Bradabyssa intoshi (Caullery, 1944) 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 : 69-70

Bradabyssa intoshi (Caullery, 1944) n. comb.

Figure 35

Trophoniella intoshi Caullery, 1944: 38 –39, Fig. 29A–E .—Bleeker & van der Spoel 1992: 163. Brada sp. Al-Hakim & Glasby 2004: 38.

Type material. Southeastern Indian Ocean. Holotype of Trophoniella intoshi ( ZMA 1600 ), off Northern tip of Sumba Island , Sawu Sea, R.V. Siboga, Sta. 52 (09°31' S, 119°56' E), 959 m.

Additional material. Southeastern Indian Ocean. Anterior fragment ( MZB 59 ), Sta. NT 8A (04°17.01' N, 108°19.00' E), Natuna Timur , Indonesia, 71 m, 30 Jul. 2001, I. Al-Hakim, coll. (3 mm long, 1.3 mm wide, cephalic cage 1 mm long, 12 chaetigers). Anterior fragment ( MZB 102 ), Sta. NB 17B (03°44.82' N, 107°58.76' E), Natuna Barat , Indonesia, 48 m, 3 Aug. 2001, I. Al-Hakim, coll. (3.5 mm long, 1 mm wide, cephalic cage 1 mm long, 14 chaetigers). Northern Indian Ocean , Persian Gulf. One specimen ( SMF 20036), juvenile, GEOMAR 91 cruise, Sta. PG 1 KG, 1991, H. Zetsche, coll. (3.1 mm long, 0.8 mm wide, cephalic cage 0.6 mm long, 17 chaetigers). Bay of Bengal. Four specimens ( LACM 5323 ), juveniles, International Indian Ocean Expedition, Sta. RH 30, Madras, 2.5 km SE off harbor, directly east of the University building, 15 m, 18 Mar. 1964, H. Sanders, coll. (0.9–1.5 mm long, three specimens with 12 chaetigers; smaller specimen without chaetae and with about 15 feebly-defined segments; sediment particles pattern and papillae, although very small, resembling those present in the other specimens). Eighteen specimens ( LACM 5324 ), International Indian Ocean Expedition, Northern Indian Ocean, Sta. RH 26, off Porto Novo, Madras State (11º22' N, 79º43' E), 20 m, 14 Mar. 1964, H. Sanders, coll. (1.0– 4.2 mm long, 0.2–1.2 mm wide, cephalic cage 0.5–1.1 mm long, 13–23 chaetigers; some with anterior end exposed, 8–12 branchial filaments per side).

Description. Holotype (ZMA 1600) broken in two portions; anterior fragment darker, with abundant sand grains over body ( Fig. 35A ), posterior fragment smashed, without sediment, regenerating the distal portion. Body fusiform, depressed, truncate anteriorly, posteriorly tapered; 8 mm long, 2.5 mm wide, cephalic cage 2.3 mm long, 18 chaetigers. Tunic papillate; papillae elongate, capitate, with sand particles, especially along dorsum, arranged in 3–4 series per segment; notopodial papillae very long (4–6 times as long as dorsal ones).

Cephalic hood not exposed; not dissected to avoid further damage. Cephalic cage chaetae delicate, less than 1/3 body length, or as long as body width. Chaetiger 1 involved in cephalic cage; chaetae arranged in short dorsolateral series, with about 2 chaetae per bundle.

Anterior dorsal margin of first chaetiger papillated, papillae sparse, elongate, capitate. Chaetigers 1–3 decreasing in size posteriorly. Chaetal transition from cephalic cage to body chaetae abrupt; aristate neurospines present from chaetiger 2. Gonopodial lobes in chaetiger 5 ( Fig. 35B , arrow).

Parapodia well developed; lateral; median neuropodia ventrolateral ( Fig. 36C ). Notopodia and neuropodia close to each other. Notopodia short conical lobes with long capitate papillae, 3–4 per ramus, postchaetal. Neuropodia larger conical lobes with elongate capitate papillae, as long as notopodial ones (most broken).

