Mostrando entradas con la etiqueta Amphibia. Mostrar todas las entradas
Mostrando entradas con la etiqueta Amphibia. Mostrar todas las entradas

06 agosto 2010

Nuevos Animales Ecuador: Nuevo Sapito Andino (Anura: Bufonidae)

Una nueva especie de sapito andino del género Osornophryne fue descubierto en la Cordillera Oriental de Ecuador y acaba de ser descrita para la ciencia. Esta colorida nueva especie ha sido nombrada Osornophryne cofanorum en honor a la étnia indígena Cofán, importante cultura nativa Ecuatoriana asentada en la región Amazónica de la frontera entre Ecuador y Colombia, en cuyo territorio fue descubierto el nuevo sapito andino.

Osornophryne cofanorum, nueva especie de sapito andino encontrado en la provincia de Sucumbíos, Ecuador. Fotografía: J.J. Mueses-Cisneros.

Este sapito andino de los Cofanes O. cofanorum vive en las estribaciones orientales de los Andes norte de Ecuador, en la provincia de Sucumbíos, a una altitud entre 2.600 y 2.800 m. Es muy similar a otra especie llamada Osornophryne guacamayo, pero las coloridas pústulas amarillas en la cabeza y dorso de la nueva especie los diferencian.

Osornophryne cofanorum es conocido hasta el momento sólo de la localidad de Alto La Bonita, donde habita en arbustos y bromelias del bosque nublado.

La descripción de esta nueva especie fue realizada en colaboración entre científicos ecuatorianos y colombianos asociados al Museo Ecuatoriano de Ciencias Naturales y la Universidad Católica del Ecuador. El artículo fue publicado en la revista científica Papéis Avulsos de Zoologia.

CITA: Mueses-Cisneros JJ, Yánez-Muñoz MH, Guayasamin JM (2010) Una nueva especie de sapo del género Osornophryne (Anura: Bufonidae) de las estribaciones amazónicas de los Andes de Ecuador. Papéis Avulsos de Zoologia (São Paulo) 50(17): 269-279. doi: 10.1590/S0031-10492010001700001.

04 agosto 2010

Eleutherodactylus portoricensis

365especies.com Biodiversidad con nombre propio (o científico)

Eleutherodactylus portoricensis



Eleutherodactylus portoricensis es el nombre científico del coquí de montaña, una pequeña rana de Puerto Rico que habita bosques de montaña por encima de 180 metros de altitud. Es de color uniforme, usualmente amarillo o crema. Durante el día la especie se oculta bajo la hojarasca del bosque, y al llegar la noche sale de sus refugios diurnos y asciende sobre la vegetación.

El nombre del género, Eleutherodactylus, significa algo así como 'dedos libres', lo que hace referencia a que en las especies de este género no hay membranas interdigitales. En cuanto al nombre común, 'coquí', se trata de una onomatopeya del sonido que emiten los machos en su llamada.

18 julio 2010

Phyllobates vittatus

365especies.com Biodiversidad con nombre propio (o científico)

Phyllobates vittatus: "

Phyllobates vittatus es el nombre científico de la rana de punta de flecha rayada, un pequeño anfibio de Costa Rica. Tiene el dorso y la cabeza de color negro, y una llamativa banda dorsolateral dorada o naranja que la recorre desde la base del muslo hasta la boca. Vive en el suelo de los bosques húmedos, y se alimenta de hormigas y otros pequeños insectos.
Es uno de los anfibios conocidos más venenosos, ya que a través de la piel secreta una sustancia llamada batracotoxina, que ataca a los músculos y al corazón produciendo arritmias y fallo cardíaco.

