The postmarsupial development of Porcellio siculoccidentalis, with some data on reproductive biology (Crustacea, Isopoda, Oniscidea)

In the broader context of research on the Sicilian Porcellio imbutus-complex, the postmarsupial developmentof Porcellio siculoccidentalis Viglianisi, Lombardo & Caruso, 1992 was studied in detail. Thisresearch was conducted in the laboratory under controlled conditions, allowing us to follow the stagesof development, from the formation of the marsupium in ovigerous females until the larval stages anddevelopment of the seventh pair of legs. The timing of developmental stages and the morphological modificationsof appendages in the postmarsupial manca stages (M I–M III) are described. The manca stageM I had a duration of about one hour. Ovigerous females were collected and reared separately, and thenumber of parturial molts in the absence of males was counted. The results showed a maximum of foursuccessive parturial molts. Fecundity and fertility were evaluated as the number of eggs and embryos,respectively, inside the marsupium of the ovigerous females. Both parameters were positively correlatedwith the size of the females. The maximum numbers of eggs and embryos in the marsupium were 113 and141, respectively. Data describing the total number of postmarsupial mancas released per month indicatedthat the highest release occurred in April.