Male reproductive system and espermiotaxonomy in Dromiidae: there is only one pattern of seminal fluid production, packaging sperm and sperm transfer in crabs?

Abstract

The Dromiidae family is basal in Brachyura and little known from the histo-morphological and ultrastructural point of view. The general objective will be to detect possible morphological and histological patterns of the male reproductive system, seminal fluid production, mating behavior and sperm transfer. We will also carried out the acrosome reaction and perform espermiotaxonomia in Brazilian Dromiidae, relating with the current literature, in order to understand the evolution of this group in relation to eubrachyuran. Adult individuals will be collected by trawling in Ubatuba, SP. For histological and histochemical description, the reproductive system will be processed according to historesin procedure. For sperm transfer, H. parasitica couples will be kept in aquariums and mate behavior will be filmed and described. The seminal material transfered to the female will be prepared for light microscopy and scanning electron microscopy. For the acrosome reaction steps the samples will be incubated with calcium ionophore A23187 and dimethyl sulfoxide and analysed in interdiferencial contrast microscope, fluorescênia (for cytoskeleton - microtubules) and electronic transmission. The sperm ultrastructure and the acrosome reaction will be processed for routine in Epon-Araldite resin. Since the Dromiidae belong to brachyuran, it is expected that the reproductive system show the standard pattern of regionalization following the usual description to crabs, being the sperm packed in coenospermic spermatophores. Additionally, we expect that H. parasitica shows the acrosome reaction and transfer sperm similar to other brachyuran with espermatheca performing storage site of sperm. The espermiotaxonomy will provide features to elucidate the relationships among the subfamilies of Dromiidae and also to other Podotremata families and superfamilies. (AU)