Chaetozone ruffi Blake, 2015, new species

• Main Author: Blake, James A.
• Format: Other/Unknown Material
• Language: unknown
• Published: 2015
• Subjects: Biodiversity; Taxonomy; Animalia; Annelida; Polychaeta; Terebellida; Cirratulidae; Chaetozone; Chaetozone ruffi; Arctic; Malmgren; Noto; Beaufort Sea; Prudhoe Bay
• Online Access: https://zenodo.org/record/5664938; https://doi.org/10.5281/zenodo.5664938

Chaetozone ruffi new species Figures 9–10 Chaetozone setosa: Busdosh 1984. Not Malmgren 1867. Material examined. Alaskan Arctic, Beaufort Sea, Prudhoe Bay, 0 5 Aug 1983, 70° 23.9 ʹN, 148 °26.0ʹW, 3 m, push cores, coll. M. Busdosh, Waterflood 6 project, R/V Annika Marie, Sta. 15 - 1, holotype (LACM-AHF Poly 6540), 3 paratypes (LACM-AHF Poly 6541). Description. A moderate-sized species, holotype 12 mm long, 1.0 mm wide with 96 setigerous segments; paratypes similar in size with 90–100 setigers. Body expanding slightly in anterior segments, narrowing gradually along body; posterior third of body with full cinctures of spines. Middle body dorsoventrally flattened, with deep ventral groove continuing to near posterior end; mid-dorsal groove present along most of body (Figs. 9 A, 10 A–B), becoming deeper and more distinct in posterior setigers where elevated membranes and cinctures of spines overlap and enhance groove. Color in alcohol light tan with no body pigment. Prostomium narrow, pointed on anterior margin (Fig. 9 A–B), with slit-like nuchal organ on posterolateral margin (Fig. 9 B); eyes absent. Peristomium broad, with 2–3 weak annulations, forming one large anterior ring and two narrow posterior rings; all rings weakly defined (Fig. 9 A–B) and variable in size and development between specimens; distinct achaetous segment not apparent; last peristomial ring bearing tentacles and first pair of branchiae, with latter arising lateral to tentacles (Fig. 9 A–B). Second pair of branchiae arising from setiger 1, continuing on subsequent segments; branchiae of anterior third of body long, thick, branchiae of middle and posterior segments, short and thin where present. Anterior noto- and neurosetae all simple capillaries arranged in single rows of 6–8 notosetae and neurosetae; capillaries increasing in middle body segments to 15 or more in notopodia and 10–12 in neuropodia; some capillaries long, but extremely long natatory-like capillary setae absent in mature individuals. Neuropodial acicular spines from setigers ...