Syssitomya pourtalesiana Oliver 2012, sp. nov.

• Main Author: Oliver, P. Graham
• Format: Other/Unknown Material
• Language: unknown
• Published: 2012
• Subjects: Biodiversity; Taxonomy; Animalia; Mollusca; Bivalvia; Galeommatida; Lasaeidae; Syssitomya; Syssitomya pourtalesiana; Norwegian Sea; Norway; Rockall Trough; Grieg; Gage
• Online Access: https://zenodo.org/record/3858680; https://doi.org/10.5281/zenodo.3858680

Syssitomya pourtalesiana sp. nov. Figs 4B, E; 7, 8 A-B ? Kellia symmetros – Locard 1898: 297, pl.XIII, figs 18-20. ? Kellia symmetros – Friele & Grieg 1901: 29. Axinodon symmetros – Bouchet & Warén 1979: 216-217, fig. 3A-D. Montacuta (Axinodon) symmetros – Gage et al. 1985: 189. Not Axinodon symmetros – Warén 1980: 47. Not Axinodon symmetros – Aartsen 1996: 30, fig. 5 (is Axinodon ellipticus Verrill & Bush, 1898). Not Axinodon sp.1 – Olabarria 2005: 20 (is Mysella sp.). Etymology After Pourtalesia, the host echinoid; and the Latin termination – iana, to denote belonging with. Material examined Holotype 1 specimen, Norwegian Sea, Ormen Lange gas field, off Sør-Trøndelag, Central Norway, 63°47'N 03°35'E, 815-925 m, Swedish Museum of Natural History SMNH5566. Paratypes Same recolt data as for the holotype: 7 specimens, Swedish Museum of Natural History SMNH 5567; 1 specimen + 2 shells, National Museum Wales, Zoology- NMW. Z.2012.014. Other material 8 specimens, Rockall Trough, RRS Challenger, stn ES137, 54°40'N 12°19'W, 2900 m, 22 Feb. 1978, leg. I.J. Killeen NMW.Z. 2009.045.2; 6 specimens, Rockall Trough, RRS Challenger, stn ES231, 54°42'N 12°12'W, 2898 m, 17 May 1983, leg. I.J. Killeen, National Museum wales, Zoology- NMW.Z. 2009.045.3. Type locality Norwegian Sea, Ormen Lange gas field, off Sør-Trøndelag, Central Norway, 63°47’N 03°35’E, 815- 925 m, 2009. Swedish Museum of Natural History, det. Anders Warén. Measurements (SMNH5566 and part of SMNH5567 paratypes) Length (mm) Height (mm) L:H Holotype 4.1 3.2 1.3:1 Paratype 3.0 2.3 1.3:1 Paratype 2.4 2.0 1.2:1 Paratype 1.8 1.4 1.3:1 Paratype 1.3 1.1 1.2:1 Paratype 1.3 1.1 1.2:1 Description based on specimens from the Norwegian Sea SHELL. (Figs 7, 8) Small, largest length 4.2 mm, height 3.2 mm, breadth 2.7 mm. Thin, fragile, translucent. Equivalve. Inequilateral, beaks distinctly behind midline. Umbos moderately inflated, beaks orthogyrate or marginally prosogyrate. Outline subovate, longer than high, length to height ratio 1.3:1, distinctly expanded ...