Thermal ecology and microhabitat use by lizards are affected directly and indirectly by intrinsic (e.g., sex and body size) and extrinsic (e.g., environmental seasonality, vegetation cover, and wind speed) factors. Herein we evaluate the effect of seasonality and sex on field thermal ecology and microhabitat utilization of a population of Anolis carlliebi inhabiting a xeric scrubland in Central Mexico. Lizards were found primarily in full and filtered sun conditions, strongly associated, respectively, with inflorescences and leaves of Agave stricta. Males were slightly larger than females. Mean field body temperature did not differ between sexes within seasons, but males used higher perches than females in the warm season. We observed a seasonal shift in body temperature and perch use in males, which exhibited higher body temperatures and occupied wider and higher perches in the warm season. Female body temperature and perch use did not differ between seasons. This study reports the first case of a population of Anolis specializing in a species of Agave as microhabitat. These results add to our understanding of thermoregulation and microhabitat use of mainland species of Anolis since they face different environmental pressures than Caribbean species.