Bradabyssa capensis (Day, 1961) 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 : 62-64

Bradabyssa capensis (Day, 1961) n. comb., n. status

Figure 31

Brada villosa capensis Day, 1961: 510 –512, Fig. 9g –m .—Day 1967: 656–658, Fig. 32.1k–q.

Type material. Southern Africa. Paratype ( BMNH 1963.1.131), off South coast of Cape Province, Station SCD- 143D (34°45' S, 22°05' E), 95 m, 28 Aug. 1960, J.H. Day, coll.

Description. Paratype (BMNH 1963.1.131) complete, anterior region with most anterior sediment particles eroded ( Fig. 31A ); dissected anteroventrally. Body more or less rectangular, truncate in both ends; 10 mm long, 1.8 mm wide, cephalic cage 1 mm long, 37 chaetigers. Papillae sparse, filiform, finely capitate, with large sediment particles basally and medially; dorsal papillae arranged in up to 3 transverse series per segment ( Fig. 31B ). Each papilla long, adherent large sediment particles forming complete cover; individual papillae not easily detected.

Head exposed through dissection ( Fig. 31C ). Prostomium low cone, pale. Eyes not seen. Caruncle poorly developed, median and lateral keels low, continued posteriorly reaching branchial membrane posterior margin. Palps missing. Lips eroded.

Branchiae sessile on branchial plate, arranged into two lateral groups, filaments in concentric rows, each group with about 20 filaments ( Fig. 31D ). Size relative to palps unknown. Nephridial lobes not seen, probably eroded. Cephalic cage short, chaetae as long as 1/10 body length or about half as long as body width. Chaetiger 1 forming cephalic cage; chaetae arranged in short dorsolateral series; 4–5 notochaetae and 2–3 neurochaetae per bundle. First neuropodia not projected or swollen.

Anterior dorsal margin of first chaetiger eroded, probably papillated. Chaetal transition from cephalic cage chaetae to body chaetae abrupt; large aristate neurospines present from chaetiger 2. Ventral gonopodial lobes not seen. Parapodia well developed, lateral; median neuropodia ventrolateral. Notopodia and neuropodia close to each other. Notopodia with chaetal lobe rounded, with 1–2 inferior papillae, up to 1/3–1/4 as long as notochaetae; neuropodia larger rounded lobes, with a few marginal papillae (probably eroded).

Median notochaetae arranged in short transverse series, all notochaetae multiarticulate capillaries, articles small in short basal region, long medially and distally ( Fig. 31E ), 4 per bundle, as long as 2/3 body width. Neurochaetae multiarticulate capillaries in chaetiger 1; aristate neurospines from chaetiger 2, rings small ( Fig. 31 F ), subdistally hyaline.

Posterior region tapered into a blunt cone; pygidium without anal cirri.

Remarks. Brada villosa var. capensis Day, 1961 was based upon four specimens, one juvenile (Sta. WCD 64), and three adults (Sta. SCD 143), including the holotype and the paratype detailed above. Day proposed it as a subspecies because it has longer papillae than the parental form, and the distal third of neurospines is hyaline. According to the ICZN (1999, Art. 45.6.3) this has to be regarded as an infrasubspecific name; however, because it was listed as a subspecies by Hartman (1965:60), it was made available as a subspecific group name (ICZN 1999, Art. 45.6.4.1). This subspecies differs from the parental form as much as other distinct species do (see key above); consequently, it is elevated in rank and regarded as an independent species.

Bradabyssa capensis (Day, 1961) n. comb., n. status, closely resembles B. marchilensis (Hartmann-Schröder, 1965) n. comb. because both species have 37 chaetigers and 3–4 transverse series of dorsal papillae, to which sand particles adhere. They differ in the length of notochaetal articles: in B. capensis the body is small (10–15 mm long) and its notochaetae have articles short basally, and long medially and distally, whereas B. marchilensis is larger (30 mm long), and its notochaetae have all long articles.

Distribution. Cape Province, South Africa, in 95 m water depth.

Figures

FIGURE 9. Bradabyssa mexicana n. sp., holotype (LACM 7228). A. Dorsal view. B. Anterior end, dorsal view, bluish after methyl-green staining. C. Ventral view. D. Head, frontal view, cut open to show branchial scars, palps and branchiae removed, greenish after methyl-green staining (Br: branchial scars, PS: palp scar). E. Chaetiger 10, neurochaetae (inset: neurochaetal tips). Scale bars: A: 0.8 mm, B: 0.3 mm, C: 1.1 mm, D: 0.2 mm, E: 60 µm.

FIGURE 31. Bradabyssa capensis (Day, 1961) n. comb., n. status, paratype (BMNH 1963.1.131). A. Dorsal view, anterior region sediment particles eroded. B. Anterior end, dorsal view. C. Anterior end, ventral view. D. Head, frontal view after methyl-green staining, palps and left branchial plate filaments removed (BF: branchial filament, Br: branchial scars, PS: palp scar). E. Chaetiger 18, left parapodium, notochaetae (insets: basal and medial regions). F. Same, neurochaetae (insets: basal, medial and subdistal regions). Scale bars: A: 0.9 mm, B: 0.4 mm, C: 0.3 mm, D: 0.1 mm, E: 130 µm, F: 80 µm.