28 marzo 2010

Dendrobates azureus: 365especies.com

365especies.com Biodiversidad con nombre propio (o científico)

Dendrobates azureus: "

Dendrobates azureus es el nombre científico de la rana flecha azul. Este anfibio vive en el Sur de Surinam, en los bosques que rodean a la Sabana de Sipaliwini. Pesa sólo tres gramos y luce un brillante color azulado que avisa a sus posibles depredadores de que es muy, muy venenosa. Su piel está cubierta de miles de glándulas que secretan un veneno con el que puede paralizar a sus más temibles enemigos. El patrón de manchas que muestra en el dorso es único para cada rana, y funciona como una especie de 'huella dactilar' que permite su identificación. Le gustan los ambientes húmedos, por lo que pasa la mayoría del tiempo cerca de arroyos y en rocas cubiertas de musgo. En ocasiones asciende a los árboles, trepando hasta alturas de 5 metros. De hecho su nombre, Dendrobates, procede del griego y significa ‘que camina por los árboles’. En cada pata, esta rana tienen cuatro dedos con una especie de ventosa en la punta que le ayuda a mantener el equilibrio mientras camina entre las resbaladizas piedras y a escalar. Su dieta consiste principalmente en hormigas, escarabajos, moscas, ácaros, arañas, termitas, gusanos y orugas.
Las ranas flecha azul son bastante territoriales y en ocasiones se enfrascan en violentas luchas para defender su “hogar” o para conseguir pareja.

"

13 diciembre 2009

Rana de Cristal en Peligro Crítico de Extinción por pérdida de hábitat

La rana de cristal Cochranella mache es un anfibio endémico del noroccidente de Ecuador, solo habita en las montañas de Mache en la Cordillera de Costa. En un reciente artículo (Cisneros-Heredia et al. 2010), publicado en la revista Oryx, The International Journal of Conservation, se revisa el rango geográfico de la especie y su actual estado de conservación. Este artículo recomienda la clasificación de esta especie de rana de cristal bajo la categoría IUCN de "Peligro Crítico" debido a su precario estado de conservación, al parecer causado por cambios climáticos locales producidos por la extensiva destrucción de los bosques.


27 julio 2009

New Taxonomy Centrolenidae

Phylogenetic systematics of Glassfrogs (Amphibia: Centrolenidae) and their sister taxon Allophryne ruthveni

Abstract.-- Based on a molecular phylogeny, a new phylogenetic taxonomy that is compatible with both the International Code of Zoological Nomenclature (ICZN) and the PhyloCode is proposed for Glassfrogs and their sister taxon, Allophryne ruthveni. The arrangement presented herein emphasizes the recognition of clades having (i) significant statistical support and congruence among phylogenetic estimation methods (i.e., parsimony, maximum likelihood, and Bayesian inference criteria), (ii) congruence among genetic markers, and (iii) morphological and/or behavioral distinctiveness. Also, when previously recognized groups are recovered as monophyletic or nearly monophyletic, we propose taxa that minimize the number of name changes required to make these groups monophyletic, preserving the names and contents of previous classifications (i.e., nomenclatural stability). The evolutionary proximity of Centrolenidae and Allophrynidae is recognized by combining these families into an unraked taxon, Allocentroleniae—a proposal that maintains the traditional names and species contents of Centrolenidae and Allophrynidae. We arrange centrolenid diversity in two subfamilies: Centroleninae and Hyalinobatrachinae. Within Centroleninae, the diagnosis and species content of the genera Centrolene, Cochranella, and Nymphargus are modified; Teratohyla is resurrected and modified, and Chimerella, Espadarana, Rulyrana, Sachatamia, and Vitreorana are proposed as new genera. The other subfamily, Hyalinobatrachinae, contains the new genus Celsiella and a modified Hyalinobatrachium that fully corresponds to the former fleischmanni Group. Additionally, the genus Ikakogi is described. Ikakogi could not be assigned with confidence to either subfamily and it is placed as incertae sedis in Centrolenidae. The data at hand suggest that Ikakogi tayrona is a lineage as old as the subfamilies Hyalinobatrachinae and Centroleninae. The revised taxonomy differs markedly from previous arrangements, which were based on phenetics and few morphological characters. Most of the genera defined herein are confined to distinct biogeographic regions, highlighting the importance of geography in the speciation of Glassfrogs. The principal limitation of this proposal is that it is based on an incomplete sampling of taxa (54% of the recognized Glassfrogs). Although diagnoses are based on phenotypic traits, there are several cases (16% of all species) in which the allocation of species is ambiguous because of morphological homoplasy and the lack of molecular data. Finally, in an attempt to facilitate species identification, comparison, and generic placement, we provide photographs for most (~ 96%) of the recognized centrolenid species.

