Bradabyssa indica, Salazar-Vallejo, 2017

Salazar-Vallejo, Sergio I., 2017, Revision of Brada Stimpson, 1853, and Bradabyssa Hartman, 1967 (Annelida, Flabelligeridae), Zootaxa 4343 (1), pp. 1-98 : 21-23

Bradabyssa indica n. sp.

Figure 8

Type material. Holotype ( MNHN IA-Type 1797) and one paratype ( MNHN IA-Type 1797b), off SW Sri-Lanka, R.V. Marion Dufresne, SAFARI II Cruise, Sta. 2 (05°37' N, 78°24' E), 3660 m, Jul. 1981).

Description. Holotype (MNHN IA-Type 1797) an anterior fragment, damaged. Body cylindrical, depressed after mounted for observation; 3 mm long, 1 mm wide, cephalic cage 1 mm long, 9 chaetigers. Tunic thick, continuous, carrying large sediment particles ( Fig. 8A ). Body papillae not seen, surface rough dorsally and ventrally ( Fig. 8B ), but venter with smaller foreign particles.

Cephalic hood not exposed. Anterior end not dissected to avoid further damage. Cephalic cage present, chaetae as long as body width. Chaetiger 1 involved in cephalic cage; chaetae in short ventrolateral series, 1–2 notochaetae (mostly broken) and 2–3 neurochaetae per ramus.

Anterior dorsal margin of first chaetiger smooth ( Fig. 8C ). Anterior chaetigers without especially long papillae. Chaetigers 1–3 of similar length. Chaetal transition from cephalic cage to body chaetae abrupt; chaetiger 4 with aristate neurospines. Gonopodial lobes not seen.

Parapodia poorly developed, chaetae emerge from body wall. Parapodia lateral; median neuropodia ventrolateral. Notopodia and neuropodia close to each other, each with 1–2 long papillae.

Median notochaetae broken; all notochaetae multiarticulate capillaries, articles short, as long as 2/3 body width. Neurochaetae multiarticulate capillaries in chaetigers 1–3 ( Fig. 8D, E ); aristate neurospines from chaetiger 4, each with very short rings basal- and medially, distally hyaline, flat, 2–3 per bundle ( Fig. 8F ).

Posterior end unknown.

Variation. Paratype 3 mm long, cephalic cage twisted, about 0.6 mm long, 12 chaetigers.

Remarks. Bradabyssa indica n. sp. resembles B. minuta ( Amoureux, 1986) n. comb. (see below), because they have a similar body shape. As indicated in the key above, B. indica and B. mexicana n. sp. differ from other species in the group by having neurospines from chaetiger 4. They differ from each other in the relative size of cephalic cage chaetae; in B. indica they are as long as the body, whereas they are only longer than body width in B. mexicana .

Etymology. The specific name indicates that the species was found in the Indian Ocean. Distribution. Laccadive Sea, off Sri-Lanka, in 3660 m depth.

Figures

FIGURE 8. Bradabyssa indica n. sp., holotype (MNHN IA-Type 1797). A. Dorsal view. B. Ventral view. C. Anterior end, chaetigers 1 – 3, dorsal view. D. Chaetiger 1, basal notochaetal region. E. Chaetigers 2 – 3, left parapodial neurochaetae, ventral view. F. Chaetiger 4, left parapodial neurochaetae, ventral view. Scale bars: A: 0.4 mm, B: 0.3 mm, C: 0.1 mm, D – F: 40 µm.