Reproductive system in Dromiidae: histochemical and ultrastructural characterization of spermatozoa and seminal fluid in Hypoconcha parasitica (Linnaeus, 1763)

Abstract

Studies on Hypoconcha parasitica are related to the external morphology, larval development and spatial distribution among other crabs. However there is no work on the reproductive system of Dromiidae, as well to Hypoconchinae sperm. Therefore, the aim of this study is describe the male reproductive system of H. parasitica and use sperm traits to understand the phylogenetic relations in Dromioidea. The specific aims are (1) testis classification and spermatogenesis description of this Podotremata; (2) histochemical characterization of seminal fluid and spermatophores development (if they are present) (3) describe spermatophores and sperm ultrastructure, in order to realize a comparative analysis of similarity with other species within available literature about Dromioidea. Mature males of H. parasitica will be collected by trawling at Ubatuba, SP, Brazil. For the histological and histochemical analysis, the reproductive system will be processed for historesin and stained with Hematoxylin and Eosin (H&E), and also stain techniques to neutral and acidic polysaccharides and for proteins. To sperm ultrastructure the samples will be processed according to routine for transmission electron microscopy in Epon-Araldite resin. It is expected that the reproductive system in Podotramata show a lobular type testis, which is widespread type of Brachyura. It is also expected that the sperm would be packaged into rounded spermatophores (coenospermics) typical of this Infraorder. Additionally, the sperm ultrastructure of Hypoconchinae could be raised some phylogenetic points in relation to Dromiidae and other Families of Dromioidea.