Cita / Citation: Guayasamin, J. M., S. Castroviejo-Fisher, L. Trueb, J. Ayarzagüena, M. Rada, y C. Vilà. (2009) Phylogenetic systematics of glassfrogs (Amphibia: Centrolenidae) and their sister taxon Allophryne ruthveni. Zootaxa 2100:1-97.

Mas información: http://www.mapress.com/zootaxa/2009/f/zt02100p097.pdf
Phylogenetic relationships of glassfrogs (Centrolenidae) based on mitochondrial and nuclear genes

Abstract.-- Glassfrogs (family Centrolenidae) represent an exceptionally diverse group among Neotropical anurans, but their evolutionary relationships never have been assessed from a molecular perspective. Mitochondrial and nuclear markers were used to develop a novel hypothesis of centrolenid phylogeny. Ingroup sampling included 100 terminals, with 78 (53%) of the named species in the family, representing most of the phenotypic diversity described for the group. Thirty-five species representing taxa traditionally associated with glassfrogs were used as outgroups. Gene sampling consisted of complete or partial sequences of three mitochondrial (12S, 16S, ND1) and three nuclear markers (c-myc exon 2, RAG1, POMC) for a total of approximately 4362bp. Phylogenies were estimated using maximum parsimony, maximum likelihood, and Bayesian analyses for individual genes and combined datasets. The separate analysis of mitochondrial and nuclear datasets allowed us to clarify the relationships within glassfrogs; also, we corroborate the sister-group relationship between Allophryne ruthveni and glassfrogs. The new phylogeny differs significantly from all previous morphology-based hypotheses of relationships, and shows that hypotheses based on few traits are likely to misrepresent evolutionary history. Traits previously hypothesized as unambiguous synapomorphies are shown to be homoplastic, and all genera in the current taxonomy (Centrolene, Cochranella, Hyalinobatrachium, Nymphargus) are found to be poly- or paraphyletic. The new topology implies a South American origin of glassfrogs and reveals allopatric speciation as the most important speciation mechanism. The phylogeny profoundly affects the traditional interpretations of glassfrog taxonomy, character evolution, and biogeography-topics that now require more extensive evaluation in future studies..

Cita / Citation: Guayasamin, J. M., S. Castroviejo-Fisher, J. Ayarzagüena, L. Trueb y C. Vilà. (2008) Phylogenetic relationships of glassfrogs (Centrolenidae) based on mitochondrial and nuclear genes. Molecular Phylogenetics and Evolution 48:574-595.

Mas información: http://www.puce.edu.ec/zoologia/vertebrados/personal/colaboradores/jmguayasamin/index.html

Cochranella mcdiarmidi sp. nov.

A New Species of Glassfrog (Anura: Centrolenidae) from the Foothill Andean Forests of Ecuador and Peru

Abstract.-- We describe a new species of glassfrog assigned to the genus Cochranella (Amphibia: Anura: Athesphatanura: Centrolenidae) from the Foothill Evergreen forests on the southeastern Andean slopes of Ecuador and northeastern Andean slopes of Peru. The new species is characterized by its moderate-sized body (25.4–26.9 mm in adult males), medium-sized eyes (eye diameter/third disc width = 1.4–1.9), distinctive coloration in life (olive green with light spots) and in preservative (grayish lavender with pale spots), dorsal skin covered with flat warts and low tubercles, parietal peritoneum mostly white (covered by iridophores), thick ulnar folds, and extensive hand and foot webbing. In addition, we provide the first record of Nymphargus posadae from Peru, found in sympatry with the new species at the Cordillera del Cóndor..

Cita / Citation: Cisneros-Heredia, D.F., P. J. Venegas, M. Rada & R. Schulte. 2008. A new species of Glassfrog (Anura, Centrolenidae) from the Foothill Andean forests of Ecuador and Peru. Herpetologica 64(3): 342-353..

Mas información: http://www.cisneros-heredia.org/public

23 julio 2008

Centrolene condor sp. nov.

