Reproductive biology and sexual dimorphism of a high-altitude population of the viviparous lizard Phymaturus punae from the Andes in Argentina

Abstract

Abstract Phymaturus punae is a viviparous lizard endemic to the Provincial Reserve San Guillermo, San Juan (Argentina). We present the first life history data of P. punae, belonging to an interesting genus adapted to cold climates. Females reach sexual maturity at 80.6 mm, and males at 84.4 mm snout-vent length. There is sexual dimorphism represented by larger and more robust males, but females show a wider body and a proportionally greater interlimb length than males. In males, spermatozoa become abundant in both testes and epididymi in mid-summer. Vitellogenic and pregnant females occurred simultaneously in late spring and mid-summer indicating a biennial reproductive cycle.