Prototrochus robbinsae, O’Loughlin, Mark & Macintosh, Hugh, 2015

O’Loughlin, Mark & Macintosh, Hugh, 2015, New Prototrochus species of sea cucumber from Australia (Echinodermata: Holothuroidea: Synaptida: Myriotrochidae), Zootaxa 3995 (1), pp. 264-270 : 266

Prototrochus robbinsae sp. nov.

Figs 1–3 , Table 1

Material examined. Holotype — NMV F151834 (permanent slide mount), Western Australia, Indian Ocean, Albany region, T6 700, 35.383889ºS 118.316111ºE, collected by grab, 772 m, CSIRO cruise Southern Surveyor SS07/2005 stn. 180, 9 August 2005.

Description. Prototrochid species, incomplete specimen (anterior parts only), diameter of calcareous ring 0.65 mm long (preserved). Tentacles lack ossicles. Body wall with numerous myriotrochid wheels; rims rounded; diameters of wheels 114–128 µ m; wheel hub diameters 22–31 µ m; spokes nine; teeth 27–34.

Distribution. Western Australia, Indian Ocean, continental slope off Albany, 35.38ºS, 118.32ºE, 772 m.

Etymology. Named robbinsae for Roni Robbins, with appreciation of her dedicated and productive partnership with Roger Bamber as ARTOO Marine Biology Consultants.

Remarks. Prototrochus robbinsae sp. nov. is distinguished in the key from the other five Australasian species of Prototrochus .

Figures

FIGURE 1. Prototrochus roniae sp. nov. holotype part-specimen (SAMA K 4516). A, photo of anterior end; scale bar 100 µ m. Prototrochus robbinsae sp. nov. holotype part-specimen (NMV F 151834). B, photo of anterior end showing part of calcareous ring and three tentacles; arrow indicates groove for nerve penetrating radial plate; scale bar 100 µ m long; C, enlarged view of tentacle illustrating lobed margin of tentacle and absence of tentacle ossicles.

FIGURE 2. Photos of wheels from the Australian slope species of Prototrochus Beljaev & Mironov, 1982; scale bars each 50 µ m long). A, Prototrochus roniae sp. nov. holotype (SAMA K 4516); B, outline of parameters of wheel in A; C, Prototrochus robbinsae sp. nov. holotype (NMV F 151834); D, Prototrochus burni O’Loughlin (in O’Loughlin & VandenSpiegel, 2007) holotype (NMV F 94697); E, Prototrochus staplesi O’Loughlin (in O’Loughlin & VandenSpiegel, 2007) holotype (NMVF 94698); F, Prototrochus taniae O’Loughlin (in O’Loughlin & VandenSpiegel, 2007) holotype (NMV F 59591).

FIGURE 3. Geographical and depth distribution of Australasian species of Prototrochus Beljaev & Mironov, 1982.