A new species of glassfrog from the elfin forests of the Cordillera del Cóndor, southeastern Ecuador (Anura: Centrolenidae)

Abstract.-- We describe a new species of glassfrog of the genus Centrolene (Amphibia: Anura: Athesphatanura: Centrolenidae) that inhabits the elfin forests of the Cordillera del Cóndor, an isolated mountain chain separated from the Cordillera Oriental of the Andes by the valley of the River Zamora. This new species is characterized by having vomerine teeth; a subacuminated snout in dorsal view and strongly sloping in profile; a tympanic annulus rather indistinct; shagreened dorsal skin with low warts and abundant spicules; a subcloacal area granular with several enameled warts; humeral spines in adult males; enameled ulnar folds; enameled metatarsal folds; a row of distinct enameled tubercles along the outer tarsal edges; and a green dorsum in life with abundant light and dark flecks. This taxon is the most distinct of a phenetic-set of species that includes Centrolene altitudinale, C. buckleyi, C. heloderma, C. hesperium, C. lemniscatum, and C. venezuelense.

Cita / Citation: Cisneros-Heredia, D.F. & Morales-Mite, M.A. (2008) A new species of glassfrog from the elfin forests of the Cordillera del Cóndor, southeastern Ecuador (Anura: Centrolenidae). Herpetozoa 21 (1/2): 49-56.

Mas información: http://www.cisneros-heredia.org/public

Osornophryne puruanta

A new species of Osornophryne (Anura: Bufonidae) from the Andean highlands of northern Ecuador

Abstract.-- Gleusenkamp & Guayasamin (2008) described a new species of the genus Osornophryne from the vicinities of Laguna de Puruanta and Laguna de San Marcos in the Andean highlands of northeastern Ecuador. The new species is the largest known member of the genus (female snout-vent length = 40.5–47.1 mm; males unknown) and is remarkable for having a smooth dorsal skin lacking conical tubercles and interspersed with numerous glandular pustules. The new species has a clutch size of about 30 eggs and is likely nocturnal.

Cita / Citation: Gluesenkamp, A. G. & Guayasamin, J.M. (2008) A new species of Osornophryne (Anura: Bufonidae) from the Andean highlands of northern Ecuador. Zootaxa 1828: 18-28.

Correo electrónico del autor: Andrew Gluesenkamp andy@gluesenkamp.com.

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.

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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.

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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.

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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.

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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 .

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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

06 noviembre 2007

Bufo anderssoni synonym of Rhaebo guttatus

The taxonomic status of Rhaebo anderssoni (Melin, 1941) (Anura: Bufonidae)

Abstract.-- Bufo anderssoni Melin, 1941 is synonymised with Rhaebo guttatus (Schneider, 1799) based on direct comparison of the holotypes of both and fresh material. All characters of the former fall within the intraspecific variation of R. guttatus. The few characters used in the original description to distinguish anderssoni from guttatus (narrower interorbital space, smaller tympanum and smaller size) are not considered important interspecific differences, but rather dependent on ontogenetic development.

Cita / Citation: Barrio-Amorós, C. L. & Castroviejo-Fisher, S. (2007) The taxonomic status of Rhaebo anderssoni (Melin, 1941) (Anura: Bufonidae). Salamandra 43(4): 250-253.

Correos electrónicos de los autores: Cesar L. Barrio-Amoros cesarlba@yahoo.com, Santiago Castroviejo-Fisher santiago.castroviejo@ebc.uu.se.

Stress in Invasive Cane Toads

Invasion, stress, and spinal arthritis in cane toads

Abstract.-- The impact of invasive species on biodiversity has attracted considerable study, but impacts of the invasion process on the invaders themselves remain less clear. Invading species encounter conditions different from those in their ancestral habitats and are subject to intense selection for rapid dispersal. The end result may be significant stress on individual organisms, with consequent health problems. Our studies on invasive cane toads in Australia reveal severe spinal arthritis in c. 10% of large adult toads, associated with the same factors (large body size, frequent movement, and relatively long legs) that have enabled toads to invade so rapidly across the Australian tropics.

