REPRODUCTION AND PROTECTED DEVELOPMENT IN PSOLUS PATAGONICUS (HOLOTHUROIDEA) FROM ARGENTINA.

GIMÉNEZ, J.; PENCHASZADEH, P. E.

Banyuls-Sur-Mer

Conferencia; 6th European Conference on Echinoderms; 2001

Psolus patagonicus (Ekman 1925) is an abundant holothuroid, living on a variety of habitats and substrata; it has been recorded inthe intertidal rocky shores and on Macrocystis pyrifera fronds and holdfasts of southem Patagonia and on live scallops(Zygochlamys patagonicus). We took monthly samples from October of 1999 to march 200 l of Psolus patagonicus, from theZygochlamys patagonicus fisheries in the are around 39° 26'S 55°56'W at 100-110m depth. Each month about 50 specimens werefixed in formol5% for later microcopical studies of the gonads. Psolus patagonicus incubates the eggs and embryos under thesole;the complete development process takes seven months. The smallest recorded incubating female was 17 mm in length andthe ñi'aXiiñúm size recorded was 23 mm. The setting ofthe eggs under the sole is realized in the months of February - March(uncleaved egg diameter of 887.72± SD26.71 11m), with a number of eggs per brooding female of 147± SD20, the embryosdevelop reaching a size of 1972.57±158.22 11min September, with number per female of 82± SD14. lndependent life is achieveáin October (2220± SD21 O 11m).