47 research outputs found

    Structure and regional representativeness of the herpetofauna from Parque Estadual da Serra de Caldas Novas, Cerrado, Central Brazil

    Get PDF
    Amphibians and reptiles are diversified in the Cerrado biome but have been threatened by habitat loss and fragmentation, as well as lack of understanding of their distribution. Therefore, collection and organization of information about species in natural environments are essential for conservation, especially in Protected areas (PAs) and their adjacent zones. We present information about the composition and structure of the herpetofauna from Parque Estadual da Serra de Caldas Novas (PESCAN) and its representativeness in comparison to other PAs in the Cerrado. Fieldwork was conducted in 12 sampling sites from February 2009 to February 2010, using active search and pitfall traps. We recorded 41 species of amphibians, with greatest richness in sites with open vegetation and water bodies. Reptiles were represented by 32 species, with the greatest species richness in cerrado open environments. Both amphibian and reptile communities were more similar to those from geographically closer PAs and located in the central region of the Cerrado (State of Goiás and Distrito Federal). The PESCAN holds 24.85% and 17.98% of amphibians and reptiles species occurring in Cerrado PAs, respectivelly. This large representativeness and the high number of endemisms (18 amphibians and 7 reptiles) emphasize the importance of the PESCAN, together with other PAs, for the maintenance of regional biodiversity. In addition, we also encourage researches evaluating amphibian and reptile communities outside PAs, such as legal reserves, and we suggest new approaches to study the biodiversity of protected areas. © 2019, © 2019 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group

    Pigmentation plasticity enhances crypsis in larval newts: Associated metabolic cost and background choice behaviour

    Get PDF
    In heterogeneous environments, the capacity for colour change can be a valuable adaptation enhancing crypsis against predators. Alternatively, organisms might achieve concealment by evolving preferences for backgrounds that match their visual traits, thus avoiding the costs of plasticity. Here we examined the degree of plasticity in pigmentation of newt larvae (Lissotriton boscai) in relation to predation risk. Furthermore, we tested for associated metabolic costs and pigmentation-dependent background choice behaviour. Newt larvae expressed substantial changes in pigmentation so that light, high-reflecting environment induced depigmentation whereas dark, low-reflecting environment induced pigmentation in just three days of exposure. Induced pigmentation was completely reversible upon switching microhabitats. Predator cues, however, did not enhance cryptic phenotypes, suggesting that environmental albedo induces changes in pigmentation improving concealment regardless of the perceived predation risk. Metabolic rate was higher in heavily pigmented individuals from dark environments, indicating a high energetic requirement of pigmentation that could impose a constraint to larval camouflage in dim habitats. Finally, we found partial evidence for larvae selecting backgrounds matching their induced phenotypes. However, in the presence of predator cues, larvae increased the time spent in light environments, which may reflect a escape response towards shallow waters rather than an attempt at increasing crypsisFinancial support was provided by the Spanish Ministry of Science and Innovation (MICINN), Grant CGL2012-40044 to IGM, and by the Universidad Autónoma de Madrid, Short Stay Grant to NPC. Additional financial support was provided by the MICINN, Grant CGL2015-68670-R to NP

    The Population Decline and Extinction of Darwin's Frogs

    Get PDF
    Darwin's frogs (Rhinoderma darwinii and R. rufum) are two species of mouth-brooding frogs from Chile and Argentina. Here, we present evidence on the extent of declines, current distribution and conservation status of Rhinoderma spp.; including information on abundance, habitat and threats to extant Darwin's frog populations. All known archived Rhinoderma specimens were examined in museums in North America, Europe and South America. Extensive surveys were carried out throughout the historical ranges of R. rufum and R. darwinii from 2008 to 2012. Literature review and location data of 2,244 archived specimens were used to develop historical distribution maps for Rhinoderma spp. Based on records of sightings, optimal linear estimation was used to estimate whether R. rufum can be considered extinct. No extant R. rufum was found and our modelling inferred that this species became extinct in 1982 (95% CI, 1980-2000). Rhinoderma darwinii was found in 36 sites. All populations were within native forest and abundance was highest in Chiloé Island, when compared with Coast, Andes and South populations. Estimated population size and density (five populations) averaged 33.2 frogs/population (range, 10.2-56.3) and 14.9 frogs/100 m(2) (range, 5.3-74.1), respectively. Our results provide further evidence that R. rufum is extinct and indicate that R. darwinii has declined to a much greater degree than previously recognised. Although this species can still be found across a large part of its historical range, remaining populations are small and severely fragmented. Conservation efforts for R. darwinii should be stepped up and the species re-classified as Endangered

    Use and sharing of calling and retreat sites by Phyllodytes luteolus in a modified environment

    No full text
    I studied the use of calling and retreat sites by Phyllodytes luteolus in an ornamental bromeliad garden where phytotelmata in bromeliad leaf axils are abundant. I investigated individual spacing and activity patterns. Among the nine bromeliad species cultivated in the garden, the frogs used Vriesia neoglutinosa and plants structurally similar to it more than expected according to their availability. Phyllodytes luteolus uses V. neoglutinosa in its natural habitat. For one bromeliad species (Sp 1), frogs used proportionally more those plants that were higher (57.7 +/- 8.4 cm above ground), had lower pH (4.94 +/- 0.88), and deeper phytotelmata (5.38 +/- 2.09 cm). Plant height, phytotelmata depth, and PH had no influence on frogs' choices in the other bromeliad species tested. Males were active all night, and calling activity was highest immediately after sunset. Some males called during the day. Males did not exibit aggressive behavior towards other males, including those intruding onto their calling sites. The high availability of phytotelmata for calling and retreat in this modified environment may have influenced the low levels of aggression observed for this population of P. luteolus.331172

    New species of Proceratophrys (Anura : Leptodactylidae) from southeastern Brazil

    No full text
    Proceratophrys cururu, a species superficially similar to P. cristiceps and P. goyana, is described as new from the Serra do Cipo, Minas Gerais, southeastern Brazil. The new species differs from both P. cristiceps and P. goyana by its more contrasting dorsal color pattern, larger and more heterogeneous dorsal tubercles, dorsal tubercular rows interrupted in the sacral region, and two to three large tubercles in the suprascapular region.115916
    corecore