Cita / Citation: Brown, G. P., Shilton, C., Phillips, B. L. & Shine, R. (2007) Invasion, stress, and spinal arthritis in cane toads. PNAS 104(45). 10.1073/pnas.0705057104

Autor a quien correspondencia debe ser dirigida: Richard Shine rics@bio.usyd.edu.au

Enlace al Abstract (acceso gratis a la publicación completa en paises de Latinoamerica):
http://www.pnas.org/cgi/content/abstract/104/45/17698

04 noviembre 2007

Underestimation of Species Richness in Neotropical Frogs

Underestimation of Species Richness in Neotropical Frogs Revealed by mtDNA Analyses

Abstract.-- Background. Amphibians are rapidly vanishing. At the same time, it is most likely that the number of amphibian species is highly underestimated. Recent DNA barcoding work has attempted to define a threshold between intra- and inter-specific genetic distances to help identify candidate species. In groups with high extinction rates and poorly known species boundaries, like amphibians, such tools may provide a way to rapidly evaluate species richness. Methodology. Here we analyse published and new 16S rDNA sequences from 60 frog species of Amazonia-Guianas to obtain a minimum estimate of the number of undescribed species in this region. We combined isolation by distance, phylogenetic analyses, and comparison of molecular distances to evaluate threshold values for the identification of candidate species among these frogs. Principal Findings. In most cases, geographically distant populations belong to genetically highly distinct lineages that could be considered as candidate new species. This was not universal among the taxa studied and thus widespread species of Neotropical frogs really do exist, contrary to previous assumptions. Moreover, the many instances of paraphyly and the wide overlap between distributions of inter- and intra-specific distances reinforce the hypothesis that many cryptic species remain to be described. In our data set, pairwise genetic distances below 0.02 are strongly correlated with geographical distances. This correlation remains statistically significant until genetic distance is 0.05, with no such relation thereafter. This suggests that for higher distances allopatric and sympatric cryptic species prevail. Based on our analyses, we propose a more inclusive pairwise genetic distance of 0.03 between taxa to target lineages that could correspond to candidate species. Conclusions. Using this approach, we identify 129 candidate species, two-fold greater than the 60 species included in the current study. This leads to estimates of around 170 to 460 frog taxa unrecognized in Amazonia-Guianas. Significance. As a consequence the global amphibian decline detected especially in the Neotropics may be worse than realised.

Cita / Citation: Fouquet, A., Gilles, A., Vences, M., Marty, C., Blanc, M. & Gemmellet, N. J. (2007) Underestimation of Species Richness in Neotropical Frogs Revealed by mtDNA Analyses. PLoS ONE 2(10): e1109. doi:10.1371/journal.pone.0001109

Acceso libre al artículo y al pdf / Open access to the article and its pdf: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0001109

<<PLoS ONE (eISSN-1932-6203) is an international, peer-reviewed, open-access, online publication. PLoS ONE welcomes reports on primary research from any scientific discipline. PLoS ONE is published by the Public Library of Science (PLoS), a nonprofit organization. PLoS ONE's start-up phase is supported by a grant from the Open Society Institute.>>

09 octubre 2007

Cochranella erminea sp. nov.

Cochranella erminea, a new species of Centrolenidae (Amphibia: Anura: Athesphatanura) from Amazonian Peru)

Abstract.--We describe a new species of Centrolenidae, Cochranella erminea n. sp., from the Amazonian lowlands of the department of Junín, Peru. This new species is diagnosed from other centrolenids by having vomerine teeth, bones green in life, parietal peritoneum and pericardium white, all other visceral peritonea clear, dorsum in life viridian to olive green with abundant enameled (bright white) flecks/spots on flat warts, and scattered larger dark blue spots on warts, extensive webbing between outer fingers, snout in profile slightly sloping anteroventraly, and rounded in dorsal view, iris in life between light grey and slate gray with fine darker gray reticulations. We also present new information on the distribution of C. truebae and C. ametarsia in Peru..

Cita / Citation: Torres-Gastello, C.P., J. Suarez-Segovia, J. & D.F. Cisneros-Heredia. 2007. Cochranella erminea, a new species of Centrolenidae (Amphibia: Anura: Athesphatanura) from Amazonian Peru. Journal of the National Museum (Prague), Natural History Series 176 (1): 1-12.

