taxonID	type	description	language	source
03FD212EC1140C7BFF294C7EFC46F974.taxon	discussion	Remarks: See emended diagnosis in Messing (2016).	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC1140C7BFF294C7EFC46F974.taxon	biology_ecology	Stratigraphical distribution: Eocene – Recent (see Merle & Roux 2018).	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC1140C7CFF294D43FD72FEA9.taxon	type_taxon	Type species of the genus: Porphyrocrinus verrucosus Gislén, 1925.	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC1140C7CFF294D43FD72FEA9.taxon	biology_ecology	Stratigraphical distribution: late Miocene – Recent.	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC1140C7CFF294D43FD72FEA9.taxon	diagnosis	Emended diagnosis: Crown usually of five rays, exceptionally up to 17 rays; arms usually undivided or with axillaries beyond IBr 7, arm pattern of consecutive brachial pairs (rarely triplets) or alternating brachial pairs and free brachials, trifascial ligamentary articulation uniting two brachials of a pair, usually Br 7 to 9 bearing first pinnule; aboral cup at least slightly conical, usually taller than wide, basals conspicuous never fused, usually pentagonal; proxistele well-differentiated with very variable number of discoidal columnals frequently united by syzygies of pentalobate facets; mesistele columnals of synarthries moderately oval, variable number of cryptosynarthries or ankylosed synarthries in distal mesistele or dististele.	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC1130C7FFF294B2AFC0BFC35.taxon	description	Figs. 3 and 4 A – B, D – E, G – H, Tabls. 3 – 4	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC1130C7FFF294B2AFC0BFC35.taxon	materials_examined	Material examined: 10 columnals (included 4 figured), 18 brachials (included 3 figured).	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC1130C7FFF294B2AFC0BFC35.taxon	diagnosis	Emended diagnosis: distal stalk with smooth columnals, synarthries with stout fulcral ridge of wide dense calcite axis and up to seven consecutive cryptosynarthries of radiating syzygial outer crenularium; aboral cup approximately cylindrical, but slightly constricted medially	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC1130C7FFF294B2AFC0BFC35.taxon	description	Description: Quantitative columnal characters given in Table 3. Three columnals 1.5 times taller (H) than wide (D) belonging to mid mesistele (Fig. 3 A), with diameter at mid-height (1.12 mm) smaller than that of articular facets perpendicular to fulcral ridge (d 1.15 mm), synarthries slightly oval (D / d 101) with massive triangular fulcral ridge segments allowing only a very small range of movement. Three other columnals attributable to the dististele-mesistele transition, almost as high as wide with marked ellipticity of synarthries (Fig. 3 B – D) allowing stalk flexibility, robust fulcral ridge with more elongated segments and a broad axis of dense calcite (Fig. 3 D). Other columnals of variable shape with distinctly less elliptical synarthries (D / d <1.15) belonging to the dististele; including a largest one wider than high, widening towards distal facet, with proximal facet having a marked ligament pit restricted to center and evoking an articulation in the process of ankylosis (Fig. 3 – E) probably corresponding to a columnal preceding attachment disc. Arms mainly made up of brachial pairs, each composed of two brachials joined by trifascial ligamentary articulation (Fig. 4 A – B), distal brachial bearing one pinnule, except for a few free brachials (2 %) with only muscular synarthries; no axillary observed. Quantitative characters of brachials examined here are given in Table 4. Diameter varying from> 1 up to 1.70 mm; thickness (H / D) varying according to brachial type and its position along arm; free brachials the thickest (> 0.72) and proximal brachial of a pair the least thick (<0.56), thickness tending to decrease from distal to proximal arm in Porphyrocrinus. Ligamentary articulation uniting two brachials of a pair with a fulcral ridge separating two lateral ligament depressions and forming a more or less open V framing deep aboral fossa (Fig. 4 A – B). Muscular synarthries having a straight-line fulcral ridge, aboral ligament areas wide and deep, boundary between internal ligament and muscle areas indistinct (Fig. 4 D – E). Pinnule socket subcircular and relatively wide (0.4 times brachial diameter) (Fig. 4 D – G). External surface covered by broken spines (Fig. 4 E, H).	