Diogo B. Provete

Is rich and rare the common share? Describing biodiversity patterns to inform conservation practices for South American anurans.

Species richness and range size are key features of biogeographic and macroecological analyses, which can yield a first assessment tool to define conservation priorities. Here we combined both features in a simultaneous analysis, based on range-diversity plots, to identify sets of rich-rare (high species richness with restricted ranges) and poor-rare cells (low species richness with restricted ranges). We applied this analysis to the anurans of South America and evaluated the representation of those sets of cells within the protected area system. South American anurans showed high species richness in the Brazilian Atlantic Forest and East Tropical Andes, while regions harboring most of the rare species were concentrated in the Andes and Atlantic Coast from North-Eastern Brazil to River Plate. Based on such patterns, we identified as rich-rare cells the Brazilian Atlantic Forest and Tropical Andes and as poor-rare cells the southern part of Andes and Uruguay. A low fraction of both sets of cells was represented within the protected area system. We show that a simultaneous consideration of species richness and rarity provides a rapid assessment of large-scale biodiversity patterns and may contribute to the definition of conservation priorities.

Broad-scale spatial patterns of canopy cover and pond morphology affect the structure of a Neotropical amphibian metacommunity

Spatial and environmental processes influence species composition at distinct scales. Previous studies suggested that the distribution of larval anurans at the landscape-scale is influenced by environmental gradients related to adult breeding site selection, such as pond canopy cover, but not by water chemistry. However, the combined effects of spatial, pond morphology, and water chemistry variables on metacommunity structure of larval anurans have not been analyzed yet. We used a partial redundancy analysis with variation partitioning to analyze the relative influence of pond morphology (e.g., depth, area, and aquatic vegetation), water chemistry, and spatial variables on a tadpole metacommunity from southeastern Brazil. We predict that pond morphology and canopy cover will influence the metacommunity at broad spatial scales, while water chemistry would play a larger role at finer scales. We found that broad-scale spatial patterns of pond canopy cover and pond morphology strongly influenced metacommunity structure, with water chemistry being not significant. Additionally, species composition was spatially autocorrelated at short distances. We suggest that the reproductive behavior of adult anurans is driving tadpole metacommunity dynamics, since pond morphology, but not water chemistry affects breeding site selection by adults. Our results contribute to the understanding of amphibian species diversity in tropical wetlands.

Redescription of Physalaemus barrioi (Anura: Leiuperidae)

Physalaemus barrioi is a poorly known frog endemic to the highlands of Serra da Bocaina in the Atlantic Forest of southeastern Brazil. Herein, we redescribe the species based on the type series and new specimens collected at the type locality. We also present additional data on its vocalization, karyotype, and tadpole, including the external morphology, internal oral features, and chondrocranium. Physalaemus barrioi can be diagnosed by the following combination of characters: SVL in males larger than 24 mm; inguinal glands associated with dark ocelli; throat and vocal sac dark brown; and chest dark with small light blotches. Bioacoustical characteristics also distinguish P. barrioi from all other species of Physalaemus. The tadpole of P. barrioi is very similar to those of the P. gracilis group, from which it can be distinguished by several characteristics, including marginal papillae in a single row, absence of submarginal papillae, elliptical nares, and upper jaw sheath in a wide arch.

Phylogenetic signal and variation of visceral pigmentation in eight anuran families

Provete, D. B, Franco‐Belussi, L., de Souza Santos, L. R., Zieri, R., Moresco, R. M., Martins, I. A., de Almeida, S. C., & de Oliveira, C. (2012). Phylogenetic signal and variation of visceral pigmentation in eight anuran families. —Zoologica Scripta, 41, 547‐556.

Phylogenetic patterns and the adaptive evolution of osmoregulation in fiddler crabs (Brachyura, Uca)

Salinity is the primary driver of osmoregulatory evolution in decapods, and may have influenced their diversification into different osmotic niches. In semi-terrestrial crabs, hyper-osmoregulatory ability favors sojourns into burrows and dilute media, and provides a safeguard against hemolymph dilution; hypo-osmoregulatory ability underlies emersion capability and a life more removed from water sources. However, most comparative studies have neglected the roles of the phylogenetic and environmental components of inter-specific physiological variation, hindering evaluation of phylogenetic patterns and the adaptive nature of osmoregulatory evolution. Semi-terrestrial fiddler crabs (Uca) inhabit fresh to hyper-saline waters, with species from the Americas occupying higher intertidal habitats than Indo-west Pacific species mainly found in the low intertidal zone. Here, we characterize numerous osmoregulatory traits in all ten fiddler crabs found along the Atlantic coast of Brazil, and we employ phylogenetic comparative methods using 24 species to test for: (i) similarities of osmoregulatory ability among closely related species; (ii) salinity as a driver of osmoregulatory evolution; (iii) correlation between salt uptake and secretion; and (iv) adaptive peaks in osmoregulatory ability in the high intertidal American lineages. Our findings reveal that osmoregulation in Uca exhibits strong phylogenetic patterns in salt uptake traits. Salinity does not correlate with hyper/hypo-regulatory abilities, but drives hemolymph osmolality at ambient salinities. Osmoregulatory traits have evolved towards three adaptive peaks, revealing a significant contribution of hyper/hypo-regulatory ability in the American clades. Thus, during the evolutionary history of fiddler crabs, salinity has driven some of the osmoregulatory transformations that underpin habitat diversification, although others are apparently constrained phylogenetically.

