Juan J. A. Laverde-Castillo

A.A. 40177, Santa Fe de Bogotá 1, Colombia.

RESUMEN

Se registra la presencia en el Caribe colombiano del poliqueto Eulepethidae Grubeulepis westoni, ampliando su rango de distribución al Caribe sur. Se examinaron tres especímenes adultos colectados en sedimentos blandos a 12 y 60 m de profundidad en la bahía de Portete y la bahía de Santa Marta respectivamente.

The family Eulepethidae Chamberlin, 1919 comprises scale worms characterized by bearing 12 pairs of anterior elytra - increasing in length posteriorly-, biramous parapodia, with simple setae, and distally hammer-headed neuraciculae. Based on the shape of the elytral borders, presence or absence of small posterior elytra, posterior dorsal lamellae, and large ventral lamellae on the bases of median neuropodia, six genera are recognized at the present time (Pettibone, 1986). Members of the genus Grubeulepis Pettibone, 1969 have short bodies consisting of up to 40 segments with 12 pairs of fimbriated elytra, dorsal cirri on segments 3 and 6,10-13 pairs of branchiae, and posterior dorsal lamellae beginning on segments 26-29, continuing posteriorly (Pettibone, 1969).

Grubeulepis is represented in American waters by seven species (cf. Amaral and Nonato, 1984 and Pettibone, 1986), none of which have been previously cited from Colombian coasts. This note reports and describes material of G. westoni collected from two localities in the Colombian Caribbean, its most southerly record. The specimens are stored in the Polychaete collection of the Instituto de Investigaciones Marinas de Punta de Betín (INVEMAR-A), Santa Marta, Colombia, and author's collection (L - C). Methods for counting and measuring follow Pettibone (1986).

Grubeulepis westoni Pettibone, 1986
Fig. 1 a-f

Grubeulepis cf. ecuadorensis, Uebelacker, 1984:24-9, figs. 24-5,24-6a-j [not G. ecuadorensis Pettibone, 1969].

Grubeulepis westoni Pettibone, 1986:40-49, fig. 33-42.

Material Examined. Bahía de Portete (12°07'N, 72°02'W): VI-1987,12 m, mud with calcareous rubble, 1 adult (INVEMAR-A 377: 32 mm long, cTmm wide, with 39 segments). Bahía de Santa Marta (11°15'N, 74°14'W): 15-XII-1988, 60 m, fine sand, 2 adults (INVEMAR-A 412: 34 x 8 mm, with 39 segments, and L-C 967: 25 x 7 mm, 38 segments).

Remarks. Adults of G. westoni are distinguished from its other Caribbean congeners by the following set of characters. The first pair of elytra lack papillae (fig. 1a). The lateral processes of the fimbriated elytra are entire (fig. 1b-e). The neurosetae of the anterior segments are widely limbate with short tapering tips, and the upper neurosetae of the posterior lamelligerous segments are stouter than the lower ones, curved downward, with tapered tips and are finely spinous along the bend. On the other hand, G. westoni most closely resembles G. ecuadorensis Pettibone, 1969, reported from Ecuador. They only disagree in that the former has a single acicular neuroseta only on segment 3 (fig. 1f), while the latter has such setae on segments 3 to 8. The adult specimens here examined agree in most features with Pettibone's original description of G. westoni. The only difference found was in the number of digitiform lateral processes of elytra, ranged from 3-4 (on 2nd elytra) to 13-20 (on 12th elytra) in Pettibone's material, while in the Colombian material it ranged from 2 to 9-12. This difference demonstrates the wide variability of this feature, perhaps related to differences in habitat or physiological conditions.

Pettibone (1986) recorded G. westoni from several western Atlantic localities northern 16°55'N -the East coast of the United States, Gulf of Mexico, Belize, and Puerto Rico. The new records extend the distribution of this species to south Caribbean waters, where it was found inhabiting soft sediments at moderate dephts both in inshore and offshore waters, Bahía de Portete and Bahía de Santa Marta, respectively. These two areas, separated by ca 280 km, are characterized by the occurrence of up-welling during the dry season as pointed out by Fajardo (1979) and Ramirez (1983), respectively. The presence of up-welling in notheastern part of Colombian coast could explain the occurrence of species which G. westoni otherwise seems to be characteristic of Subtropical Western Atlantic region.

ACKNOWLEDGMENTS

Bahía de Portete material was collected during an environmental evaluation carried out by INVEMAR under a Contract of Asociación CARBOCOL/INTERCOR. Bahía de Santa Marta specimens come from dredged samples taken as a part of the Programa Ecosistemas Marinos/INVEMAR, with financial support from Fondo Colombiano de Investigaciones Científicas "Francisco José de Caldas" -COLCIENCIAS. Special thanks to Dr. J. M. Díaz who provided material for this study and reviewed an earlier draft of this note. I indebted to Dr. L. Botero whose comments improved the English version of the manuscript. I am also grateful to my colleagues S. Schoppe and J. Garzón for their helpful technical assistance. The comments of two anonymous reviewers are gratefully acknowledged. Space, equipment, and typing facilities were gently provided by INVEMAR.

LITERATURE CITED

1 Amaral, A. C. and E. F. Nonato. 1984. Anelldeos Poliquetos da Costa Brasileira 4: Polyodontidae, Pholoidae, Sigalionidae e Eulepethidae. CNPq - Coordenacao Editorial, Brasilia. 54 pages.        [ Links ]

2 Fajardo, G. 1979. Surgencia costera en las proximidades de la Península de la Guajira. Bol. Cient. CIOH-Cartagena, 2:7-19.        [ Links ]

3 Pettibone. M.H. 1969. Revision of the Aphroditoid Polychaetes of the Family Eulepethidae Chamberlin (=Eulepidinae Darboux; = Pareulepidae Hartman). Smithson. Contrib. Zool., 41:44 pages, 31 figs.        [ Links ]

4 Pettibone. M.H. 1986. Additions to the Family Eulepethidae (Polychaeta: Aphroditacea). Smithson. Contrib. Zool., 441:51 pages, 41 figs.        [ Links ]

5 Ramírez, G. 1983. Características físico-químicas de la Bahía de Santa Marta (agosto 1980-julio 1981). An. Inst. Inv. Mar. Punta de Betín, 13:111-121.         [ Links ]

6 Uebelacker, J. M. 1984. Family Eulepethidae Chamberlin, 1919. pp. 24.1-24.13, vol 3. In: J. M. Uebelacker and P. G. Johnson (eds.), Taxonomic Guide to the Polychaetes of the Northern Gulf of Mexico. 7 vols. Barry A. Vittor and Associates, Mobile, Alabama, USA.        [ Links ]