Intra-sex synchrony and inter-sex coordination in the reproductive timing of the Atlantic coral snake Micrurus corallinus (Elapidae) in Brazil

Dissection of preserved Atlantic coral snakes Micrurus corallinus, plus field data and histological analysis, provided information on male reproductive cycles. Testes are larger during autumn, when sperm production occurs, and smaller in spring, when spermatogenesis stops. The diameter of the distal deferent ducts is small in summer–autumn, when sperm are hardly found in the lumen, and it increases in winter–spring, when sperm is abundant, just prior to the mating season. Thus, the male cycle of M. corallinus is post-nuptial, whereas the female cycle is prenuptial. Although gametogenesis is not simultaneous in both sexes, the coordination of their cycles is guaranteed by sperm storage by males. Our data indicate that the diameter of the deferent duct is a good indication of the mating season, mainly when reproductive cycles are post-nuptial. Mate searching and aggregation occurs in the spring, and activity in both sexes may be highly related to their reproductive cycles.