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31 agosto 2007

Nymphargus new genus

Revision of the characters of Centrolenidae (Amphibia: Anura: Athesphatanura), with comments on its taxonomy and the description of new taxa of glassfrogs

Abstract.--Anurans of the family Centrolenidae are a diverse clade of arboreal frogs distributed across tropical America. Knowledge of their taxonomy, systematics, ecology, behavior, morphology, and other evolutionary aspects of their biology is deficient. Relationships among centrolenid species remain largely unresolved, with no satisfactory phylogenetic hypothesis, and none of the current genera has compelling evidence of monophyly. Further, understanding the phylogeny of glassfrogs is constrained by species-level taxonomic problems, including incorrect description of characters, incomplete analyses of intraspecific variation, and lack of appreciation of species diversity. Herein, we define and analyze the 23 characters that are useful, in combination, in diagnosing centrolenid species, and thereby provide a reference for the use of future workers. We propose revised classifications for the parietal and visceral peritoneal pigmentation, liver form and coloration of its associated hepatic peritoneum, nuptial excrescences, and hand ornamentation. We comment on the generic and species-level taxonomy of Centrolenidae, proposing the recognition of a new genus and describing a new species from Ecuador. We treat Hyla ocellifera Boulenger as a synonym of Centrolene prosoblepon (Boettger), Hyalinobatrachium cardiacalyptum McCranie & Wilson as a synonym of Hyalinobatrachium chirripoi (Taylor), and Hyalinobatrachium crybetes McCranie and Wilson as a synonym of Hyalinobatrachium colymbiphyllum (Taylor). We also present an annotated list of the species of glassfrogs from the Republic of Ecuador with some distributional remarks.

Resumen.--Los anuros de la familia Centrolenidae forman un clado diverso de ranas arbóreas distribuidas a lo largo de América tropical. El conocimiento sobre su taxonomía, sistemática, ecología, comportamiento, morfología y otros aspectos biológicos y evolutivos es deficiente. Las relaciones entre las especies de centrolénidos permanecen ampliamente sin resolver, sin hipótesis filogenéticas satisfactorias y todos los géneros actuales tienen evidencia clara de su no-monofília. Más aún, el entendimiento de la filogenia de las ranas de cristal está limitado por problemas taxonómicos al nivel de especies, incluyendo la descripción incorrecta de caracteres, análisis incompletos de la variación intraespecífica y la falta de apreciación de la diversidad de especies. En este trabajo, nosotro definimos y analizamos los 23 caracteres que son útiles, en combinación, para diagnosticar todas las especies de centrolénidos, proveyendo una referencia para el uso de futuros investigadores. Proponemos clasificaciones revisadas para la pigmentación de los peritoneos parietal y visceral, la forma del hígado y la coloración del peritoneo hepático asociado, las excrescencias nupciales y las ornamentaciones manuales. Comentamos sobre la taxonomía a nivel genérico y específico de Centrolenidae, proponiendo el reconocimiento de un nuevo género y la descripción de una nueva especie de Ecuador. Colocamos a Hyla ocellifera Boulenger como un sinónimo de Centrolene prosoblepon (Boettger); a Hyalinobatrachium cardiacalyptum McCranie & Wilson como sinónimo de Hyalinobatrachium chirripoi (Taylor); y a Hyalinobatrachium crybetes McCranie and Wilson como sinónimo de Hyalinobatrachium colymbiphyllum (Taylor). Presentamos una lista anotada de las especies de ranas de cristal de la República del Ecuador con algunos comentarios sobre su distribución.

Cita / Citation: Cisneros-Heredia, D. F. & R. W McDiarmid. 2007. Revision of the characters of Centrolenidae (Amphibia: Anura: Athesphatanura), with comments on its taxonomy and the description of new taxa of glassfrogs. Zootaxa 1572: 1-82.

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27 agosto 2007

Centrolene durrellorum sp. nov.

A new species of glassfrog of the genus Centrolene from the foothills of Cordillera Oriental of Ecuador (Anura: Centrolenidae)

Abstract.--A new species of frog of the family Centrolenidae is described from Ecuador, Centrolene durrellorum sp. nov. This new taxon is the first species of the genus Centrolene known to inhabit the central and southern foothills of the Cordillera Oriental of Ecuador. The new species is diagnosed from other centrolenid taxa by its moderate body size (25.7–26.1 mm adult males), uniform coloration (green in life, pale lavender in preservative), rounded snout in dorsal and lateral views, presence of medium-sized straight humeral spines with a moderate spiny point in adult males and absence of guanophores on the visceral peritonea.

