Ecology of the lizard Norops oxylophus (Polychrotidae) in lowland forest of southeastern Nicaragua

Abstract

The lizard Norops oxylophus used a variety of microhabitats distributed linearly along streams in southeastern Nicaragua. Body temperatures averaged 27.8 °C and lizards typically were in shade. Lizards spent 98.16% of their time stationary and 1.84% moving. The rate of movement was low (0.001 m∙s−1) even when corrected for time not moving (0.071 m∙s−1). Caterpillars, spiders, ants, and various orthopterans composed most of the diet. Prey size was only weakly correlated with lizard snout–vent length (SVL) and there was no sexual difference in prey size independent of SVL. Lizards averaged 0.01 prey attacks/min and most lizards spent less than 0.15% of their time feeding. Males were larger than females, but females had a relatively larger body and greater mass. Females reach sexual maturity at 49 mm SVL and produce clutches of a single egg in rapid succession. Males reach sexual maturity at 53 mm SVL. Many ecological characteristics of N. oxylophus reflect a set of characteristics evolving early in the N. fuscoauratus series of the anoline lineage that has contributed to their ecological success in stream habitats of Caribbean lowland forest.