Oligobregma mucronata Blake, 2015, new species

• Main Author: Blake, James A.
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2015
• Subjects: Biodiversity; Taxonomy; Animalia; Annelida; Polychaeta; Scalibregmatidae; Oligobregma; Oligobregma mucronata; Antarc*; Antarctic; Antarctic Peninsula; Ice Shelf; Larsen Ice Shelf
• Online Access: https://doi.org/10.5281/zenodo.6102463; http://treatment.plazi.org/id/038D87CDFFA1BC0EFF16FC23FBB6FD54

Oligobregma mucronata new species Figures 8‒9 Material examined . East Antarctic Peninsula, RVIB Nathaniel B. Palmer Cruise 2000-03, Collector, J.A. Blake.— Larsen-A Ice Shelf Area, Greenpeace Trough : Sta. NBP-06, 733 m, 2 specimens poorly preserved (JAB); Sta. NBP-07A, 839 m, 3 paratypes (2 complete, LACM-AHF Poly 7011); Sta. NBP-07B, 839 m, 1 specimen (JAB); Sta. NBP- 16, 713 m, 5 specimens (1 adult, 4 juveniles) (JAB); Sta. NBP- 17, 719 m, 1 juvenile (JAB); Sta. NBP- 18, 665 m, 3 paratypes, 1 adult, 2 juveniles (AHF-Poly 7012); Sta. NBP- 19, 879 m, 1 specimen (JAB); Sta. NBP- 20, 899 m, 7 paratypes (USNM 1281914); Sta. NBP- 21, 912 m, holotype and 4 paratypes (LACM-AHF Poly 7013, 7014); Sta. NBP- 22, 868 m, 4 specimens (JAB).— LIS-A Area, transect along border with Larsen Ice Shelf B: Sta. NBP- 13, 323 m, 1 specimen (JAB). Description . Holotype incomplete, 16 mm long, 3.5 mm wide for 30 setigerous segments; two complete paratypes from Sta. NBP-21, one 11 mm long, 1.4 mm wide with 27 setigerous segments; second 9.5 mm long, 1.5 mm wide with 28 setigerous segments. Body expanded through first eight setigers, thereafter narrowing to posterior end. Color in alcohol light pink, without body pigment. Body segments with transverse rows of weakly raised pads; setigers 1‒3 uniannulate to biannulate (Fig. 8 A‒B); setigers 4 and subsequent segments becoming quadriannulate with low inconspicuous pads throughout (Fig. 9 A). Venter with prominent ventral midline from setiger 2 composed of a row of large pads within a groove (Fig. 8 B); each segment with at least two pads, each subdivided at middle by transverse groove, forming four structures per segment, corresponding to quadriannulate rows of segmental pads (Fig. 9 A). Branchiae absent. Pygidium of holotype with indistinct lobes, with two cirri present; paratypes with up to four anal cirri (Fig. 8 F). Prostomium broadly curved across anterior margin, weakly expanded laterally, narrowing posteriorly; with two short, rounded lobes emerging subapically from anterior ...