Thermal Effectiveness in Liolaemus riojanus and L. scapularis

Field data on thermal biology of two endemic especies of sand-dwelling lizards from northwestern Argentina.
Temperatures were measured in degrees Celsius.
The body temperatures (Tb), the air one centimeter from the substrate (Ta) and the substrate surface (Ts) were recorded with the same instrument (Reed LM 8000) at the time of capturing each specimen in the field.
The operating temperatures (Te) were recorded with dataloggers (ibuttons) distributed in the different microenvironments used by the lizards.
The preferred temperatures (Tsel) result from the average of the individual records of 65 animals transferred to the laboratory and maintained in a thermal gradient (20 to 60 ºC) for 4 hours.