THERMAL PHYSIOLOGY OF THE INVASIVE TROPICAL HOUSE GECKO, HEMIDAcTyLUs MABOUIA (SQUAMATA, GEKKONIDAE)

Thermal physiological traits are ecologically important to ectotherms and seem to be under natural selection in lizards. Therefore, thermal physiology studies are particularly helpful in understanding biological invasions and may provide insights into what makes an invader successful and distribution patterns. Among invasive vertebrates, the Tropical House Gecko (Hemidactylus mabouia) is noticeable for being an extremely successful invader that colonized a wide range of habitats with different climatic conditions. We described the T-pref, CTmin, CTmax, and thermal tolerance of an urban population of H. mabouia in the Cerrado savanna region of Brazil and tested for differences between sexes and ontogenetic stages. Juvenile H. mabouia exhibited higher CTmin, lower CTmax, and a narrower thermal tolerance range than adults. This result could be explained by the effects of body size in the thermoregulation capacity or related with differences in microhabitat usage. We also tested two methods to measure body temperature: a thermocouple sensor inserted in the cloaca versus in the abdomen surface. Our study provides new information regarding the thermal physiology of H. mabouia and a detailed methodology for handling these geckos in the laboratory and measuring thermal physiology traits, which will be useful for future studies in this species.