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Formation of oostegites in Porcellio dilatatus Brandt (Crustácea, Isopoda, Oniscidea) in laboratory

Woodlice were reared in laboratory in the environmental climate of the city of Curitiba, Brazil, with the purpose of getting to know the process of formation of oostegites. Two kinds of cultivation were adopted: natural populations to be controlled were kept in small glass aquariums resembling the natural environment; and, new-bom woodlice were raised each one isolated in small plastic receptacles, with a special diet until two years old or over. When adults, after recognizing their sexes, males and females were put together to copulate during one or more days, and some of the females were fertilized. After 30 days, the fertilized females realized ecdise and acquired oostegites. The complete process (copulation, fecundation, incubation and birth) occurred between 25 and 50 days. The females fertilized only once produced one or more broods, each brood varying from 10 to 30 youngs. The spermatic mass reserved in the seminal receptacle depleted after having realized one, two or, rarely, three broods; the females without sperm in the receptacle realized ecdise, lost oostegites and got again virginal aspect. Females in such condition, kept alone, isolated from males have never acquire oostegites again. Otherwise, in contact with males, once fertilized they realized ecdise and acquired new oostegites. The authors have concluded that the oostegites only are formed because of the received sperm and its continuity depends on the sperm accumulated in the seminal receptacle, for more than one brood.

Crustácea; Isopoda; Oniscidea; Porcellio dilatatus; oostegites


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