Pseudobonellia, Johnston & Tiegs, 1919

Biseswar, Ramlall, 2010, Report on deep-sea bonelliids (Echiura) from the East Equatorial Atlantic Ocean, Zoosystema 32 (1), pp. 139-154 : 151

Pseudobonellia sp.

( Fig. 5D, E )

MATERIAL EXAMINED. — East Equatorial Atlantic Ocean. West African continental margin, ZAIANGO-BIOL 2, CP 09, 07°17.67’S, 12°4.67’E, 360 m, 29.VIII.2000, 1 ♀.

DESCRIPTION

Colour of trunk white in preserved specimen.Trunk sac-like, 75 mm long and 20 mm across broadest part. Integument thin and transparent. Anterior 11 mm of trunk covered with raised papillae arranged in concentric rings. Round transparent papillae sparsely distributed over rest of trunk. Single seta on right side, minute, golden-brown in colour, with curved terminal blade terminating in pointed tip ( Fig. 5D ). Left seta is missing, probably fallen off. Interbasal muscle is absent.

Internally, only small part of foregut is present, rest of alimentary system is missing. Coelom filled with oval, pellet-like faeces. Gonoducts one pair, sac-like, located posterior to ventral setae, distal ends damaged ( Fig. 5E ). Gonostome not seen, probably damaged due to poor preservation. Male tube, small, located between proximal ends of gonoducts. Neurointestinal vessel is single throughout, opening into ventral vessel anterior to gonoducts ( Fig. 5E ). Anal vesicles not seen, probably damaged.

REMARKS

The genus Pseudobonellia is distinguished in possessing a bifid proboscis; trunk with two ventral setae; two gonoducts with distally located gonostomes and branched anal vesicles. Male carried in a small blind tube that projects into the coelom between the genital pores.

The genus Pseudobonellia contains a single species P.biuterina described originally by Johnston &Tiegs (1919) from specimens collected from the Great Barrier Reef. Edmonds (1960, 1987) recorded and redescribed this species from specimens collected from Queensland and Western Australia.The present specimen has been assigned to the genus Pseudobonellia on account of the presence of two ventral setae, two gonoducts and a thin and transparent integument. Another feature in the present specimen is the presence of a male tube. This is the first record of the occurrence of this genus in the South-East Atlantic.

Figures

FIG. 5. — A, B, Protobonellia mitsukurii Ikeda, 1908; A, ventral view of female; B, ventral seta; C, Protobonellia sp., ventral view of female; D, E, Pseudobonellia sp.; D, ventral seta; E, gonoducts; F, Zenkevitchiola sp., ventral view of female; G, H, Bruunellia sp.; G, posterior end of trunk of female showing anal rosette;H, posterior end of trunk cavity showing rectum and anal vesicle.Abbreviations: ar, anal rosette;av, anal vesicle;gd, gonoduct;mt, male tube; nc, nerve cord; niv, neurointestinal vessel; oav, opening of anal vesicle; pr, proboscis; re, rectum; se, seta; vv, ventral vessel. Scale bars: A, H, 2 mm; B, E, 1 mm; C, D, F, 0.25 mm; G, 5 mm.