Median notochaetae arranged in short series, transverse to body axis; all notochaetae multiarticulate capillaries, articles short basally and medially, longer distally, 5–6 per bundle, about as long as 2/3 body width. Neurochaetae multiarticulate capillaries in chaetiger 1; aristate neurospines from chaetiger 2, arranged in transverse series, 5 per bundle. Each with very short rings basally and medially, distally hyaline ( Fig. 35C , inset).

Posterior end in regeneration; pygidium short cone with anus terminal, anal cirri absent.

Remarks. In the remarks for Trophoniella intoshi, Caullery (1944:39) stated: “… celle qu’elle rappellerait le plus serait Brada whiteavesii McIntosh, du Challenger. ” This translates as: “… the most similar species would be B. whiteavesii McIntosh , of the Challenger (Expedition).” However, despite this statement of its affinity with Brada species, he described it under a different genus.

Bradabyssa intoshi (Caullery, 1944) n. comb., closely resembles B. capensis (Day, 1961) n. comb., n. status: both species have 3–4 transverse series of papillae per segment and gonopodial lobes in chaetiger 5. They differ because in B. intoshi notopodial papillae are extremely long, at least 2/3 as long as notochaetae, whereas in B. capensis , notopodial papillae are shorter, only as long as 1/3 notochaetal length. These two species were described from different environments and in geographically widely separated localities; B. intoshi was also collected in deeper water (959 m), whereas B. capensis was found in shallower water (1–499 m). The shallow water Indonesian specimens (MZB 59, 102) have very long parapodial papillae and are thus included herein as B. intoshi . Furthermore, the finding of a smaller specimen of only 0.9 mm in length lacking chaetae altogether, might imply that the species has a short lecitrophic development and that (most?) chaetae may arise once the juvenile settles on the bottom.

Distribution. South China to Sawu Seas, and a disjunt records in Bengal Bay and Persian Gulf, in 48–954 m; however, this wide depth range might be an artifact and more than one species could be included under the same name, but by using these morphological features, its separation was not possible.

Figures

FIGURE 29. Bradabyssa tenebricosa (Berkeley, 1966) n. comb., n. status. A. Holotype (BCPM 973.60.14. N). B. Same, anterior region, ventral view, anterior left seven parapodia (arrow points to gonopodial lobe). Non-type specimen (BCPM 986.86.11), head, oblique frontal view, palps and branchiae removed (Br: branchial scars, Ca: caruncle, PS: palp scar). D. Nontype specimen (BCPM 974.17.4), chaetiger 20, right parapodium. E. Same, chaetiger 10, right parapodium, basal, medial and distal notochaetal regions. F. Holotype (BCPM 973.60.14. N), posterior end, oblique ventral view. Scale bars: A: 1.2 mm, B: 0.3 mm, C: 0.2 mm, D: 130 µX mm, E: 60 µm, F: 0.5 mm.

FIGURE 35. Bradabyssa intoshi (Caullery, 1944) n. comb., holotype (ZMA 1600). A. Anterior end, dorsal view. B. Anterior end, ventral view (arrow points to base of left gonopodial papillae). C. Chaetiger 13, right parapodium (inset: neurochaetal tips). Scale bars. A: 0.6 mm. B: 0.5 mm, C: 50 µm.

FIGURE 36. Bradabyssa jirkovi n. sp., holotype (SIORAS 6085). A. Dorsal view. B. Anterior end, dorsal view. C. Same, ventral view (arrow points to gonopodial lobes, neurochaetae removed). Paratypes (ECOSUR 186): D. Head, frontal view, palps removed, branchiae on site. E. Same, close-up, right neuropodia from chaetigers 4 – 7 (arrow points to gonopodial lobe, most papillae brushed off). F. Chaetiger 14, right parapodium, notochaetal basal, subdistal and distal regions. G. Same, neurochaetal basal, medial and distal regions. Scale bars. A: 1.5 mm, B: 0.9 mm, C: 0.6 mm, D: 0.3 mm, E: 0.2 mm, F: 40 µm, G: 80 µm.