Breeding Phenology of Psammophilus dorsalis :Patterns in Time, Space and Morphology

Since reproduction is costly, animals are expected to invest in reproduction when abiotic and biotic conditions are optimal. Although tropical ecosystems are not as starkly seasonal as temperate ecosystems, some tropical ecosystems may experience high seasonality in conditions that affect reproduction. Systematic studies of breeding phenology from tropical ecosystems are scarce. We describe the breeding phenology of Psammophilus dorsalis, a sexually dimorphic, diurnal, rupicolous lizard found in the tropical scrub forests of peninsular India. Regular census was conducted covering multiple habitat patches for three years, recording age and breeding status of lizards. Lizards were systematically caught, tagged, measured and released. We report clear breeding seasonality, with most males showing breeding colouration from May to September and juveniles emerging from September until April. Timing of breeding coincides with the annual peak in daily maximum temperatures, while juvenile emergence might be affected by the timing of the annual precipitation peak. We report that this is a predominantly annual species with a female-biased sex ratio and strong male-biased dimorphism in multiple morphological traits. In the face of climate change, detailed studies of breeding phenology of tropical animals are important, particularly for ectotherms, since these taxa are easily affected by changes in temperature and precipitation patterns.