Chaetozone shackletoni Blake 2018, new species

• Main Author: Blake, James A.
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2018
• Subjects: Biodiversity; Taxonomy; Animalia; Annelida; Polychaeta; Terebellida; Cirratulidae; Chaetozone; Chaetozone shackletoni; Drake Passage; Scotia Sea; South Shetland Islands; Weddell Sea
• Online Access: https://doi.org/10.5281/zenodo.3798526; http://treatment.plazi.org/id/03A2CB16FFAAA22BFF36FE2AFAECFCBB

Chaetozone shackletoni new species Figures 51 B–C, 52, 53 Material Examined. Scotia Sea, Powell Basin , R / V Polarstern , ANDEEP III (ANT-XXII/3), Sta. PS67/121-10, 14 Mar 2002, 63°41.74ʹS, 50°42.99ʹW, box corer, 2621 m, holotype (SMF 24934) and 2 paratypes with fragments (SMF 24935).— Drake Passage, off South Shetland Islands , R / V Polarstern , ANDEEP I (ANT-XIX/3), Sta. PS61/105-5, 14 Feb 2002, 61°23.72ʹS, 58°50.04ʹW, box corer, 2266 m, 5 paratypes , (SMF 24936).— Weddell Sea off Cape Norvegia , R / V Polarstern , ANDEEP III (ANT-XXI/3), Sta. PS67/78-6, 21 Feb 2005, 71°09.45ʹS, 14°0.32ʹW, box corer, 2168 m, 1 paratype on SEM stub (MCZ149853); off Coats Land , USCG Glacier , S ta. 69- 19, 11 Mar 1969, 74.105°S, 32.605°W, 1622 m, 1 paratype (USNM 1490775); Sta. 69-20, 12 Mar 1969, 73.823°S, 31.682°W, 2288 m, 2 paratypes (USNM 1490776). Detached posterior ends present. Some specimens photographed alive during ANDEEP I cruise complete (Sta. PS 67/121-10) but fragmented during preservation. Description. A small to moderately-sized species; holotype mostly complete, 10.9 mm long, 0.35 mm wide across anterior setigers, 0.8 mm wide across expanded middle segments, with about 50 setigerous segments; incomplete paratype from Glacier Sta. 69-19, 9.5 mm long, 0.4 mm wide across anterior setigers, 1 mm wide across expanded middle segments, with 43 segments. Body with distinctive shape, including narrow anterior thoracic region of about 15–20 setigers, enlarged middle body “stomach” area, and narrow posterior setigers (Fig. 52A, C). Anterior and middle segments generally cylindrical in cross section, with narrow, shallow mid-dorsal groove present (Fig. 53A) or absent in anterior thoracic segments; venter of thoracic segments weakly flattened, or with shallow groove present or absent; posterior segments somewhat dorsoventrally flattened; weakly developed. Expanded middle segments prominent, with enlarged stomach area filled with fine sediment (Fig. 52A, C), also swollen with eggs in mature specimens. Color in life: deep ...