Accessories not clearly recognized, some debris suggests possible presence.</p><p>REMARKS</p><p>Ampullaster is known only from the holotype, it nearly complete and exposed in oral aspect. At the time of recognition, both Ampullaster and Villebrunaster were assigned to a new Villebrunasteridae (Fell, 1963b) . Dean Shackleton (2005: 68), however, synonymized Ampullaster with Villebrunaster based primarily on equating differentiated adradial ossicles found in both as so-called “intervirgal struts”. The interpretation of Dean Shackleton earlier was accepted (Blake &amp; Guensburg 2015) but it is rejected here, the intervirgal struts reinterpreted as adradial adaxials rather than calling for a new ossicular category.</p><p>The adradial adaxials of the two generic designates are argued as differing enough in morphology and positioning as to be treated as independently derived from a more stemward state (e.g. such as that of Chinianaster), thereby justifying retention of the generic status of Ampullaster . The so-called “intervirgal struts” of Villebrunaster are much varied in shape and orientation both among and within individuals (Figs 9A; 10; 11C; 12B), whereas corresponding ossicles of Ampullaster (Fig. 13) are regular in form and arrangement, each forming a shelf that partially confines the podial basin in a manner suggestive of expressions found in stenuroids (Spencer 1940: fig. 331; Blake 2024). No direct linkage between somasteroids and stenuroids is suggested. Other apparent adaxial variants are found in Chinianaster (Fig. 2A), in a Chinianaster -like unassigned specimen (Fig. 14G), and different adaxial specializations have been recognized in a number of problematic early asterozoans (e.g. Blake et al. 2020; Blake 2024). Adaxial differentiation thus was widespread not only within the Somasteroidea but also among early asterozoans in general, the varied specializations affording apomorphies serving to differentiate among both class-level asterozoan entities as well as a few genera not assigned at the class level (Blake 2013, 2018, 2024).</p><p>Further potentially contributing to generic separation, marginals of Ampullaster appear smaller and more irregular than those of Villebrunaster . Abradial virgals of the Ampullaster appear slender and rod-like; if, however, these are similar to virgals of Villebrunaster and Chinianaster and were rotated into plan view, they might prove comparable, as is suggested by a small area of the holotype (Fig. 13B, lower right). Added comments are included above under “Adaxial skeleton.”</p><p>In the original diagnosis of Fell (1963b), marginal series were interpreted as edging deep interradial “V”-shaped “clefts” that produced petaloid arm outlines. It is argued here that the ambital framework was continuous across the interbrachium, as in all somasteroids. Fell (1963b) envisioned presence of gradational changes of axial expression along the length of the arm of Ampullaster, the most important the presence of skeletal discontinuities interpreted as podial pores. The interpretation is not accepted here.</p></div>	https://treatment.plazi.org/id/467887FDC33E3A57FEE7879E61DFFE5B	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Blake, Daniel B.;Lefebvre, Bertrand	Blake, Daniel B., Lefebvre, Bertrand (2025): The class Somasteroidea and its significance among early Asterozoa (Echinodermata). Comptes Rendus Palevol 24 (23): 449-487, DOI: 10.5852/cr-palevol2025v24a23, URL: https://doi.org/10.5852/cr-palevol2025v24a23
467887FDC3013A57FC8F80DB63CAFB44.text	467887FDC3013A57FC8F80DB63CAFB44.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Archegonasteridae Spencer 1951	<div><p>Family ARCHEGONASTERIDAE Spencer, 1951</p><p>Archegonasteridae Spencer, 1951: 101 .</p><p>TYPE GENUS. — Archegonaster Jaekel, 1923 .</p><p>DIAGNOSIS. — Abactinal skeleton limited to tiny granules. Ambital framework ossicles proportionately large, angular, forming a linear sequence. Axials “T”-shaped, gaps between successive axials suggesting podial pores. Water-vascular channel not skeletally closed orally. Virgalia not known to reach mouth frame. First virgal strongly differentiated.</p><p>REMARKS</p><p>For purposes of comparison, the diagnosis is written in parallel with that for the Chinianasteridae . The Archegonasteridae is known only from A. pentagonus; the diagnosis applies at the species level.</p></div>	https://treatment.plazi.org/id/467887FDC3013A57FC8F80DB63CAFB44	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Blake, Daniel B.;Lefebvre, Bertrand	Blake, Daniel B., Lefebvre, Bertrand (2025): The class Somasteroidea and its significance among early Asterozoa (Echinodermata). Comptes Rendus Palevol 24 (23): 449-487, DOI: 10.5852/cr-palevol2025v24a23, URL: https://doi.org/10.5852/cr-palevol2025v24a23
