Thermal ecophysiology of Basiliscus galeritus (Squamata: Corytophanidae) in two populations at different altitudes: Does the crest participate actively in thermoregulation?

Thermoregulation is a critical process for ectotherms as non-avian reptiles, since their vital physiological processes depend on it. These organisms have a temperature range where their physiological processes are more efficient, this range is usually a requirement set phylogenetically even though they vary in the use of habitats. This research compares the thermal ecophysiology of Basiliscus galeritus (western basilisk) in two populations with altitudinal differences in the northwestern of Ecuador. The results suggest that the difference of altitude between the two locations (500 m) influences the thermal ecophysiology of the species since the body temperature (Tb), operative temperature (Te) and preferred body temperature (Tset) showed significative differences. Furthermore, B. galeritus obtains its Tb through heliothermy and it behaves as an active thermoregulator. On the other hand, the crest temperatures reach higher values than their Tset, the results suggested that the species uses the crest as an alternative to regulate its body temperature when exceeding its Tset. Besides, this thermoregulatory behavior has been suggested only in some extinct synapsids.