Physalaemus henselii

Abstract: Physalaemus henselii (Peters, 1872) is a little known leiuperid frog that has not been studied since the 1960’s. Herein, we redescribe its advertisement call, and assess the female sexual cycle and the reproductive period on the basis of the macroscopic analysis of the ovaries and field observations. The Ovarian Size Factor (OSF) was calculated. The study was made in Departamento de Rivera, northern Uruguay. The advertisement call consists of short (177 ± 21ms), multipulsed (20 ± 3 pulses/note) notes, with a note repetition rate of 1.57 ± 0.13 notes/s. Physalaemus henselii has a female sexual cycle with unimodal distribution of gravid females, which are present from February to September. The OSF and the ratio "females with mature oocytes / females without mature oocytes" reached the highest values from April to June. The number and size of oocytes were positively correlated with female size. The smallest female (SVL =18.94mm, weight =0.78g) with mature oocytes was found in July. The observed sexual cycle with a single annual reproductive period during the cold season (autumn and early winter), is an uncommon fact for anuran species in the region.

Abstract: In this work, we studied chromosome morphology, Ag-NOR, and C-banding patterns in the Neotropical leiuperid frogs that compose the Physalaemus henselii species group: Physalaemus fernandezae, Physalaemus henselii, and Physalaemus riograndensis. The chromosome diploid complement in all species was 2n = 22 and consisted of seven large to medium and four small chromosome pairs. Chromosome fundamental number (FN) varied, because pair 11 was metacentric in P. henselii and P. riograndensis (FN = 44) but telocentric in P. fernandezae (FN = 42). Each species presented a single pair of Ag-NORs, which are located in the secondary constriction of pair 11 in the case of P. fernandezae, in pair 8 in P. riograndensis (as in many other Physalaemus species), and in pair 5 in P. henselii, which is a unique character state among leiuperids. There were no substantial interspecific differences in C-banding pattern, and the heterochromatic bands were mainly located in the centromeric regions of all chromosomes....

Abstract: Although Physalaemus frogs are prominent members of Neotropical herpetofauna, larval stages are not known from more than half of the species in this genus. Herein, we describe the tadpole of Physalaemus henselii based on samples collected in Departamento de Rivera, northern Uruguay. General aspect and major external morphological features are similar to most of other known tadpoles of Physalaemus. Remarkable character states are a medial vent tube and the presence of dorsal and ventral gaps in the row of marginal oral papillae. Physalaemus henselii has been successively assigned to the P. cuvieri and to the P. henselii species groups, but no conclusions can be drawn in support of these associations from external larval morphology. Instead, we found that some character states may contribute to relate species, like the presence of a ventral gap in the marginal row of oral papillae which is shared by P. albonotatus, P. cuqui, P. cuvieri, P. fernandezae and P. henselii. This character state is unique among non-bufonid anurans, although it is also present in some species of the related genus Pseudopaludicola. In addition, P. albonotatus, P. cuqui and P. cuvieri tadpoles can be differentiated from P. fernandezae and P. henselii by the presence of two small ventrolateral gaps, which are absent in the latter.

Abstract: Considering that habitat use by amphibians is related both with climate and environmental features, we tested the hypothesis that anuran assemblages found in different phytophysiognomies and in different seasons vary in structure. Additionally, we searched for species which can be indicators of habitat and seasons. The study was conducted in the Pampa biome, southern Brazil. Sampling was done through pitfall traps placed in three phytophysiognomies: grassland, ecotone grassland/forest; and forest. The seasonality factor was created by grouping months in warn and cold seasons. Sixteen species were found and the assemblages were influenced both by phytophysiognomies and climatic seasonality. In a paired comparison, the three phytophysiognomies differed in structure of assemblage from each other. Physalaemus henselii, P. riograndensis, Pseudopaludicola falcipes and Pseudis minuta were indicators of ecotone. Leptodactylus gracilis and Physalaemus biligonigerus were indicators of grassland. None species was indicator of forest. Most of the species were indicators of warm season: Elachistocleis bicolor, Leptodactylus fuscus, L. gracilis, L. latinasus, L. latrans, L. mystacinus, Physalaemus biligonigerus, P. cuvieri and Pseudis minuta. None species was indicator of cold season. We found that even for species of open areas, as Pampa, heterogeneous phytophysiognomies are important for maintaining abundance and constancy of populations of anuran.