Pseudomma antarcticum Zimmer, 1914

Wittmann, Karl J., 2024, The Mysidae (Crustacea, Mysida) of the ANDEEP I-III expeditions to the Antarctic deep sea with the description of twelve new species, establishment of four new genera and with world-wide keys to the species of Erythropinae and Mysidellinae, European Journal of Taxonomy 940, pp. 1-180 : 118-119

Pseudomma antarcticum Zimmer, 1914

Pseudomma antarcticum Zimmer, 1914: 89 , 389–390, pl. xxiii figs 10–12.

Pseudomma antarcticum – O.S. Tattersall 1955: 94 (records, Antarctic). — Ledoyer 1990: 41 (record, Weddell Sea). — Brandt et al. 1998: table 1 (biogeography). — Meland 2004: fig. 4, app. 2 (taxonomy, morphology, phylogeny). — Petryashov 2006: 1416 (bathymetric distribution). — Meland & Brattegard 2007: 54–57 , figs 7–8 (description, range extension, Iceland Basin). — San Vicente 2010: 48, fig. 37f–g (distribution, Antarctic). — Wittmann & Chevaldonné 2021: 154, 205, table 1, suppl. (distribution, sensory structures, taxonomy, in key). — Astthorsson & Brattegard 2022: 68, fig. 79 (distribution, Iceland Basin). — Mees & Meland 2024: AphiaID 226237 (accepted).

Material examined

SOUTHERN OCEAN • 1 imm. (BL = 12.4 mm); South Sandwich Trench , SE of Montagu Island, ANDEEP-II station 143-1; 58°44.69ʹ S, 25°10.27ʹ W to 58°44.49ʹ S, 25°10.47ʹ W; depth 773.9– 755.6 m; 25 Mar. 2002; EBS epinet • 1 imm. (BL = 8.0 mm); same collection data as for preceding except for occurrence in supranet • 1 imm. (BL = 12.7 mm), 2 juv.; NW Weddell Sea, ANDEEP-II station 131-3; 65°19.83ʹ S, 51°31.62ʹ W to 65°19.95ʹ S, 51°31.41ʹ W; depth 3049–3050 m; 5 Mar. 2002; EBS epinet • 1 ♀ imm. (BL = 15.8 mm), 1 imm. (BL = 11.5 mm), 8 juv.; same collection data as for preceding • 1 ♂ ad. (BL = 21.2 mm), 1 imm. (BL = 5.8 mm); same collection data as for preceding except for occurrence in supranet • 1 ♂ ad. (BL = 12.8 mm), 1 ♀ subad. (BL = 10.1 mm); NW Weddell Sea,ANDEEP-II station 133-3; 65°20.15ʹ S, 54°14.35ʹ W to 65°20.06ʹ S, 54°14.51ʹ W; depth 1122– 1119 m; 7 Mar. 2002; EBS epinet • 3 ♂♂ imm. (BL = 11.2–11.7 mm), 7 juv.;SE Weddell Sea,ANDEEP-III station 074-6; 71°18.35ʹ S, 13°57.71ʹ W to 71°18.28ʹ S, 13°57.31ʹ W; depth 1030–1040 m; 20 Feb. 2005; EBS epinet • 1 damaged juv.; same collection data as for preceding except for occurrence in supranet • 1 ♂ ad. (BL = 14.6 mm); eastern Weddell Slope , Kapp Norvegia, ANDEEP-III station078-10; 71°09.39ʹ S, 13°59.30ʹ W to 71°09.36ʹ S, 13°58.81ʹ W; depth 2156– 2147 m; 21 Feb. 2005; EBS epinet • 1 juv. (BL = 4.7 mm); Weddell Slope, entrance to Powell Basin, ANDEEP-III station 121-10; 63°37.73ʹ S, 50°38.09ʹ W to 63°37.55ʹ S, 50°38.37ʹ W; depth 2663– 2659 m; 15 Mar. 2005; EBS epinet • 1 ♂ ad. (BL = 16.3 mm), 3 imm. (BL = 9.3–9.7 mm); same collection data as for preceding except for occurrence in supranet • 1 ♂ ad. (BL = 14.3 mm); Powell Basin, ANDEEP-III station 133-2; 62°46.49ʹ S, 53°03.50ʹ W to 62°46.38ʹ S, 53°03.98ʹ W; depth 1584– 1579 m; 16 Mar. 2005; EBS epinet • 1 ♀ ad. (BL = 16.7 mm), 1 ♀ subad. (BL = 13.3 mm), 1 ♂ ad. (BL = 12.6 mm), 1 ♂ subad. (BL = 12.9 mm), 7 juv.; Powell Basin, SW continental slope of South Orkney Islands, ANDEEP-III station 150-6; 61°48.70ʹ S, 47°28.04ʹ W to 61°48.57ʹ S, 47°28.19ʹ W; depth 1996– 1993 m; 20 Mar. 2005; EBS epinet • 1 imm. (BL = 8.3 mm), 1 juv.; Powell Basin, SW continental slope of South Orkney Islands, ANDEEP-III station 151-7; 61°45.52ʹ S, 47°07.68ʹ W to 61°45.42ʹ S, 47°08.04ʹ W; depth 1182–1185 m; 21 Mar. 2005; EBS epinet • 1 damaged juv.; Drake Passage, NW of Elephant Island , ANDEEP-I station 041-3; 59°22.24ʹ S, 60°04.06ʹ W to 59°22.40ʹ S, 60°03.99ʹ W; depth 2375– 2372 m; 26 Jan. 2002; EBS supranet • 1 ♀ ad. (BL = 10.6 mm), 1 ♀ subad. (BL = 9.3 mm), 5 damaged juv.; Drake Passage, NW of Elephant Island ,ANDEEP-I station 042-2; 59°40.29ʹ S, 57°35.43ʹ W to 59°40.42ʹ S, 57°35.27ʹ W; depth 3683– 3680 m; 27 Jan. 2002; EBS epinet • 1 ♀ ad. (BL = 14.1 mm), 1 ♀ ad. (damaged, BL = 14.0 mm), 1 ♀ subad. (BL = 9.0 mm), 3 imm. (BL = 4.9, 8.0, 8.9 mm); Drake Passage, N of South Shetland Islands, ANDEEP-I station 046-7; 60°38.35ʹ S, 53°57.36ʹ W to 60°38.12ʹ S, 53°57.49ʹ W; depth 2893.6– 2893.2 m; 30 Jan. 2002; EBS epinet • 2 ♀♀ ad. (BL = 12.9, 16.5 mm), 2 damaged imm.; same collection data as for preceding except for occurrence in supranet • 1 ♀ ad. (damaged, BL = 8.8 mm), 1 juv.; same collection data as for preceding • 1 imm. (BL = 6.8 mm), 1 juv.; Drake Passage, NW of Elephant Island , ANDEEP-I station 129-2; 59°52.21ʹ S, 59°58.75ʹ W to 59°52.15ʹ S, 59°59.03ʹ W; depth 3643– 3622 m; 23 Feb. 2002; EBS epinet • 2 imm. (BL = 7.3, 7.8 mm) in separate vial, same collection data as for preceding • 1 imm. (BL = 11.5 mm); Bellingshausen Sea, NW of Anvers Island , ANDEEP-III station 154-9; 62°31.47ʹ S, 64°39.45ʹ W to 62°31.36ʹ S, 64°39.25ʹ W; depth 3804–3808 m; 30 Mar. 2005; EBS epinet .