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC1130C7FFF294B2AFC0BFC35.taxon	discussion	Remarks: The genus Porphyrocrinus is known from all oceans except the eastern Pacific (Roux et al. 2002; Eléaume et al. 2012; Messing 2007, 2016). P. polyarthra is the single phrynocrinid species described from the Indian Ocean. Two specimens without arms and a few arm fragments were collected at a depth of 400 m on the South-west Indian Ocean submarine ridge about half-way between South Africa and Amsterdam Island. The species name corresponds to the presence of successive cryptosynarthries in the distal stalk (A. M. Clark, 1973, fig. 6 a, g). Very similar cryptosynarthries with conspicuous radial syzygial crenularium were also observed in the two Atlantic species P. thalassae and P. daniellalevyae (Roux 1977; Messing 2016). Messing (2007) considered that P. polyarthra was a junior synonym the western tropical Pacific P. verrucosus. However, such cryptosynarthry with radiating syzygial crenularium is absent in the distal stalk of western Pacific Porphyrocrinus specimens and the synonymy verrucosus / polyarthra remains questionable. Our Plio-Pleistocene brachials and columnals share with the extant Atlantic species P. thalassae and P. daniellalevyae the same trifascial brachial articulations (Fig. 2 C), large pinnule socket (Fig. 2 F), spiny external ornamentation (Fig. 2 I), and distal columnal of smooth external surface with robust fulcral ridges. Unfortunately, stalk cryptosynarthries were not observed because the Rodrigues material includes only a few distal columnals. Eléaume et al. (2014, fig. 1 c) published a view of a distal columnal synarthry belonging to a specimen from the southern Indian Ocean attributed to P. polyarthra. This specimen differs from the Rodrigues specimens in having (1) brachials with a smooth outer surface without spines, (2) distal columnals with their outer surface punctuated by irregular depressions, and more elliptical synarthries showing a thinner fulcral ridge whose axis is marked by a distinctly narrower axe of dense calcite, and (3) synarthries of the mesistele with larger and deeper ligament fossae. It could therefore belong to P. verrucosus rather than P. polyarthra. In the present state of knowledge, it seems that two species of Porphyrocrinus occur in the Indian Ocean, one attributable to P. verrucosus in agreement with Roux et al. (2019, fig. 4 E), the other corresponding to P. polyarthra to which the ossicles collected off Rodrigues Island belong.	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC1130C7FFF294B2AFC0BFC35.taxon	distribution	Occurrence: Indian Ocean, about half-way between South Africa and Amsterdam Island to the east at a depth of 400 m (extant specimens) and off Rodrigues Island, on the western Rodrigues Ridge, with the biotope not clearly determined but at a depth shallower than 1460 m (Plio-Pleistocene).	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC1100C7FFF294EE4FD41FA92.taxon	type_taxon	Type species of the genus: Conocrinus cherbonnieri Roux, 1976.	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC1100C7FFF294EE4FD41FA92.taxon	biology_ecology	Stratigraphical distribution: Paleocene – Recent.	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC1100C7FFF294996FC32FBED.taxon	discussion	Remarks: see emended diagnosis in Roux et al. 2019.	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC1100C7FFF294996FC32FBED.taxon	biology_ecology	Stratigraphical distribution: late Cretaceous (Campanian) – Recent.	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC1100C70FF294F33FE87FF61.taxon	description	Fig. 5 F – G	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC1100C70FF294F33FE87FF61.taxon	materials_examined	Type material: a single aboral cup (holotype OPH 206).	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC1100C70FF294F33FE87FF61.taxon	etymology	Etymology: from sediment dated to the Pliocene.	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC1100C70FF294F33FE87FF61.taxon	diagnosis	Diagnosis: as the description of the holotype. Arms and stalk unknown.	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC1100C70FF294F33FE87FF61.taxon	distribution	Type locality: Mascarene Plateau, to the east and west of the island of Rodrigues, Indian Ocean.	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC1100C70FF294F33FE87FF61.taxon	description	Description of the holotype: Elongate aboral cup with lower half inverted conical and upper half subcylindrical (Fig. 5 F), basals fused, discrete suture between radials, height (H) 1.90 mm, (D) maximum diameter 0.85 mm, H / D 2.23, diameter of radial ring 0.81 mm, aboral diameter (Dp) 0.40 mm, Dp / D 0.47; adoral face with moderate central depression at bottom of which lumen of axial canal obscured by stereomic plug, discrete adoral radial grooves, ratio central depression to radial ring diameter 0.59; distal synarthry of radials with deep muscular areas, aboral ligament area restricted to outer margin and very prominent interradial ridges on inner side (Fig. 5 G).	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC1100C70FF294F33FE87FF61.taxon	discussion	Remarks: The good preservation of the adoral face morphology allows us to see that Cherbonniericrinus pliocenicus n. sp. displays characters identical to those of the type species of the genus (Fig. 3 H) as described by Roux et al. (2019). C. cherbonnieri differs in having a slightly greater cup size (H 2.2 mm, D 1.50 mm) a regular inverted conical shape moderately elongated (H / D 1.47) with sides slightly convex, and a smaller adoral diameter (Dp / D 0.40) (Roux 1976).	