Reproduction of the temperate octocoral Tripalea clavaria (Octocorallia, Anthothelidae) from sublittoral outcrops off Mar del Plata, Argentina

EXCOFFON, A. C.; F. H. ACUÑA; M. O. ZAMPONI; G. N. GENZANO

JOURNAL OF THE MARINE BIOLOGICAL ASSOCIATION OF THE UNITED KINGDOM

Marine Biological Association of the United Kingdom

Lugar: Plymouth; Año: 2004 vol. 84 p. 695 - 699

0025-3154

In Mar del Plata the octocoral Tripalea clavaria is highly abundant on the different quartzitic rocky outcrops 18-20 m deep. Reproduction aspects of T. clavaria including its ditribution and population structure have been described. Monthly sampling and observations were carried out by SCUBA diving fron November 2000 to October 2001 at Banco del Medio (38°10´S 57°28´W). Tripalea clavaria occurs in patches; most colonies were 3.0-8.9 cm in height. The species appears to be gonochoric brooder. Female colonies were significantly more abundant than males, which could be identified only from February to June, when spermaries were present. Oocytes were found even in very small colonies (from 3.5 cm height), being 40 to 200 um in diameter, the predominant size-group around the year. development of the oocytes required several months, beginning in May and endidng with the production of larvae from March to May. Young, stalked oocytes were found at hte base of the polyps attached to the mesenteries in May-June. During the following six months they grew in size; maximal oocyte diameter eas 700 um, observed in April/May. Asexual reproduction was negligible, indicating that population maintenance is based on sexual reproduction.