We describe two new aspects of male reproduction in the pit viper Bothrops cotiara: the formation of mating plugs and epididymal sperm storage. Based on histological analyses of specimens (four males and three females), we propose that long-term sperm storage occurs in the ductus deferens, whereas macroscopic hypertrophy indicates that the epididymis may be a short-term sperm storage site. Secretions of the sexual segment of the kidneys probably form the mating plug that males deposit in the female vagina during copulation. A mating plug without sperm was observed in the spring. Future studies should address the functions and longevity of mating plugs and the role of the epididymis in Bothrops reproduction.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Sao Paulo State Univ UNESP, Anim Biol Postgrad Programme, Sao Jose Do Rio Preto, SP, BrazilButantan Inst, Lab Ecol & Evolut, Sao Paulo, SP, BrazilUniv Fed Sao Paulo UNIFESP, Dept Expt Neurol, Sao Paulo, SP, BrazilUniversidade Federal de São Paulo (UNIFESP), Dept Expt Neurol, Sao Paulo, SP, BrazilFAPESP: 2012/15037-4Web of Scienc
