Psolus springthorpei, Mackenzie, Melanie & Whitfield, Emily, 2011

Mackenzie, Melanie & Whitfield, Emily, 2011, An overview of the Australian psolid sea cucumbers (Echinodermata: Holothuroidea: Psolidae) with the description of 5 new species, Zootaxa 3037, pp. 21-36 : 31-32

Psolus springthorpei sp. nov.

Table 1 , Figures 6 a–f.

Material examined. Holotype. Queensland, North East of Sandy Cape, 24º28'12''S 153º31'12''E, rock, coarse sand and shell, 1330–1380 m, HMAS Kimbla stn 17, P.H. Colman, G. Hangay and S.J. Keable, 8 Jul 1984, AM J23014 . Paratype. Type locality, depth and collection date, AM J24095 (1).

Description. Psolus species up to 28 mm long, 17 mm wide and 5 mm high (holotype, preserved); elongate, oval form with very low profile, slightly elevated oral and anal cones; 5 large oral scales interspersed with smaller digitiform scales, all pointed apically, and smaller encroaching scales at base, no clear demarcation between body wall scales and oral scales, discrete anal cone with very small scales up to 1 mm long; tentacles 10, 8 large, 2 small ventrally; dorso-lateral scales up to 5 mm long and smooth microscopically, ventral margin scales small, 1–3 mm long, sole bare mid-ventrally, surrounded by an inner series (zig-zag to double-row) of larger tube feet separated by ribbed skirting from a peripheral single series of distinctly smaller tube feet.

Large multi-layered dorso-lateral ossicles (scales) up to 2.24 mm long, with rare thick, smooth, perforated plates (broken, up to 256 µ m). Sole ossicles irregular smooth plates with occasional knobbed margins, typically 130–180 µ m long, with 2 or more round to oval perforations.

Colour (preserved). Uneven brown to dark brown dorsally, white translucent sole.

Distribution. Australia, Queensland, NE of Sandy Cape; 1330–1380 m.

Etymology. Named for Roger Springthorpe (Marine Invertebrate Section, Division of Invertebrate Zoology, Australian Museum), with appreciation of his gracious assistance with loan material and data for this research.

Remarks. Psolus springthorpei sp. nov. is distinguished morphologically from other Australian Psolus species by a combination of: microscopically smooth dorso-lateral scales, flattened profile with slightly elevated oral and anal cones, smaller digitiform oral scales between the 5 larger and more regular scales, and uneven brown colouration on dorsal scales.

Figures

FIGURE 6. Psolus springthorpei sp. nov. holotype (a – f, AM J 23014): a, dorsal view; b, lateral view; c, ventral view; d, sole ossicle; e, dorsal ossicle, fragment of perforated plate; f, dorsal ossicle, fragment of multi-layered ossicle (scale).