Testosterone Cycle and Regulation of Reproductive Events in the LizardPhymaturus punae(Liolaemidae) from the Highlands of the Andes, Argentina

Abstract

Abstract The genus Phymaturus, entirely viviparous and mostly herbivorous, inhabits the cold and harsh environments of the Andean highlands of Argentina and Chile, and the Patagonian steppe of Argentina. Phymaturus punae is a vulnerable lizard endemic to the Biosphere Reserve San Guillermo (National Park and Provincial Reserve) in San Juan (Argentina) that inhabits high altitudes of 3,100–4,200 m. The reproductive cycles of males and females of P. punae have been described previously. Males perform a prenuptial and annual cycle of spermatogenesis, and females reproduce once every 2 yr. As a consequence, the adjustment in the timing of males to the reproductive cycles of females must be very precise to ensure reproductive success. We elucidate the time of mating and the asynchrony of male and female reproductive events in P. punae based on endocrine and ultrastructural studies. Present hormonal results support the idea that copulation in P. punae occurs at the end of the activity season. Ultrastructural fe...