On the natural history of the Caatinga Horned Frog, Ceratophrys joazeirensis (Anura: Ceratophryidae), a poorly known species of northeastern Brazil

Data on reproduction, sexual dimorphism, and the diet of Ceratophlys joazeirensis, the only species of the genus that occurs in the Brazilian semiarid Caatinga Biome, are presented. Anurans were observed and collected in Santa Maria Municipality, state of Rio Grande do Norte in northeastern Brazil. Fieldwork was conducted at night either after or during rains throughout the rainy season in 2010-2013. Searches were conducted near places where males were calling, usually around the perimeters of bodies of water. Reproduction is explosive in the population, with breeding activity occurring as the rain intensified during the rainy seasons of 2011-2013. However, in 2010, neither calling males nor active females were found, even after rainy days. Although males call in temporary and permanent ponds, most males call in the marginal vegetation of temporary ponds. Females C. joazeirensis are significantly larger than males. The average clutch size is 2555.0 +/- 1551.1 eggs; clutch size is not significantly correlated with female body size. In decreasing order of volume, the most important prey categories in the diet of C. joazeirensis are anurans, followed by coleopterans and plant material. The apparent importance of anurans in the diet probably is related to the number of anuran species that co-occur with C. joazeirensis and the voracious feeding behavior of ceratophryids.