Charcotus charcotus DattaGupta, 1981

Biseswar, Ramlall, 2006, Additions to the deep-sea echiuran (Echiura) fauna of the North-East Atlantic, Zoosystema 28 (4), pp. 853-864 : 855

Charcotus charcotus DattaGupta, 1981 ( Fig. 1A, B )

MATERIAL EXAMINED. — Porcupine Abyssal Plain, BEN- GAL 3, Discovery 229, stn 13200#94, 48°50.99’N, 16°26.03’W, 4847 m, 25.VII.1997, 1 ♀.

DESCRIPTION

Colour of trunk is pink in preserved state. Only basal stump of proboscis is attached to trunk, rest is missing. Mouth in an oral cup formed by inflection of lateral margins of proboscis proximally ( Fig. 1A ). Trunk cylindrical, 76 mm in length and 7 mm across broadest part. Body wall is damaged in middle region of trunk. Genital pore is located about 9 mm away from anterior end of trunk ( Fig. 1A ). Integument is thick and opaque, densely covered with flattened, elongated papillae.

Single oval gonoduct is located on right side of nerve cord; gonostome is at distal tip ( Fig. 1B ). Except for muscular pharynx and oesophagus rest of alimentary canal is missing including blood vascular system. Only distal part of one anal vesicle was found in coelom. It is tubular with sparsely distributed ciliated funnels.

REMARKS

The species Charcotus charcotus was erected by DattaGupta (1981) based on specimens from the North-East Atlantic. This species is distinguished by the presence of a truncate proboscis; mouth in an oral cup; single gonoduct with distally located gonostome and tubular anal vesicles. Except for some minor differences the present specimen closely approaches the description provided by DattaGupta (1981).

Charcotus charcotus appears to be closely related to Eubonellia longistomum DattaGupta, 1981 in possessing a single gonoduct with a distally located gonostome, tubular anal vesicles and in lacking ventral setae. Charcotus charcotus , however, differs in possessing a proboscis which forms an oral funnel proximally.

Torbenwolffia galatheae Zenkevitch, 1966 and Pseudoikedella achaeta ( Zenkevitch, 1958) are two other species that have been recorded at this station ( Biseswar 2005).

Figures

FIG. 1. — A, B, Charcotus charcotus DattaGupta, 1981; A, ventral view of anterior part of female; B, gonoduct; C, D, Jakobia similaris DattaGupta,1981;C, ventral view of anterior part of female;D, gonoduct;E-H, Jakobia densopapillata n. sp.;E, ventral view of anterior part of female; F, G, gonoducts;H, anal vesicle.Abbreviations:av, anal vesicle;gd, gonoduct;gp, gonopore;gs, gonostome;nc, nerve cord; pr, proboscis; re, rectum. Scale bars: A, 4 mm; B, 0.5 mm; C, F, 3 mm; D, G, 1 mm; E, H, 2 mm.