Leitoscoloplos nasus Blake, 2017, new species

• Main Author: Blake, James A.
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2017
• Subjects: Biodiversity; Taxonomy; Animalia; Annelida; Polychaeta; Orbiniidae; Leitoscoloplos; Leitoscoloplos nasus; Antarc*; Antarctic; Antarctic Peninsula
• Online Access: https://doi.org/10.5281/zenodo.4901757; http://treatment.plazi.org/id/8F2387DD060A092CFF31FAD7FD0BFDFC

Leitoscoloplos nasus new species Figure 14 Material examined. Antarctic Peninsula, Eltanin Station 6-439, 0 9 Jan 1963, 63.83°S, 62.60°W, 128–165 m, holotype and 3 paratypes , USNM 1407121–2). Description. All specimens posteriorly incomplete; holotype 8.7 mm long, 0.6 mm wide, for 37 segments; largest paratype 8.3 mm long, 0.35 mm wide for 33 segments. Body rounded in cross section, with thoracic region slightly inflated. Thorax with 9–10 setigers, with each segment wider than long (Fig. 14 A–B). Transition from thorax abrupt, denoted by reduction in number of neurosetae and change in form of neuropodial postsetal lobes. Abdominal segments narrow at first, then becoming elongate, nearly twice as long as wide with parapodia at posterior end of each elongated segment (Fig. 14 C). Color in alcohol: brown. Prostomium elongate, more than twice as long as wide; tapering anteriorly to narrow, rounded tip, sometimes curved dorsally; eyespots absent; with paired nuchal organs. Peristomium short asetigerous ring, together with prostomium forming unusually elongate “head” (Fig. 14 A–B) Thoracic notopodia short, papillate on setiger 1 and sometimes setiger 2, then becoming long, fingerlike over remaining thoracic setigers; abdominal notopodia elongate, becoming narrow more posteriorly (Fig. 14 C–D). Thoracic neuropodia similar to notopodial lamellae, but overall shorter and more triangular. Abdominal neuropodia, short, thickened basally, notched distally; with subpodial flange (Fig. 14 D). Thoracic setae all long crenulated capillaries. Abdominal notopodia with 6–8 crenulated capillaries and 1–2 furcate setae; furcate setae with thin needles forming web between subequal tynes; barbs on shaft not apparent in light microscopy (Fig. 14 E). Abdominal neuropodia with 2–3 thin, non-crenulated capillaries (Fig. 14 D). Branchiae from setiger 13–14, continuing to end of fragment; each branchia short, narrowing to rounded apex, barely longer than notopodial lobes in thoracic segments, shorter in abdominal segments (Fig. 14 D). ...