The tadpole of Odontophrynus monachus Caramaschi & Napoli, 2012 (Amphibia, Anura: Odontophrynidae).

The genus Odontophrynus Reinhardt & Lütken comprises 11 species distributed throughout South and East of South America (Frost 2016) clustered in three phenetic groups: O. americanus, O. cultripes, and O. occidentalis (Savage & Cei 1965; Cei 1987; Caramaschi & Napoli 2012). Only the O. occidentalis group is recovered as monophyletic in the most recent phylogenetic hypotheses (Pyron & Wiens 2011; Pyron 2014). In these analyses, the O. cultripes group is not recovered and the monophyly of O. americanus group was not tested, since only one species of the group was included (Pyron & Wiens 2011; Pyron 2014). Therefore, the relationships within the genus are still inconclusive due to low support values and limited taxon sampling.

A new species of Hatchet-faced Treefrog Sphaenorhynchus Tschudi (Anura: Hylidae) from Quadrilátero Ferrífero, Minas Gerais, southeastern Brazil.

A new species of Sphaenorhynchus is described from the Municipality of Mariana, State of Minas Gerais, Brazil. It is characterized by the vocal sac moderately developed, single, subgular, with longitudinal folds; white canthal and dorsolateral lines delimited below by a dorsolateral black line from the tip of snout extending beyond the eye to gradually disappearing up to the flanks; and premaxilla and maxilla almost completely edentulous, each bearing 1-5 extremely small teeth. It is most similar with Sphaenorhynchus orophilus, from which it can be distinguished by having a less robust forearm in males; glandular subcloacal dermal fold; premaxilla and maxilla almost completely edentulous; and larvae with large marginal papillae in the oral disc. The new species occurs in natural ponds over ironstone outcrops (known as canga) on flat terrain, where males call from the floating vegetation.

Differential effects of temperature on the feeding kinematics of the tadpoles of two sympatric anuran species.

Temperature impacts ectotherm performance by influencing many biochemical and physiological processes. When well adapted to their environment, ectotherms should perform most efficiently at the temperatures they most commonly encounter. In the present study, we tested how differences in temperature affects the feeding kinematics of tadpoles of two anuran species: the benthic tadpole of Rhinella schneideri and the nektonic tadpole of Trachycephalus typhonius. Benthic and nektonic tadpoles have segregated distributions within ponds and thus tend to face different environmental conditions, such as temperature. Muscle contractile dynamics, and thus whole organism performance, is primarily temperature dependent for ectotherms. We hypothesized that changes in mean temperatures would have differential effects on the feeding kinematics of these two species. We conducted a laboratory experiment in which we used high-speed videography to record tadpoles foraging at cold and warm temperatures. In general, tadpoles filmed at warm temperatures opened their jaws faster, attained maximum gape earlier, and exhibited shorter gape cycles than tadpoles in cold temperatures, irrespective of species. We also found species x temperature interactions regarding the closing phase velocity, and the percentage of time it takes tadpoles to achieve maximum gape and to start closing their jaws. These interactions could indicate that these two co-occurring species differ in their sensitivity to differences in water temperature and have temperature-dependent feeding strategies that maximize feeding performance in their preferred environment.