Prototrochus Beljaev & Mironov, 1982

O’Loughlin, Mark & Macintosh, Hugh, 2015, New Prototrochus species of sea cucumber from Australia (Echinodermata: Holothuroidea: Synaptida: Myriotrochidae), Zootaxa 3995 (1), pp. 264-270 : 265

Prototrochus Beljaev & Mironov, 1982

Diagnosis (after Gage & Billett 1986). Myriotrochid with ten tentacles; calcareous ring symmetrical, with dorsal and ventral plates subequal in size; dorso-lateral radial plates with single anterior projection; wheels with teeth distributed regularly, pointing towards center of hub; rods absent from body wall, sometime occurring in and around tentacles.

Remarks. O’Loughlin & VandenSpiegel (2007) noted that Beljaev & Mironov (1982) referred twelve species to their new genus Prototrochus . Only Prototrochus australis ( Beljaev & Mironov, 1981) was recorded near Australia, the holotype coming from south of Lord Howe I. in the northern Tasman Sea at 1500 m. Beljaev & Mironov (1981) noted that their new species Myriotrochus australis was the smallest known myriotrochid. The seven specimens that Beljaev and Mironov examined comprise two complete and five incomplete specimens, none longer than 2.8 mm. Consistent with this recognition of very small specimens of Prototrochus is the fact that all three anterior part-specimens reported in this work are less than 1.0 mm long.