Bythocypris polarsterni Brandão, 2008, sp. nov.

• Main Author: Brandão, Simone N.
• Format: Other/Unknown Material
• Language: unknown
• Published: 2008
• Subjects: Biodiversity; Taxonomy; Animalia; Arthropoda; Ostracoda; Podocopida; Bairdiidae; Bythocypris; Bythocypris polarsterni; Southern Ocean; Weddell Sea; Weddell
• Online Access: https://zenodo.org/record/6233668; https://doi.org/10.5281/zenodo.6233668

Bythocypris polarsterni sp. nov. (Figs. 24.N, O, R, S, V, W, 33 –35, 36.A–D) Etymology. From the RV Polarstern. Material: 4 live specimens. Holotype: 1 A F (SNB 0137), ANDEEP II, # 134 – 4 –E, ZMH K­ 41314. Paratypes: 1 (A­ 1) (SNB 0246), 2 (A­? 2) (SNB 0 383, B 0384), ANDEEP II, # 134 – 4 –S, ZMH K­ 41315. Distribution. NW Weddell Sea, Southern Ocean (Atlantic Sector), 4059.4 to 4068.7m. Measurements (Fig. 34). Holotype, LV, L 2.23mm, H 1.07mm; RV, L 2.22mm, H 1.01mm. Paratypes, LV, (A­ 1) L 1.76mm, H 0.88mm; (A­ 2) L 1.37–1.41mm, H 0.68mm. Diagnosis. Valves large; lateral outline quite rectilinear, subtrapezoidal; inequilateral, both anterior and posterior margins narrowly rounded, but anterior broader than posterior; ventral margin straight in LV and fairly straight in RV. Podomere VI of AII with 1 long articulated claw, 1 short fused (!) claw, and 1 or 2 short thin setae. Vibratory plate of MxI with 4 or 5 strahlen and 21 or 22 feathered setae. Vibratory plate of ApV with 4 strahlen plus around 8 setae. Fu with 3 small, 1 long, and 3 medium sized setae. Genital lobe sub­hemispherical with double coiled internal tube. Description. Valves large; lateral outline of both valves rectilinear, subtrapezoidal; inequilateral, both anterior and posterior margins narrowly rounded, but anterior broader than posterior; dorsal margin broadly rounded, posterodorsal and anterodorsal margins straight, but without conspicuous angles; ventral margin straight in LV and fairly straight in RV. Adductor muscle scars subdivided but bythocypridid in aspect, occupying a very small area (less than 1 / 7 of valve height). Calcified inner lamella broad. Zone of concrescence very narrow, marginal pore canals straight and short. Radial pore canals simple, with wide rim. Appendages strongly pigmented, dark brown, conspicuous even through closed valves. AI with slender thin podomeres I–II; very short podomeres IV–VII; chaetotaxy 1 (0/0), 2 (0/0), 3 (. 2 /0), 4 (. 1 /. 1), 5 (. 2 /. 2), 6 (. 3 /. 2), 7 (0/0: 3­4). Exopodite of AII with 2 ...