Bradabyssa rugosa Salazar-Vallejo 2017, n. comb.

Bradabyssa rugosa (Hansen, 1880) n. comb.

Figures 1C–F, 17

Trophonia rugosa Hansen, 1880: 231, Pl. 4, Figs 4–7.— Hansen 1882: 38 –39, Pl. 7, Figs 9–12.— Oug et al. 2014: 229 (syn.). Trophonia arctica Hansen, 1880: 230, Pl. 5, Figs 1–3.— Hansen 1882: 39, Pl. 7, Figs 17–20.

Brada rugosa.— Støp-Bowitz 1948a: 37 –40, Fig. 10 (syn.).— Støp-Bowitz 1948b: 41 –42, map.— Jirkov & Filippova 2001: 355, Figs 1–4.— Oug et al. 2011: 13, Figs a, b. (repeated from Støp-Bowitz 1948a).

Type material. Northwestern European Arctic Ocean. Syntypes (ZMUB 2288), Norwegian North Atlantic Expedition, Sta. 366 (79°35' N, 11°17' E), NW Svalbard, 68 m (after Hansen 1882:23), 1877.

Description. Two syntypes (ZMUB 2288, Figs 1C, 17A, B) with all neurochaetae broken. One syntype whitish (more damaged), body truncate in both ends, soft, dissected anteroventrally and several parapodia removed; the other syntype yellowish, truncate, wider anteriorly, tapered posteriorly, rough, several parapodia removed; 34–38 mm long, 7–8 mm wide, cephalic cage 5.0– 5.5 mm long, 21–25 chaetigers. Tunic rugose, dorsal and ventral papillae forming incomplete transverse tuberculose ridges, arranged in 3–4 transverse rowsseries per chaetiger; each tubercle covered by a thin layer of fine sediment particles.

Cephalic hood not exposed; dissected syntype without anterior end (missing). Additional dissection avoided. Anterior end features unknown.

Cephalic cage chaetae as long as 1/6 body length, or more than half as long as body width. Chaetiger 1 involved in cephalic cage; chaetae arranged in short lateral series; 10 notochaetae and 10 neurochaetae per side (most remain in yellowish syntype, Fig. 17C).

Anterior dorsal margin of first chaetiger papillated, papillae small, abundant (most eroded). Anterior chaetigers without especially long papillae. Chaetigers 1–3 of similar length but notopodia in chaetiger 2 larger than others. Chaetal transition from cephalic cage to body chaetae abrupt; chaetiger 2 with neurospines (broken). Gonopodial lobes small, rounded, darker than surrounding areas, present in chaetiger 5 (Fig. 17C, D).

Parapodial lateral, well developed (Fig. 1D); median neuropodia ventrolateral. Notopodia and neuropodia close to each other. Notopodia low conical lobes with 3–4 tapered infrachaetal papillae, reduced to 1–2 in posterior parapodia. Neuropodia larger rounded lobes with 4–6 postchaetal papillae.

All notochaetae multiarticulate capillaries; median notochaetae arranged in tufts (or a short transverse series), few remain, about 6 per ramus, 1–2 smaller, thinner, with long articles, 3–4 longer, thicker, with very short articles basally, medium-sized medially and distally (Fig. 1E), as long as 1/3 body width. Neurochaetae multiarticulate capillaries in chaetiger 1. Aristate brown neurospines (after original description) from chaetiger 2 (bases remain), arranged in C-shaped patterns (facing posteriorly), 5–7 per bundle, with long, straight aristae (Fig. 1F).

Posterior end rounded, truncate (Fig. 17E); pygidium with anus terminoventral, vertical slit; anal cirri absent.

Remarks. Bradabyssa rugosa (Rathke, 1843) n. comb. is unique in having 3–4 transverse low incomplete tuberculose ridges or verrucae per segment. There are other species with 3 transverse series of tubercles per segment (see key above) but this is the only species possessing flat, polygonal ridges.

Støp-Bowitz (1948a:38) noted that the type specimens above were placed together before he could study them, and that probably because they were labelled as Trophonia rugosa, despite the fact they were the original type material for T. rugosa Hansen, 1880 and T. arctica Hansen, 1880, Støp-Bowitz (1948a:38) regarded them as synonymous, Oug et al. (2014:229) agreed upon this conclusion, and I concur. The shorter, slightly darker specimen corresponds to the former, and the whitish, slightly larger specimen to the latter. Consequently, because there are two type specimens in a single container, they are regarded as syntypes even though historically they were regarded as separate species.

Distribution. Northwestern European Arctic Ocean, in shallow waters.