title: Testicular structure and spermatogenesis of Amazonian freshwater cururu stingray Potamotrygon cf. histrix.
abstract: The cururu stingray Potamotrygon cf. histrix, a new and endemic Amazonian freshwater species, presents appropriate characteristics for fish keeping and is exploited from its natural environment. The present study identified the testicular structure and spermatogenesis of this species. Gonads from adult male specimens were dissected, fixed and processed for histological analysis. The testes were of testicular/epigonial type. The presence of germinal papillae was observed in the upper portion of organ with primordial germ cells and Sertoli cell precursors. The testis was lobular with zonal organization and cystic gametogenesis, with the occurrence of spermatoblasts. The Sertoli cells underwent morphological modifications over the course of gamete formation. The spermatozoids had long heads and were spiraled on their own axis. Information on the reproductive biology will serve as basis for studies on the reproduction and phylogeny of this peculiar group of cartilaginous fish.
authors: Department of Biology, University of Rio Verde - FESURV, Campus Universitário, s/n. Rio Verde, Goiás, CEP: 75901-970. Brazil. sfzaiden@hotmail.com
authors: Sérgio Fonseca
authors: SF
authors: Zaiden
authors: Richard Phillip
authors: RP
authors: Brinn
authors: Jaydione Luiz
authors: JL
authors: Marcon
authors: Elisabeth Criscuolo
authors: EC
authors: Urbinati
mesh_terms: D000818:Animals; D005618:Fresh Water; D008297:Male; D012708:Sertoli Cells / Q000166:cytology*; D012860:Skates, Fish; D013087:Spermatids / Q000166:cytology* / Q000648:ultrastructure; D013091:Spermatogenesis / Q000502:physiology*; D013737:Testis / Q000166:cytology* / Q000648:ultrastructure*