Características de la espermatogénesis en una serpiente endémica de Cuba: Caraiba andreae andreae (Squamata: Dipsadidae) / Characteristics of the spermatogenesis on a Cuban endemic snake: Caraiba andreae andreae (Squamata: Dipsadidae)

Resumen Caraiba andreae andreae es una serpiente abundante y exclusiva de Cuba. Se desconocen aspectos de su biologia reproductiva y de sus celulas sexuales, por lo cual el objetivo de este trabajo fue caracterizar su espermatogenesis. Se colectaron cinco machos durante el verano, en la region occidental del pais. Se extrajeron las gonadas y sus fragmentos se procesaron mediante tecnicas de histologia clasica y Microscopia Electronica de Transmision. Se detecto que todos estaban espermatogenicos. En los tubulos seminiferos habia celulas de Sertoli y, asociadas a estas, estaban las celulas espermatogenas y los espermatozoides dispuestos en disposicion radial.  Se describieron espermatogonias de tipo A y B, espermatocitos primarios y secundarios, asi como espermatidas en diferentes grados de diferenciacion. El espermatozoide mostro la cabeza alargada y conica, acorde al acrosoma. Al Microscopio Electronico de Transmision el nucleo tiene un rostrum y la cromatina compactada. Se observaron hasta 10 mitocondrias. Los resultados relativos a la ultraestructura de los espermatozoides en reptiles, pueden tener implicaciones filogeneticas. ABSTRACT Caraiba andreae andreae is an abundant and exclusive snake from Cuba. Aspects of its reproductive biology and sexual cells are unknown, so the aim of this research was to characterize its spermatogenesis. Five males were collected during the summer, in the western region of the country. The gonads were extracted and its fragments were processed by classical histology and Transmission Electron Microscopy techniques. As a result, it was detected that all were spermatogenic. In the seminiferous tubules there were Sertoli cells and, associated with these, were the spermatogenic cells and the sperm arranged in radial arrangement. Spermatogonias of type A and B, primary and secondary spermatocytes and spermatids in different degrees of differentiation were described. The spermatozoon showed the elongated and conical head, according to the acrosome. At the Transmission Electron Microscope the nucleus has a rostrum and compacted chromatin. Up to 10 mitochondria were observed. The results regarding the ultrastructure of sperm in reptiles may have phylogenetic implications.