467887FDC3013A57FF5286F963D4FD1B.text	467887FDC3013A57FF5286F963D4FD1B.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Ophioxenikos langenheimi Blake & Guensburg 1993	<div><p>Ophioxenikos langenheimi Blake &amp; Guensburg, 1993</p><p>starfish Byrd, 1970: 29, fig. 5.</p><p>Ophioxenikos langenheimi Blake &amp; Guensburg, 1993: 109, figs 2.1-2.3, 2.5, 3. — Dean Shackleton 2005: 71, pl. 3.5. — Blake &amp; Guensburg 2015: 470, fig. 4.1.</p><p>TYPE MATERIAL. — Holotype. United States • 1 specimen; south-central Nevada, Ely Springs Mountain Range; Lower Pogonip Group, late early to middle Floian (Early Ordovician); PRIP UI X-4751.</p><p>TYPE LOCALITY AND HORIZON. — Lower Pogonip Group, Early Ordovician (late early to middle Floian); Ely Springs Mountain Range, south-central Nevada, United States.</p><p>DESCRIPTION</p><p>Overall form in life low-arched, outline substellate; arm outline in life triangular, quite abruptly tapering. Abactinals irregular, abutted, small, granular to plate-like. Madreporite unknown. Ambital framework well-defined, series forming a continuous outline extending around the arm tip, not deflected toward the mouth frame; marginals rod-like, robust, overlapping, alignment irregular to regular; accessory faceting not recognized. Axials approximately equidimensional, aboral appearance unknown; in oral aspect, radial water-vascular channel enclosed, small, tubular. Axials approximately bilateral both along and perpendicular to transverse ridge; podial basin shared by sequential axials; compound axials not recognized. Mouth frame ossicles small, appearing little differentiated from more distal ossicles; mouth-angle ossicles rectangular. First virgal short, otherwise similar to more lateral virgals. Abradial virgals somewhat enlarged irregular to cylindrical, rod shaped. Any accessories unknown.</p><p>REMARKS</p><p>The differing preservational styles of Ophioxenikos and the French-Moroccan genera render comparisons difficult. Floian Ophioxenikos is younger than Tremadocian Cantabrigiaster and the Saint Chinian genera but older than Middle Ordovician Archegonaster .</p></div>	https://treatment.plazi.org/id/467887FDC3013A57FF5286F963D4FD1B	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Blake, Daniel B.;Lefebvre, Bertrand	Blake, Daniel B., Lefebvre, Bertrand (2025): The class Somasteroidea and its significance among early Asterozoa (Echinodermata). Comptes Rendus Palevol 24 (23): 449-487, DOI: 10.5852/cr-palevol2025v24a23, URL: https://doi.org/10.5852/cr-palevol2025v24a23
467887FDC3013A57FF12801B62F6FBE5.text	467887FDC3013A57FF12801B62F6FBE5.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Ophioxenikosinae Blake & Lefebvre 2025	<div><p>Subfamily OPHIOXENIKOSINAE n. subfam.</p><p>urn:lsid:zoobank.org:act: FDF53B0D-66B0-46B5-A22A-B60C7C4BB7CD</p><p>TYPE GENUS. — Ophioxenikos Blake &amp; Guensburg, 1993 .</p><p>DIAGNOSIS. — Substellate Chinianasteridae . Abactinals granular to plate-like, closely appressed. Ambital framework ossicles moderately elongate, aligned, weakly overlapping. Radial water-vascular channel small; skeletally closed. Podial basin boundary approximately medial, basin shared equally by successive axials. Adradial adaxials weakly differentiated, virgalia relatively short.</p><p>REMARKS</p><p>For purposes of comparison, the diagnosis is written in parallel with those for the Chinianasterinae and Villebrunasterinae . The Ophioxenikosinae n. subfam. is known only from O. langenheimi; the diagnosis applies at the species level.</p></div>	https://treatment.plazi.org/id/467887FDC3013A57FF12801B62F6FBE5	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Blake, Daniel B.;Lefebvre, Bertrand	Blake, Daniel B., Lefebvre, Bertrand (2025): The class Somasteroidea and its significance among early Asterozoa (Echinodermata). Comptes Rendus Palevol 24 (23): 449-487, DOI: 10.5852/cr-palevol2025v24a23, URL: https://doi.org/10.5852/cr-palevol2025v24a23
467887FDC3013A54FC63875E65BEF846.text	467887FDC3013A54FC63875E65BEF846.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Archegonaster pentagonus Spencer 1951	<div><p>Archegonaster pentagonus Spencer, 1951</p><p>Archegonaster pentagonus Spencer, 1951: 101, pl. 2, fig. 34; pl. 3, figs 37, 38; pl. 4, figs 39, 40; text-figs 9, 10, 12-15. — Ubaghs 1953: fig. 18. — Fell 1963c: 463, fig. 5I. — Spencer &amp; Wright 1966: 41, fig. 39.3. — Smith &amp; Jell 1990): 753, fig. 37-51. — Dean Shackleton 2005: 64, pl. 3.2, fig. 12a. — Blake &amp; Guensburg 2015: 477, fig. 4.2. — Villier et al. 2018: 404.</p><p>TYPE MATERIAL. — Holotype. Czech Republic • 1 specimen; Prague Basin, Osek; Šárka Formation, Darriwilian (Middle Ordovician); NMP L10143 (part) and NMP L10144 (counterpart).</p><p>REFERRED SPECIMENS. — Reviewed from the literature (see Smith &amp; Jell 1990; Dean Shackleton 2005).</p><p>TYPE LOCALITY AND HORIZON. — Šarká Formation (Llanvirn), close to Ošek, Prague Basin, Czech Republic.</p><p>DESCRIPTION</p><p>Somasteroid in life low-arched, outline pentagonal. Aboral skeleton limited to granules. Madreporite aboral, surface of radiating ridges and grooves. Ambital framework well-defined, marginals robust. Axials “T”-shaped, overlapping, with a large opening, an apparent podial pore. First adaxials strongly differentiated, more lateral adaxials proportionately small, rod-like. Proximal virgalia not recognized.</p><p>REMARKS</p><p>The Jaekel (1923) treatment of Archegonaster was cursory, the specific name later designated from a Jaekel manuscript (Spencer 1951: 101). Morphology was reviewed in detail by Spencer (1951), Smith &amp; Jell (1990), and Dean Shackleton (2005).</p></div>	https://treatment.plazi.org/id/467887FDC3013A54FC63875E65BEF846	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Blake, Daniel B.;Lefebvre, Bertrand	Blake, Daniel B., Lefebvre, Bertrand (2025): The class Somasteroidea and its significance among early Asterozoa (Echinodermata). Comptes Rendus Palevol 24 (23): 449-487, DOI: 10.5852/cr-palevol2025v24a23, URL: https://doi.org/10.5852/cr-palevol2025v24a23
