COMPARATIVE METABOLIC RATE-TEMPERATURE CURVES OF PHRYNOCEPHALUS-ARABICUS ANDERSON, 1894 AND AGAMA [STELLIO] STELLIO BRACHYDACTYLA HASS, 1951 (AGAMIDAE, SAURIA, REPTILIA)

Resting oxygen consumption (VO2) rates of two desert agamid lizards, P hrynocephalus arabicus and Agama [Stellio] stellio brachydactyla, were determined in relation to ambient temperatures ranging from 10 to 40- degrees-C using a double-chambered, volumetric, closed system. Both sp ecies show relatively similar activity and preferred body temperature (PBT) ranges. Thermal dependence co-efficient (Q10) value shifts refle ct that A. s. brachydactyla has a slightly lower mean PBT than that of P. arabicus. However, the metabolic rate-temperature (M-T) curves dis play the enhanced body mass-specific VO2 compared with the resultant o bscured effect of the cooler microhabitats that A. s. brachydactyla se eks and adapts to.