Fecundity and reproductive period of Paradella dianae and Uromunna sp. (Peracarida, Isopoda) associated with prop roots of Rhizophora mangle in a tropical coastal lagoon, SE Gulf of California, Mexico

Specimens of the estuarine isopods, Uromunna sp. and Paradella dianae living among Rhizophora mangle prop roots in a SE Gulf of California coastal lagoon system were collected from 11 stations, from October 1997 to September 1998. Among the ovigerous females, there was a positive, significant relationship between clutch size and TL for both species. The average size at first sexual maturity was estimated to be 1.54 mm with an average fecundity of 11 eggs for Uromunna sp. In the case of P. dianae, the average size at first sexual maturity was estimated to be 4.81 mm with an average fecundity of 19 eggs. On the basis of proportion and frequency of appearance of ovigerous females, prop roots in Urías seem more suitable as a reproductive habitat for Uromunna sp. than for P. dianae.