REPRODUCTIVE ASPECTS OF THE PURPLE CRAB HOMALASPIS PLANA (MILNE-EDWARDS, 1834) (CRUSTACEA: BRACHYURA: XANTHIDAE) IN THE RELONCAVI GULF, CHILE

Abstract

Four hundred and nineteen adult and juvenile crabs Homalaspis plana were sampled between may 1989 and december 1991. The sex ratio (2.8 females: 1 male) suggests a polyginic mating type. Mating took place during summer and was observed in specimens kept in the laboratory: the couple is established when the female molts, but copulation is carried out several days later, when the female's carapace is already hard. The ovary matures after fertilization and spermatophores are retained in two large spermathecae, whose volume decreases as the gonad develops. Ovigerous females were found between june and september and their mínimum size at sexual maturity was about 80 mm in carapace width. Fecundity ranged between 180.000 and 700.000 eggs and the larval cycle occurred in spring, between october and january.