Life in the Grasses: The Autecology of the Whiptail Lizard Ameivula ocellifera from a Savanna Enclave in the Atlantic Forest of Northeastern Brazil

Understanding a species' natural history is fundamental for identifying patterns and enabling ecological and evolutionary comparisons. We investigated the autecology of the heliophilous, actively foraging whiptail lizard Ameivula ocellifera in a Neotropical savanna enclave in within the Atlantic Forest of northeastern Brazil. Lizards were active during the hottest hours of the day and were primarily associated with grassy areas on sandy soil. Body temperatures were relatively high (mean: 37.8°C) and positively correlated with both substrate and air temperatures, consistent with observations in other populations of the species. Ameivula ocellifera fed mainly on orthopterans, spiders, and insect larvae, similar to other teiid lizards. Sexual dimorphism was evident, with males being larger and having taller heads, while females had longer bodies, a trait typically linked to reproductive investment. Clutch size averaged 1.89 eggs (n = 1–4), but no correlation was found between clutch size and female snout–vent length. Reproductive males were observed year-round, whereas reproductive females were only found during the dry season, suggesting that females regulate the reproductive cycle. Reproduction occurred primarily during the dry season and followed a bimodal pattern, with recruitment also bimodal and concentrated at the onset of the wet season. These reproductive and recruitment patterns may be shaped by the environmental characteristics of Tabuleiro savannas. While our findings support the notion of niche conservatism in several ecological aspects of A. ocellifera, they also highlight how local environmental factors can significantly influence the ecology—particularly diet and reproduction—of some populations.