OMANA, E.C.*; SHUSTER, S.M.: The Ecology and Reproductive Biology of Paradella dianae (Crustacea: Isopoda)

Sphaeromatid isopods are distributed worldwide, primarily in shallow marine waters. Paradella dianae is a sexually dimorphic sphaeromatid isopod that inhabits many localities, including the northern Gulf of California. To examine the reproductive biology of this species, we made six collections of P. dianae from Tetraclita barnacle tests at Pelican Point, Sonora, Mexico. Our results suggest that members of this species aggregate within the barnacle tests and are not randomly distributed. We found that three male morphotypes exist within this population. We demonstrate that females are iteroparous, undergo a series of molts associated with reproductive condition, and are capable of sperm storage. Hermaphroditic individuals have been reported from one population of P. dianae; we found no evidence of this in the Pelican Point population. We note the presence of epibionts on numerous individuals of P. dianae during each collection.