Anurans from the Serra da Bocaina National Park and surrounding buffer area, southeastern Brazil

Here, we review the species of anuran amphibian from the Serra da Bocaina National Park and its buffer area, in the Atlantic Forest of southeastern Brazil, comparing the data from a recent survey with museum records. We surveyed adult and larval anurans in ponds, marshes, and streams discontinuously from May 2008 to January 2011. In total, 63 anuran species were previously known to occur at the Park and its surrounding buffer area. In our survey, we recorded 46 species, of which five represented new records, and 22 appeared only in the historical list. Seven topotypic populations were not found in the present study. We suggest that conservation strategies for anurans in the Serra da Bocaina should also consider the surrounding areas that are subjected to anthropogenic pressure, due to the high diversity recorded, high altitudinal variation in species distribution, and various vegetation formations.

THE TADPOLE OF PHYSALAEMUS MOREIRAE (ANURA: LEIUPERIDAE)

Abstract We describe the external morphology of the tadpole of the frog Physalaemus moreirae. We also provide a review of internal oral features, chondrocrania, and a characterization of the genus based on larval traits. The internal oral features and the external morphology of P. moreirae are most similar to P. jordanensis, a species allocated to the P. gracilis group. None of the larval traits supports the current intrageneric arrangement of species, because several features are shared by species belonging to different species groups. We argue for the inclusion of larval traits in future phylogenetic studies in order to understand the evolution of larval characters.

Predators regulate prey species sorting and spatial distribution in microbial landscapes

The role of predation in determining the metacommunity assembly model of prey communities is understudied relative to that of interspecific competition among prey. Previous work on metacommunity dynamics of competing species has shown that sorting by habitat patch type and spatial patterning can be affected by disturbances. Microcosms offer a useful model system to test the effect of multi-trophic interactions and disturbance on metacommunity dynamics. Here, we investigated the potential role of predators in enhancing or disrupting sorting and spatial pattern among prey in experimental landscapes. We exposed multi-trophic protist microcosm landscapes with one predator, two competing prey, two patch resource types, and localized dispersal to three disturbance regimes (none, low, and high). Then, we used variation partitioning and spatial clustering analysis to analyse the results. In contrast with previous experiments that did not manipulate predators, we found that patch type did not structure prey communities very well. Instead, we found that it was the distribution of the predator that most strongly predicted the composition of the prey community. The predator impacted species sorting by (1) preferentially consuming one prey, thereby acting as a strong local environmental driver, and by (2) indirectly magnifying the impact of patch food resources on the less preferred prey. The predator also enhanced spatial signal in the prey community because of its limited dispersal. Our results indicate that predators can strongly influence prey species sorting and spatial patterning in metacommunities in ways that would otherwise be attributed to stochastic effects, such as dispersal limitation or demographic drift. Therefore, whenever possible, predators should be explicitly included as separate explanatory factors in variation partitioning analyses.

Larvae of Proceratophrys melanopogon (Amphibia: Anura), with Emphasis on Internal Oral Morphology and Comparisons with P. cururu and P. moratoi

Abstract: We provide novel data on the biology of Proceratophrys melanopogon and describe its larval external morphology and internal oral features on the basis of specimens from the Serra do Mar, southeastern Brazil. We also review the larval internal oral features of the genus, including descriptions and comparisons with P. cururu and P. moratoi. The external morphology of tadpoles of P. melanopogon is very similar to that of closely related species. The internal oral features are very conserved in this genus, with the majority of species having lingual papillae unusually bifurcated, four infralabial papillae, and a transverse ridge on the prenarial arena. Our results also provide data for phylogenetic studies on the genus Proceratophrys.

Response of digestive organs of Hypsiboas albopunctatus (Anura: Hylidae) to benzo[α]pyrene

Anurans are exposed to several pollutants. One of these is benzo[ α ]pyrene (BaP). This compound is produced by incomplete combustion and is toxic to the liver and intestine, where it is metabolized. Here, we tested how different concentrations of BaP affect the thickness of small intestine and liver melanomacrophages (MMCs) of Hypsiboas albopunctatus during short- and long-term exposures. We conducted an experiment with a 3 × 2 factorial design to answer these two questions. Male specimens were separated into groups injected with either 3 or 7 mg/kg of BaP and euthanized after either 72 or 168 h. Then, we measured the thickness of the intestinal epithelium and the area occupied by MMCs. The thickness of intestinal epithelium decreased in both high and low concentration for short-term exposure compared to control, and increased in the long-term group in both low and high concentrations. The short-term decrease in thickness is due to the damage caused by BaP on the absorptive capacity of the epithelium, whereas the epithelium increased its thickness and recovered normal activity in the long-term. High BaP concentration decreased the area of MMCs in the short-term group. The increase in MMCs is associated with the detoxifying role of these cells, while the decrease was triggered by cellular stress due to high BaP concentration. The concentrations of BaP we used are close to those found in polluted environments. Therefore, water contaminated with BaP can potentially affect the morphology of internal organs of anurans.