Psolus byrdae O'Loughlin & Whitfield, 2010, sp. nov.

• Main Authors: O'Loughlin, Mark, Whitfield, Emily
• Format: Other/Unknown Material
• Language: unknown
• Published: 2010
• Subjects: Biodiversity; Taxonomy; Animalia; Echinodermata; Holothuroidea; Dendrochirotida; Psolidae; Psolus; Psolus byrdae; Ross Sea; Scotia Sea; Amundsen Sea; Byrd; Marie Byrd Seamount; Antarc*; Antarctica
• Online Access: https://zenodo.org/record/6196617; https://doi.org/10.5281/zenodo.6196617

Psolus byrdae sp. nov. Figures 1 a–f. Material examined. Holotype. Antarctica, Amundsen Sea, Marie Byrd Seamount, 69.2 ºS 117.5 ºW, 2214 m, BAS BIOPEARL stn BI 07–AGT– 2000, K. Linse et al., 15 Mar 2008, NMV F 168626. Paratypes. Ross Sea, Scott I. Bank, 516–595 m, USNM 1132854 (11). Other material. Scotia Sea, South Georgia, 56 º 18–23 'S 37 º04– 37 'W, 3413–3446 m, USNM 1132855 (2). Diagnosis. Psolus species up to 28 mm long, 5 mm high, 12 mm wide (holotype); elongate oval form, low vertical profile, lacking oral and anal cones; scales imbricating, macroscopically smooth, microscopically finely beaded, irregular shapes, large and small, rounded and angular, mosaic arrangement, up to 5 mm wide, small near ventral margin; lacking 5 discrete oral valves, oral scales numerous, digitiform or narrow pointed or triangular pointed; tentacles 10, 8 large, 2 small ventrally; calcareous ring with digitiform radial and interradial anterior projections, radial projections larger, concave radial and interradial posterior indentations; thin non-calcareous sole, single to zig-zag series of larger inner peripheral tube feet, widely separated from outer peripheral series of smaller tube feet, lacking mid-ventral tube feet, wide calcareous margin comprising large dorsal and small ventral plates between larger and smaller tube feet series; gonad tubules unbranched. Dorsal and lateral multilayered ossicles only. Central sole with rare irregular smooth cross-like ossicles and plates, cross branches sometimes joined distally to create small plates with up to 6 perforations, cross-like ossicles commonly 120 µ m long, perforated plates up to 208 µ m long. Margin of sole with numerous crosslike ossicles and perforated plates, up to 144 µ m long; elongate, narrow, perforated tube foot support plates, bluntly denticulate on concave margin, up to 400 µ m long; thick, irregular, rods and perforated plates, sometimes thick knobs on margin and surface, up to 320 µ m long. Largest tentacle ossicles irregularly oval and rounded triangular ...