Reproductive phenology of neotropical leptodactylid frogs (genera Physalaemus and Pseudopaludicola): Integrating gametogenic cycle, sexual maturity and age

Abstract

Ontogeny, temporal strategies and the reproductive cycle are basic aspects of a species' life history and can provide us with information about the current status and future trends of a population. Here, we present data on reproductive biology, influence of environmental factors on male and female reproductive parameters and intra- and interspecific comparisons regarding these parameters, as well as unpublished data on age at sexual maturity and longevity of the syntopic and phylogenetically close frogs Physalaemus cuvieri – dog frog –, Physalaemus riograndensis – Rio Grande frog – and Pseudopaludicola falcipes – Hensel's swamp frog –, in southern Brazil. Accordingly, we used morphoanatomical and histological analyses, whose results were associated with climatological environmental variables (temperature, rainfall, relative humidity and photoperiod). Our results indicate that although they are phylogenetically close and that they co-occur in reproductive environments, the species differ in terms of reproductive cycle and in how environmental variables affect reproductive parameters between the sexes: photoperiod was the most important environmental factor for males and females of P. falcipes, while air humidity was more important for P. cuvieri. The age aspects also varied between the species, where sexual maturity was reached later in the Physalaemus species and the greatest longevity recorded for P. cuvieri. In addition, we found that there was intersexual and interspecific variation in the patterns measured, reflecting intrinsic differences in reproductive strategies and modes. Such studies are of paramount importance, as they serve as a basis for further research, in addition to allowing comparisons and/or possible generalizations about the evolutionary meaning of reproductive strategies.