[Oogenesis of Perinereis macropus Claparede, 1870 (Annelida, Polychaeta) in the Gulf of Gabes (Tunisia)].

The polychaete Perinereis macropus (Claparède, 1870) (Nereididae) is present in the Gulf of Gabes, but its reproductive biology is unknown. An intensive study was conducted from August 2004 to July 2005 to characterize the life cycle of a population in the mouth of wadi Ferd in Gabes. The examination of sexual products allows us to describe the morphological oocytes aspects at different stages. The results show that P. macropus has an asynchronous oogenesis. Moreover, the biometric study of oocytes growth allows us to clarify the female sexual cycle. The female maturity occurs in April and the mature oocyte diameter is approximately 250+/-32.67 microm. However, spawning occurs in May, when the seawater temperature starts rising. We propose that the reproductive season stretches from March to June in the Gulf of Gabes.