New dietary records and geographic variation in the diet composition of the snake Philodryas nattereri in Brazil

Regional data on the natural history of snakes are important for understanding patterns of ecological geographic variation of widely distributed species. In this study, we report new dietary data about the South American dipsadine snake Philodryas nattereri in the Caatinga and Atlantic Forest regions of northeastern Brazil. Our observations in the wild include predation on large-sized lizards (Iguana iguana), adult birds (Columbina picui), venomous toads (Rhinella jimi and R. granulosa), snakes (Lygophis dilepis), bird chicks inside nests (C. picui, Tangara sayaca and Troglodytes musculus), nocturnal-crepuscular terrestrial mammals (Galea spixii) and strictly nocturnal flying mammals (Artibeus planirostris). Besides bringing new data about feeding habits of P. nattereri, we also compare its diet composition between the Caatinga and the Cerrado, the Brazilian ecoregions that are part of the South American dry diagonal, by pooling our original data with all available literature records. The diet composition of P. nattereri is significantly different between these two regions: lizards comprise the predominant prey category for P. nattereri in the Caatinga (57.6 %), whereas mammals stand out as the most reported prey category in the Cerrado (67.2 %). Our results evidence generalist and opportunistic feeding habits of P. nattereri, one of the most common snake species in non-strictly forest ecosystems of Brazil.