Feeding Habits and Reproductive Biology of Australian Pygopodid Lizards of the Genus Aprasia

Abstract

We dissected 615 preserved specimens of eight species of wormlike burrowing pygopodid lizards of the genus Aprasia, to document the basic natural history of this poorly known Australian taxon. Females grow larger than males but are less common in museum collections. At least four species were found to be oviparous, with each female producing two eggs per clutch. Reproductive cycles of both sexes are highly seasonal in A. pulchella and A. repens (with oviposition in summer) but apparently aseasonal in A. striolata. The diet of Aprasia consists almost entirely (>95%) of the larvae and pupae of ants of several genera. Aprasia consume large numbers of prey items in a single meal but may feed only infrequently and only in warmer months of the year. Larger A. repens consumed larger prey, but there was no evidence of sex-based differences in prey type or prey size despite the presence of significant dentitional dimorphism in this species. Overall, our data emphasizes the remarkable diversity of dietary habits within the pygopodid lizards, especially relative to the general conservatism of other gekkotan lizards in this regard. In several significant features of their morphology and trophic ecology, Aprasia are more similar to sympatric typhlopid snakes than they are to confamilial lizards.