25 abril 2008

COPEIA articles

Secondary Homonymy of Bufo proboscideus Spix, 1824, with Phryniscus proboscideus Boulenger, 1882

Abstract.-- Chaparro et al. (2007) placed Rhamphophryne Trueb, 1971 into the synonymy of Rhinella Fitzinger, 1826. This resulted in Bufo (Oxyrhynchus) proboscideus Spix, 1824 (formerly Rhinella proboscidea) and Phryniscus proboscideus Boulenger, 1882 (formerly Rhamphophryne proboscidea) rendered as secondary homonyms. The new name Rhinella boulengeri is provided as a replacement for the junior name, Phryniscus proboscideus.

Cita / Citation: Chaparro, J.C., Pramuk, J.B., Gluesenkamp, A.G., and Frost D.R. (2007) Secondary Homonymy of Bufo proboscideus Spix, 1824, with Phryniscus proboscideus Boulenger, 1882. COPEIA 2007(4): 1029.

Correo electrónico del autor: Juan Carlos Chaparro jchaparroauza@yahoo.com.


A Name for the Species of Allobates (Anura: Dendrobatoidea: Aromobatidae) from the Magdalena Valley of Colombia

Abstract.-- We describe a new species of Allobates from the Magdalena Valley in Colombia. The new species and its sister species, A. talamancae, are the only two species of Allobates known to occur west of the Andes. The new species differs from A. talamancae in being smaller, possessing a diffuse pale oblique lateral stripe, and exhibiting strong swelling of finger III in adult males. Tadpoles also differ in the relative size of anterior and posterior labial papillae; in the new species anterior papillae are conspicuously larger than posterior papillae, whereas in A. talamancae they are subequal in size. Allobates talamancae and the new species are allopatric. Among the cis-Andean species of Allobates, the new species most resembles A. melanolaemus, which also possesses a diffuse pale oblique lateral stripe and a solid black throat in adult males, but from which it differs in being smaller and adult males having finger III strongly swollen and solid black pigmentation covering the chest and most of the belly..

Cita / Citation: Grant, T., Acosta, A., and Rada, M. (2007) A Name for the Species of Allobates (Anura: Dendrobatoidea: Aromobatidae) from the Magdalena Valley of Colombia. COPEIA 2007(4): 844–854.

Correos electrónicos de los autores: Taran Grant taran.grant@pucrs.br, Andres Acosta andres.acosta@javeriana.edu.co, Marco Rada radamarco@hotmail.com.


Global Rates of Habitat Loss and Implications for Amphibian Conservation

Abstract.-- A large number of factors are known to affect amphibian population viability, but most authors agree that the principal causes of amphibian declines are habitat loss, alteration, and fragmentation. We provide a global assessment of land use dynamics in the context of amphibian distributions. We accomplished this by compiling global maps of amphibian species richness and recent rates of change in land cover, land use, and human population growth. The amphibian map was developed using a combination of published literature and digital databases. We used an ecoregion framework to help interpret species distributions across environmental, rather than political, boundaries. We mapped rates of land cover and use change with statistics from the World Resources Institute, refined with a global digital dataset on land cover derived from satellite data. Temporal maps of human population were developed from the World Resources Institute database and other published sources. Our resultant map of amphibian species richness illustrates that amphibians are distributed in an uneven pattern around the globe, preferring terrestrial and freshwater habitats in ecoregions that are warm and moist. Spatiotemporal patterns of human population show that, prior to the 20th century, population growth and spread was slower, most extensive in the temperate ecoregions, and largely exclusive of major regions of high amphibian richness. Since the beginning of the 20th century, human population growth has been exponential and has occurred largely in the subtropical and tropical ecoregions favored by amphibians. Population growth has been accompanied by broad-scale changes in land cover and land use, typically in support of agriculture. We merged information on land cover, land use, and human population growth to generate a composite map showing the rates at which humans have been changing the world. When compared with the map of amphibian species richness, we found that many of the regions of the earth supporting the richest assemblages of amphibians are currently undergoing the highest rates of landscape modification.

Cita / Citation: Gallant, A.L., Klaver, R.W., Casper, G.S., and Lannoo, M.J. (2007) Global Rates of Habitat Loss and Implications for Amphibian Conservation. COPEIA 2007(4): 967–979.

Correo electrónico del autor: Michael J. Lannoo mlannoo@iupui.edu.


