Use of cacti as heat sources by thermoregulating Mabuya agilis (Raddi) and Mabuya macrorhyncha Hoge (Lacertflia, Scincidae) in two restinga habitats in southeastern Brazil

• Autor(a) principal: Vrcibradic,Davor
• Data de Publicação: 2002
• Outros Autores: Rocha,Carlos Frederico Duarte
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Revista Brasileira de Zoologia (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752002000100005
• topic: Mabuya; lizard; thermoregulation; cacti; heat gain by conduction; restinga habitat; Southeast Brazil

Lizards may benefit from gain of heat from contact with the substrate via conduction. In this study, evidence that the lizards Mabuya agilis (Raddi, 1823) and Mabuya macrorhynclui Hoge, 1946 (Scincidae) inhabiting two restinga habitats in southeastern Brazil (Grussaf, Rio de Janeiro and Praia das Neves, Espfrito Santo), may shift microhabitat preferences along the day, and that such shifts may be related to the use of cacti surfaces as direct sources of heat is presented. For both species, body temperature (Tb) was always significantly correlated (p < 0,05) with air temperature (Ta). Tb was significantly correlated (p < 0,0.5) with substrate temperature (Ts) for M. agilis collected on cacti, but not for specimens collected on the ground. For M. macrorhyncha collected on cacti, both Ta and Ts were more important in conjunction than separately, in explaining lizard Tb. Use of cacti as perches by M. agilis was more frequent during late afternoon when environmental temperatures are declining, but such a trend was not evident for M. macrorhynclui. We suggest that the use of cacti as direct heat sources may be more evident in the ground-dwelling M. agilis than in the scansorial M. macrorhynclui.