Laevocnus leachmani Davey and O’Loughlin, 2014

O’Loughlin, P. Mark, Mackenzie, Melanie, Paulay, Gustav & VandenSpiegel, Didier, 2014, Four new species and a new genus of Antarctic sea cucumbers with taxonomic reviews of Cladodactyla, Pseudocnus, Paracucumidae and Parathyonidium (Echinodermata: Holothuroidea: Dendrochirotida), Memoirs of Museum Victoria 72, pp. 31-61 : 48-50

Laevocnus leachmani Davey and O’Loughlin sp. nov.

Zoobank LSID. http://zoobank.org:act:DD44CDAF-F84B-4D6F-

B979-FCB0EBD60015

Key 1; figures 9, 11

Pseudocnus species (Ross Sea) O’Loughlin et al., 2010: table 1.

Material examined. Holotype. Eastern Antarctica, Ross Sea , 72.08°S 175.55°E, 1620 m, stn TAN0802/139, N. Davey, 22 Feb 2008, NIWA 42203 ( UF tissue sequence code MOL N 182 ).

Paratype. Type locality and date, NIWA 61890 (1).

Other material. Ross Sea, 72.07°S 175.59°E, 1629–1645 m, stn TAN0802/135, 22 Feb 2008, NIWA 61100 (4 juvenile specimens); off George V Land, 66.57°S 142.00°E, 299–521 m, CEAMARC RSV Aurora Australis Voyage 3, stn 9EV117, 26 Dec 2007, NMV F189887 (1).

Description. Body up to 15 mm long (preserved, tentacles withdrawn), 6 mm diameter; body fusiform; body wall thin, calcareous, with a rugose surface created by a close cover of projecting spinous ossicle ends; 10 equal dendritic tentacles; 5 oral papillae, 5 anal papillae, lacking anal scales; tube feet projecting, not withdrawn, about 0.4 mm in diameter, restricted to a single, well-spaced series in all radii, extending across the introvert; calcareous ring distinct, calcified, cucumariid-like, lacking posterior prolongations; single polian vesicle; two tufts of unbranched gonad tubules; 3 embryos in withdrawn oral cavity in one specimen.

Body wall ossicles irregularly oval to oblong, single-layered, perforated, knobbed plates, with one end of plate always sharply spinous and frequently narrowed into a short distally-spinous neck, spinous apex frequently upturned, plate perforations smaller at ends, sometimes with two large perforations centrally separated by a narrow knobbed bridge, plates up to 280 µm long; lacking knobbed buttons. Tentacle ossicles perforated plates of variable form and size, up to 240 µm long, marginally spinous, sometimes with surface knobs or spines; no rods or rosettes. Tube feet endplate support ossicles bent and curved plates with apically spinous mid-plate projection.

Colour (preserved). White.

COI DNA barcode of holotype: TAACTGATTAATACCTT- TAATGATTGGAGCCCCTGACATGGCTTTCCCAC- GAATGAACAATATGAGATTCTGATTAATACCCC- CATCCTTTCTTTTACTACTAGCTTCTGCTAGTGTA- GAAAGAGGTGCAGGAACAGGATGAACTATTTACC- CCCCCTTATCTAGAAAAATAGCCCATGCAGGAG- GATC TGTAGATC TAG C TAT T T T T TCAC T TCAC- CTAGCAGGTGCCTCTTCAATTCTTGCAGC- TATAAAATTTATAACTACTATAATAAAAATGCGAG- CACCAGGTATTTATTTTGACCGTCTATCATTATT- TAT C T GAT C C GT C T T TAT TAC T G C T T T T C TAT- TACTCTTAAGTCTTCCAGTATTAGCAGGTGCTATTA- CAATGTTATTAACAGATCGAAACATAAACACTAC- CTTCTTTGATCCATCAGGTGGAGGAGATCCTATAT- TATTCCAACACTTATTCTGATTTTTTGGACACCCA- GAAGTATATATTCTTATTTTACCAGGATTTGGTAT- GATATCTCATGTA AT TACACAT TATAGAG GA A- GACAAGAACCCTTTGGATATTTAGGTATGGTTTAT- GCTATGATATCTATAGGTATTTTAGGTTTCCTAG- TATGAGCTCACCACATGTTTACTGTAGGA

Distribution. Eastern Antarctica, Ross Sea and off George V Land, 299–1645 m.

Etymology. Named for Andrew Leachman, skipper of the RV Tangaroa for 38 years, that included seven marine research voyages to Antarctica.

Remarks. Laevigatus leachmani is distinguished from other species of Laevocnus by the morphological characters detailed in the key above, as well as by>17% pair-wise K2P divergence in CO1 sequence. This species is listed as Pseudocnus species (Ross Sea) by O’Loughlin et al. (2010) ( Table 1).