Gametogenic cycle of Ophioderma januarii, a common Ophiodermatidae (Echinodermata: Ophiuroidea) in southeastern Brazil

Abstract

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)This study describes the gametogenic cycle of Ophioderma januarii Luken, 1856, a common species of ophiuroid in Southeastern Brazil. The specimens were collected during the project "Biodiversidade Bentica Marinha no Estado de Sao Paulo-BIOTA/FAPESP-Bentos Marinho" (Marine benthic biodiversity in the State of Sao Paulo-BIOTA/Fapesp-Marine Benthos) which was conducted off the northern coast of the state of Sao Paulo. Specimens were captured monthly between February 2001 and December 2002. Due to the low number of individuals the monthly data was grouped in seasons (spring to winter). A total of 101 specimens were obtained: 33 in spring, 10 in summer, 23 in autumn, and 35 in winter. The gonads of eighty-eight individuals (45 females, 42 males, and one hermaphrodite) were analyzed histologically. The male and female gametogenic cycles were classified into five different gonadal stages, which were analyzed separately. The reproductive pattern could be defined through histological analyses of male and female gonads, together with oocyte diameter frequency. Some general conclusions could also be reached: this is a gonochoric species that reproduces year-round but increases its gonadal activity during summer; based on the size of its mature oocytes, it has lecithotrophic development. Apparently, its recruitment is enhanced in late summer, and smaller individuals are more frequent during autumn and winter.261118126Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)FAPESP [02/04298-0