Type locality and distribution

The type locality by monotypy is 65°15ʹ S, 80°00ʹ E, 3425 m ( Zimmer 1914). So far recorded from the Southern Ocean: East Antarctica, Kerguelen Island, South Georgia, South Shetlands, Clarence Island, Antarctic Peninsula and Weddell Sea, 61– 80° S, 80° E westward to 63° W, 278–3425 m ( Zimmer 1914; O.S. Tattersall 1955; Ledoyer 1990; San Vicente 2010); and from the N Atlantic: Iceland Basin, 62– 63° N, 15– 18° W, 1085–2270 m ( Meland & Brattegard 2007; Astthorsson & Brattegard 2022). All ANDEEP materials are from the Southern Ocean: South Sandwich Trench, Weddell Sea, Powell Basin, Drake Passage and Bellingshausen Sea, 59° S – 71° S, 14° W – 65° W, 756–3808 m. These records extend the known ranges in the Southern Ocean only marginally northward to 59° S, westward to 65° W, and down to 3808 m.

Remarks

Eye rudiments mesially fused except for a short disto-median cleft. Median eye-cyst leads to this cleft. Eye without ocular papilla, no visual elements, no organ of Bellonci. Basal segment of antennular trunk dorsally with antennular bursa. Terminal segment without female lobe. This segment with disto-median lobe armed with four teeth increasing in size laterally and, out of this series, an additional 0–1 short tooth positioned mesially; lobe disto-laterally with four barbed setae. Telson with bare lateral margins.