Experimental Evidence for Aposematism in the Dendrobatid Poison Frog Oophaga pumilio

Abstract.-- Brightly colored poison frogs of the family Dendrobatidae contain an alkaloid-based chemical defense against predation. The bright coloration of these frogs is generally considered an aposematic signal to potential predators; however, relatively few studies have specifically tested this hypothesis. Herein we report the results of a field-based experiment designed to test the hypothesis of aposematism in the dendrobatid frog, Oophaga (=Dendrobates) pumilio from the La Selva Biological Station, Costa Rica. We used plasticine frog models to evaluate natural predation rates as a function of color. Predation rates on brown models were almost twice that of red models, suggesting that predators avoid brightly colored frog models. Birds accounted for the majority of attacks on the models. The results of this study provide experimental evidence in support of the hypothesis that bright coloration in dendrobatids functions as an aposematic signal to predators.

Cita / Citation: Saporito, R.A., Zuercher, R., Roberts, M., Gerow, K.G., and Donnelly., M.A. (2007) Experimental Evidence for Aposematism in the Dendrobatid Poison Frog Oophaga pumilio. COPEIA 2007(4): 1006–1011.

Correo electrónico del autor: Ralph Saporito ralph.saporito@gmail.com.


Phylogeny and Ecology Determine Morphological Structure in a Snake Assemblage in the Central Brazilian Cerrado

Abstract.-- To investigate the role of ecological and historical factors in the organization of communities, we describe the ecomorphological structure of an assemblage of snakes (61 species in six families) in the Cerrado (a savanna-like grassland) of Distrito Federal, Brazil. These snakes vary in habits, with some being fossorial, cryptozoic, terrestrial, semi-aquatic, or arboreal. Periods of activity also vary. A multivariate analysis identified distinct morphological groups associated with patterns of resource use. We report higher niche diversification compared to snakes in the Caatinga (a semi-arid region in northeastern Brazil), with fossorial and cryptozoic species occupying morphological space that is not occupied in the Caatinga. Monte Carlo permutations from canonical phylogenetic ordination revealed a significant phylogenetic effect on morphology for Colubridae, Colubrinae, Viperidae, Elapidae, and Boidae indicating that morphological divergence occurred in the distant past. We conclude that phylogeny is the most important factor determining structure of this Neotropical assemblage. Nevertheless, our results also suggest a strong ecological component characterizes a peculiar snake fauna.

Cita / Citation: França, F.G.R., Mesquita, D.O., Nogueira, C.C., and Araújo, A.F.B. (2008) Phylogeny and Ecology Determine Morphological Structure in a Snake Assemblage in the Central Brazilian Cerrado. COPEIA 2008(1): 23–38.

Correo electrónico del autor: Frederico G.R França fgrf@unb.br .


Ecology of Anolis nitens brasiliensis in Cerrado Woodlands of Cantão

Abstract.-- We studied the ecology of Anolis nitens brasiliensis during late-dry and early-wet season 2005 in a Cerrado habitat in Tocantins state, Brazil. Most lizards were found on tree trunks or leaf litter in non-flooded igapó forest. Most were found in shade or filtered sun on both cloudy and sunny days. Body temperatures (Tbs) averaged 30.6°C and did not vary among microhabitats. Microhabitats exposed to direct sun consistently reached extremely high temperatures whereas microhabitats in shade or filtered sun provided temperatures throughout the day allowing lizard activity. Nineteen prey categories were found in lizard stomachs, but the diet was dominated by spiders, crickets/grasshoppers, ants, and beetles. Although lizards that ate large prey ate fewer prey, no correlation existed between size or number of prey and lizard body size (SVL). Males were larger in SVL and mass than females, and males had relatively longer hind limbs than females. Females were variable but larger in body width. In general, the ecology of Anolis n. brasiliensis is similar to that of its Amazonian relatives, with the exception that it lives in a more thermally extreme environment and is active at slightly higher Tbs. Ecological traits of this lizard, particularly its reliance on relatively low Tb for activity, suggest that it might be particularly vulnerable to local extinction if its habitat is altered. The presence and apparent widespread distribution of A. n. brasiliensis in the Cerrado provides further evidence that the “vanishing refuge” theory cannot account for geographical patterns of distribution in the A. nitens complex.

Cita / Citation: Vitt, L.J., Shepard, D.B., Vieira, G.H.C., Caldwell, J.P., Colli, G.R., and Mesquita , D.O. (2008) Ecology of Anolis Nitens Brasiliensis in Cerrado Woodlands of Cantão. COPEIA 2008(1): 144–153.

Correo electrónico del autor: Laurie J. Vitt vitt@ou.edu