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC1100C70FF294F33FE87FF61.taxon	biology_ecology	Occurrence: Indian Ocean, western Rodrigues Ridge at a depth of 1460 m (biotope possibly shallower). PlioPleistocene.	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC11F0C70FF294C21FCF9F95F.taxon	type_taxon	Type species of the genus: Eugeniacrinus pyriformis Münster in Goldfuss, 1826.	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC11F0C70FF294C21FCF9F95F.taxon	biology_ecology	Stratigraphical distribution: early Eocene – Plio-Pleistocene.	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC11F0C71FF294D79FACBFB50.taxon	description	Fig. 5 A – E	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC11F0C71FF294D79FACBFB50.taxon	materials_examined	Type material: 6 aboral cups (holotype OPH 207, 1 figured paratype OPH 208, 4 paratypes OPH 209 not figured).	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC11F0C71FF294D79FACBFB50.taxon	etymology	Etymology: from sediment off the island of Rodrigues, western Rodrigues Ridge.	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC11F0C71FF294D79FACBFB50.taxon	diagnosis	Diagnosis: species with aboral cup regularly inverted conical of height usually slightly greater than diameter (Hc / Dc 1.03 to 1.31), diameter lesser than 0.75 mm, basals slightly higher than radials and ratio central adoral depression to radial ring diameter 0.47 to 0.55. Arm and stalk unknown.	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC11F0C71FF294D79FACBFB50.taxon	distribution	Type locality: Mascarene Plateau, western Rodrigues Ridge, Indian Ocean.	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC11F0C71FF294D79FACBFB50.taxon	description	Description of the type series: Aboral cup height (Hc) up to 0.80 mm and diameter (Dc) up to 0.72 mm, ratio Hc / Dc varying from 1.03 to 1.31 independently to growth (Table 5), ratio adoral to maximum diameter (Dp / Dc) 0.30 – 0.35. Like the holotype, all cups inverted conical, basals indistinct (Fig. 5 D) sometimes underlined by discreet sutures (Fig. 5 A), basals slightly higher than radials, coarse interradial adoral ribs separating oval muscular synarthries (Fig. 5 E). Central depression of adoral face without basal plug, hemispherical in holotype (Fig. 5 C) to more flared like in paratype 1 (Fig. 5 B); ratio central depression to radial ring diameter 0.47 in holotype and 0.55 in paratype 1.	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC11F0C71FF294D79FACBFB50.taxon	discussion	Remarks: According to Roux et al. (2019), the presence of coarse interradial ribs developed up to the outer edge of adoral face excludes that these small cups are juveniles of Cherbonniericrinus pliocenicus n. sp. described above. Paraconocrinus was identified from the Eocene and the Early Miocene of southern France and northeastern Italy (Merle & Roux 2018; Roux et al. 2019; Roux & Philippe 2021). The material described herein extends its stratigraphical distribution to the Pliocene. The genus remains unknown in extant fauna. Occurrence: Indian Ocean, western Rodrigues Ridge at a depth of 1460 m (biotope possibly shallower).	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC11E0C71FF294F71FD41FA54.taxon	discussion	Remarks: Roux et al., (2019) restricted the family Bathycrinidae to Bourgueticrinina with IBr 2 ax other than Atelecrinidae.	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC11E0C71FF294F71FD41FA54.taxon	biology_ecology	Stratigraphical distribution: Paleocene – Recent.	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC11E0C71FF294C6DFCFEF938.taxon	type_taxon	Type species of the genus: Bathycrinus gracilis Thomson, 1872.	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
03FD212EC11D0C73FF294CD5FC09FF61.taxon	description	Fig. 6 F Undetermined genus and species Material examined: a single small columnal (OPH 212). Description: columnal of heptagonal facet with radiate crenulae poorly preserved (Fig. 6 F), diameter 0.75 mm, height 0.50 mm. Remarks: Heptagonal shape, or 7 crenular units on articular facets, is a frequent condition in hyocrinid columnals (Mironov & Sorokina, 1998; Roux & Lambert, 2011) but unknown in other extant stalked crinoid families. Moreover, symmetry 6 – 7 is more common in juvenile stalks and tends to disappear during growth by adjunction of new crenular units and generalization of circular articular facets. The small size of this columnal suggests that it belongs to a juvenile specimen which cannot be attributed at the genus rank.	en	Roux, Michel, Thuy, Ben, Gale, Andy S. (2025): Plio-Pleistocene deep-sea crinoid (Echinodermata) diversity from the western Rodrigues Ridge, Indian Ocean, revealed by microfossil evidence. Zootaxa 5583 (3): 509-525, DOI: 10.11646/zootaxa.5583.3.5, URL: https://doi.org/10.11646/zootaxa.5583.3.5
