Ciclo reprodutivo, dimorfismo sexual e anatomia do sistema reprodutor da jararaca Bothrops leucurus (Wagler, 1824) (Squamata: Viperidae) na área de proteção ambiental do Catolé e Fernão Velho, um remanescente de Mata Atlântica no estado de Alagoas

Abstract

The reproductive biology of snakes is an essential field for understanding adaptive strategies, seasonal cycles and morphological patterns associated with reproduction. Bothrops leucurus, belonging to the subfamily Crotalinae (Viperidae), is a venomous snake endemic to Brazil, widely distributed in the Northeast, where it acts as an important predator and is responsible for most of the snakebites recorded in the region. Despite its medical and ecological importance, studies on its reproductive biology are still scarce. In this study, the reproductive biology of Bothrops leucurus was analyzed using 53 individuals from the MHN-UFAL scientific collection, focusing on morphological, seasonal and sexual patterns. The specimens were collected in the Catolé and Fernão Velho Environmental Protection Area (APACFV), in Alagoas. The results revealed marked sexual dimorphism, with females showing greater snout-vent length (SVL) and males showing proportionally longer tails. Reproductive activity was seasonal, concentrated in the months with the highest rainfall. In males, individuals with a coiled vas deferens (indicative of active spermatogenesis) were recorded preferentially during the rainy season, and there was a positive correlation between testicular volume and SVL. In the females, there was progressive follicular development between June and August, with the occurrence of follicles in secondary vitellogenesis and eggs in the oviducts; the average estimated clutch size was 27 ± 7. Cases of follicular atresia were observed even during the active reproductive period. Environmental humidity apparently acts as a physiological factor modulating the reproductive cycle of the species, indicating an adaptation to the seasonal climate of the northeastern Atlantic Forest. The data obtained corroborates the patterns of seasonality of reproductive activity, sexual dimorphism and litter size known for the genus, highlighting phylogenetic conservation in the clade and offering support for management and conservation actions in fragmented areas under intense anthropic pressure.