Dietary analysis of Homonota darwini (Squamata:Gekkonidae) in Northern Patagonia

【摘要】：正 Our study investigated the diet of the southernmost gecko in the world, Homonota darwini. Fifty-three specimenswere captured during spring and summer in four locations in Patagonia, Argentina. The stomach contents of the specimens wereidentified, and we found that prey consisted of six main groups: Coleoptera, Hymenoptera, Homoptera and Araneae, and theadults and larvae of moth Lepidoptera. Lepidoptera was the major dietary component. The presence of ants and moths as commonprey suggests an ambush feeding strategy. In spring, females consumed more ants than males although no other dietary differencesbetween males and females were evident. We found nine geckos with empty stomachs and six parasitized by nematodes.Presence of empty stomachs corroborates previous observations of other nocturnal geckos and non-gecko lizards. Reduced foragingsuccess of nocturnal lizards could be due to difficulty in prey detection due to dim light, reduced or erratic activity of insectprey at night, or shorter activity times of geckos relative to diurnal success. Sex and season were not associated with the incidenceof empty stomachs. Principal component analysis showed that four food alternatives correlated with season. The constraint ofnocturnality, coupled with low night-time temperatures restricting feeding to only a few hours after sunset, appear to have causeda generality of diet which may limit energy acquisition. We conclude that H. darwini is an arthropod generalist and likely an ambushforager, as are many other nocturnal gekkonids