Reproductive biology of Hemidactylus agrius (Vanzolini, 1978) in the Caatinga of Paraíba, Brazil

Abstract

This study evaluated the influence of somatic indices and climatic variables on the gametogenesis of Hemidactylus agrius in a semi-arid Caatinga population, north-eastern Brazil. A total of 61 specimens were collected during monthly field surveys conducted between July 2023 and June 2024. Reproductive dynamics were assessed through histological analyses and the calculation of body condition (K1), gonadosomatic (RLG) and hepatosomatic (RLW) indices in relation to environmental variables. Morphometric data revealed clear sexual dimorphism, with females displaying a lagrer body size and higher K1 and RLW values, suggesting greater energetic investment in reproduction. Histological evidence showed the presence of all stages of the germ cell lineage in reproductively active individuals throughout the year, supporting continuous gametogenic activity. Somatic indices showed low temporal variation, and precipitation was not significantly correlated with reproductive parameters. In contrast, temperature exerted a significant negative effect on both RLG and RLW, suggesting that increased metabolic demands under warmer conditions may modulate reproductive intensity. These findings indicate that H. agrius maintains year-round reproductive activity with low seasonality. This pattern is consistent with life-history strategies in semi-arid environments, where environmental unpredictability may favour continuous reproductive readiness. Keywords: gonadosomatic index, hepatosomatic index, histology, reproductive cycles, lizards