Zatsepinia antarctica Schüller & Jirkov, 2013, n.sp.

• Main Authors: Schüller, Myriam, Jirkov, Igor A.
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2013
• Subjects: Biodiversity; Taxonomy; Animalia; Annelida; Polychaeta; Terebellida; Ampharetidae; Zatsepinia; Zatsepinia antarctica; Antarc*; Antarctica; Weddell Sea
• Online Access: https://doi.org/10.5281/zenodo.6152282; http://treatment.plazi.org/id/20155B09EF04BF44FF17FBF3FB48DDEC

Zatsepinia antarctica n.sp. Figs 18–19 Holotype: ANDEEP III—st 81-8, EBS, 70°31.08'S – 70°32.23'S, 14°34.82'W – 14°34.90'W, eastern Weddell Sea, 4419 m [ZMH-26090]. Paratypes: ANDEEP III—st 80-9, EBS, 70°38.45'S – 70°39.18'S, 14°42.86'W – 14°43.43'W, eastern Weddell Sea, 3138 m (1 specimen, incomplete), ANDEEP III—st 81-8, EBS, 70°31.08'S – 70°32.23'S, 14°34.82'W – 14°34.90'W, eastern Weddell Sea, 4419 m (7 specimens, 1 x SEM, 3 complete) [ZMH-26091–26093]. Diagnosis: The species can be recognized by the dorsal shift of the last two thoracic notopodia, grooved and smooth buccal tentacles, 23–24 AUs, as well as a large pair of anal papillae. Description: Holotype 5 mm long and 0.7 wide, with 24 AUs, complete. Complete paratypes and additional specimens 4–10 mm long and about 0.5 mm wide, with 23–24 AUs (Fig. 18 A). Colour in ethanol white. One specimen ovigerous, eggs spread throughout body cavity, most concentrated in posterior segments. Prostomium simple, without lobes or glandular ridges (Figs 18 B, 18C, 19A). Nuchal organs present in posterior crest of prostomium (Fig. 19 B). Eyes absent. With [up to ten] thick, smooth and longitudinally grooved buccal tentacles, much thicker and some longer than branchiae (Fig. 18 A). Two pairs of branchiae in a transverse row, not separated by gap (Figs 18 B, 19A). Innermost branchiae connected to ТS-3, outermost to ТS-2. Branchiae smooth, with a dorsal longitudinal groove (Fig. 19 C). Outermost pair about half length of innermost pair. TS-2 without rudimentary notopodia. Paleae absent. 12 TCs, from TS-4. Notopodia of TC-1 smaller than subsequent ones and positioned somewhat dorsally. Notochaetae arranged in two rows with chaetae of anterior row about half length of posterior row, broadly winged in distal half, medially keeled (Fig. 19 C, D). 10 TUs present from TS-6. Neuropodia large, cushion-like tori. [Thoracic uncini with dental formula: MF-2-2-1-∞.] Notopodia of 2nd to last and last TCs shifted dorsally, dorsally connected by a ridge (Fig. 18 D). 24 AUs [23–24], from ...