Caudacalanus mirus Markhaseva & Schulz, 2008, sp. nov.

• Main Authors: Markhaseva, Elena L., Schulz, Knud
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2008
• Subjects: Biodiversity; Taxonomy; Animalia; Arthropoda; Maxillopoda; Calanoida; Arctokonstantinidae; Caudacalanus; Caudacalanus mirus; Southern Ocean
• Online Access: https://doi.org/10.5281/zenodo.6227774; http://treatment.plazi.org/id/EB55880CFFE7FFFFFF4B0310FD48A006

Caudacalanus mirus sp. nov. (Figs 1–3) Holotype. Dissected adult female (ZMH Reg. no. K–41255), body length 2.70 mm. Collected Southern Ocean, 60º38’S 53º57’W, RV Polarstern (ANDEEP I), 30 January 2002, above the seabed at 2893– 2889 m. Paratype . Dissected adult female (ZMH Reg. no. K–41256), body length 2.80 mm. Collected Southern Ocean, 65º19’S 51º31’W, RV Polarstern (ANDEEP II), 0 5 March 2002, above the seabed at 3050 m. The holotype and paratype are deposited at the Zoological Museum Hamburg, University of Hamburg (ZMH). Description. Female: total length 2.70–2.80 mm (n=2). Prosome 1.3–1.5 times as long as urosome. Rostrum as an elongated cone (Fig. 1 C–D). Posterior corners of prosome as short rounded lobes (Fig. 1 A–B, I). Genital double somite symmetrical (Fig. 1 H–I, K). Caudal rami asymmetrical; right ramus nearly twice as long and wide as left; both rami with 4 terminal setae; right ramus with a small mediodorsal seta, ventral seta lacking; left ramus with a small medioventral seta, dorsal seta lacking (Fig. 1 B, F–G). Antennule extending to posterior border of prosome somite 3 (Fig. 3 A–D), 25­segmented, segments 24– 25 incompletely separate, armature as follows: I–1 s, II– IV–6 s + 1ae, V–2 s, VI–2 s, VII–2 s + 1ae, VIII–2 s, IX– 2 s, X– XI–4 s + 1ae, XII–1 s, XIII–2s, XIV–2s, XV–1s, XVI–2s, XVII–1s, XVIII–1s, XIX–1s, XX–1s, XXI– 2s, XXII– 1s, XXIII–1s, XXIV–2s, XXV–2s, XXVI–2s, XXVII–2s, XXVIII–3s+ 1ae. Antenna (Fig. 2 A), coxa with 1 seta; basis with 2 setae; first endopodal segment with 1 seta (2 in paratype), second with 7 (8 in paratype) and 6 setae (13­14 setae in total), endopod about 1.8 times as long as exopod; exopod 8­segmented with 0, 1, 1, 1, 1, 1, 1 and 3 setae, second segment complex of 3 ancestral segments with 0–0–1 setae. Mandible (Fig. 2 B–C), gnathobase with 4 large teeth and seta; basis with 2 setae; endopod segment 1 without setae, segment 2 with 8 setae; exopod 5­segmented with 1, 1, 1, 1 and 2 setae. Maxillule (Fig. 2 D), praecoxal arthrite with 7 terminal spines (8 spines ...