Female Reproductive Cycles of Five Species of Snakes (Reptilia: Colubridae) from the Yucatan Peninsula, Mexico

Abstract

Female reproductive cycles were studied in five species of colubrid snakes from the Yucatan Peninsula, Mexico (Dryadophis melanolomuis, Elaphe triaspis, Leptophis mexicanus, Oxybelis aeneus, and Stenorrhina freminvillii). Leptophis mexicanus and Oxybelis aeneus reproduce annually during the rainy season (March-October and March-August, respectively). Dryadophis melanolomus also reproduces during the rainy season, but has a biennial cycle. Stenorrhina freminvillii lays two clutches of eggs annually during the dry season (November-April). Elaphe triaspis appears to have aseasonal (continuous) reproduction. Clutch size varies from x = 3.1 eggs (D. melanolomus) to x = 11.6 eggs (S. freminvillii). The timing of reproductive cydes of these species is compared with the climatic regime of the Yucatan Peninsula, and the significance of adaptation of reproductive cydes to geographic distribution and dispersal is discussed.