Sluiterina flabellorhynchum Murina, 1976

Biseswar, Ramlall, 2010, Report on deep-sea bonelliids (Echiura) from the East Equatorial Atlantic Ocean, Zoosystema 32 (1), pp. 139-154 : 144-146

Sluiterina flabellorhynchum Murina, 1976

( Fig. 3 A-D)

MATERIAL EXAMINED. — East Equatorial Atlantic Ocean. West African equatorial margin, BIOZAIRE 2, KGS 43, stn R, 05°47.975’S, 09°42.422’E, 3164 m, 28.XI.2001, 1 ♀.

GulfofGuinea, BIOZAIRE3, CP17, stnR3,05°48.6960’S, 09°43.9829’E, 3156 m, 30.XII.2003, 2 ♀♀. — CP 11, stn ZB-D, 05°50.5840’S, 008°20.0380’E, 3978 m, 20.XII.2003, 1 ♀. — CP 21, stn R 9, 05°47.4990’S, 009°43.8038’E, 3130 m, 3.I.2004, 1 ♀. — CP 18, stn R 4, 05°48.1530’S, 009°43.9136’E, 3142 m, 30.XII.2003, 1 ♀.

DESCRIPTION

Colour of proboscis is pink, trunk is reddish-brown in preserved state. Proboscis is truncate, 19-115 mm long with two small lobes at distal end ( Fig. 3A ). Lateral margins of proboscis curl inwards and unite at base forming cup around mouth. Trunk is cylindrical, 32-77 mm in length and 11-17 mm across broadest part. Integument is thick and opaque. Papillae minute, arranged in rings on anterior half of trunk; in posterior half integument is smooth. Genital pore is conspicuous about 6 mm away from anterior tip of trunk ( Fig. 3A ). Ventral setae absent. Anus located on small, conical projection.

Single, tubular gonoduct is located on left side of nerve cord ( Fig. 3B ). gonostome funnel-shaped, opening in middle of gonoduct. Gonostomal lips petaloid. Gut contents moulded into oval faecal pellets. Prominent dorsal vessel arises from wall of intestine, passes anteriorly dorsal to pharynx and enters proboscis ( Fig. 3C ). Neurointestinal vessel is single throughout. Anal vesicles are two slender sacs, 20 mm in length bearing densely aggregated tubules terminating in ciliated funnels ( Fig. 3D ).

REMARKS

The genus Sluiterina is distinguished by the presence of a truncate proboscis. Lateral margins of the proboscis fuse at the base to form a shallow cup around the mouth. The single gonoduct has a gonostome that may be basal or central in position. Ventral setae are absent.

Five species are currently assigned to the genus, namely, S. sibogae ( Sluiter, 1902) , S. vitjazi Murina, 1976 , S. flabellorhynchum , S. alba Murina, 1978 and S. kaikourae Edmonds, 1985 . The original description of the species S. flabellorhynchum is based on specimens from the Scotia Sea (South Atlantic). This species was recorded and described from the Antarctic by Saiz-Salinas et al. (2000).The specimens on hand closely approach the description given by Murina (1976). Sluiterina flabellorhynchum differs from all the other species in the genus in possessing a gonostome that opens in the middle of the gonoduct. The discovery of this species in the South-East Atlantic is a new record for the region and considerably extends its range of distribution.

Figures

FIG. 3. — A-D, Sluiterina flabellorhynchum Murina, 1976;A, ventral view of anterior part of female; B, gonoduct; C, anterior end of trunk cavity showing the blood system; D, anal vesicles; E, F, Sluiterina sibogae (Sluiter, 1902); E, ventral view of anterior part of female; F, gonoduct.Abbreviations:av, anal vesicle;dv, dorsal vessel;gd, gonoduct;gp, genital pore;gs; gonostome;int, intestine;nc, nerve cord; niv, neurointestinal vessel; ph, pharynx; pr, proboscis; vv, ventral vessel. Scale bars: A, C, 4 mm; B, F, 2 mm; D, 1 mm; E, 5 mm.