Cita / Citation: Cisneros-Heredia, D. F. 2007. A new species of glassfrog of the genus Centrolene
from the foothills of Cordillera Oriental of Ecuador. Herpetozoa 20 (1/2)
: 27-34.

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23 agosto 2007

Cochranella buenaventura sp. nov.

A NEW SPECIES OF GLASSFROG (CENTROLENIDAE) FROM THE SOUTHERN ANDEAN FOOTHILLS ON THE WEST ECUADORIAN REGION

Abstract.--Cochranella buenaventura sp. nov. is described from the southern foothills of the Cordillera Occidental, Andes of Ecuador. The new species inhabits the Seasonal Foothill Evergreen forests of the province of El Oro, in the West Ecuadorian biogeographic region. This species is distinguished from other species of glassfrogs by having a truncate snout in dorsal and lateral views, reduced webbing between fingers, absence of guanophores on the digestive visceral peritonea, but present on the renal capsule, absence of humeral spine, green dorsum in life with scattered pale yellow spots, bright yellow hands and feet discs, and moderate body size (20.9-22.4 mm snout-vent length in adult males).

Cita / Citation: Cisneros-Heredia, D. F. & M. H. Yánez-Muñoz. 2007. A NEW SPECIES OF GLASSFROG (CENTROLENIDAE) FROM THE SOUTHERN ANDEAN FOOTHILLS ON THE WEST ECUADORIAN REGION. South American Journal of Herpetology 2(1): 1-10.

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07 agosto 2007

Hyalinobatrachium ruedai

NUEVA PUBLICACION / NEW PUBLICATION:

Primer registro de Hyalinobatrachium ruedai en Ecuador con notas sobre otras especies congenericas

Resumen.--Reportamos el primer registro de Hyalinobatrachium ruedai para Ecuador, extendiendo su distribución desde Colombia hasta los flancos centrales de la Cordillera Oriental de Ecuador. El análisis del material adicional y de la serie tipo de H. ruedai nos permite discutir su variación morfológica y de coloración. Algunas características previamente conocidas solo para taxones del Macizo Guayanés (ej. iris bicolor) son reportadas en H. ruedai. Se recomienda no subdividir al grupo H. fleischmanni en subgrupos. Comentamos el estado taxonómico de algunas especies de la región Pacífica de Ecuador, caracterizamos a H. petersi y reconocemos que actualmente bajo los nombres Hyalinobatrachium fleischmanni y H. valerioi hay al menos tres especies aún no descritas.

Abstract.--We report the first record of Hyalinobatrachium ruedai for Ecuador, extending its distribution range from Colombia to the central slopes of the Cordillera Oriental of Ecuador. Analysis of additional material and the type series of H. ruedai let us to comment on its morphological and coloration variation. Some characters previously known just from taxa of the Guiana Shield (eg. bicolored iris) are reported from H. ruedai. We suggest to maintain undivided the H. fleischmanni group, without recognition of subgroups. We comment on the taxonomic status of some species from the Pacific region of Ecuador, characterizing H. petersi, and recognizing that currently under the names Hyalinobatrachium fleischmanni y H. valerioi there are at least three new species.


Cita / Citation: Cisneros-Heredia, D. F. & R. W. McDiarmid. 2007. Primer registro de Hyalinobatrachium ruedai en Ecuador con notas sobre otras especies congenericas. Herpetotropicos 3 (1): 21-28.

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29 mayo 2007

Cochranella amelie sp. nov.

NUEVA PUBLICACION / NEW PUBLICATION:

An enigmatic new species of Glassfrog (Amphibia: Anura: Centrolenidae) from the Amazonian Andean slopes of Ecuador

Abstract.--We describe a new species of frog of the family Centrolenidae, Cochranella amelie n. sp., from the central Amazonian Andean slopes, collected at the Oglan River, Province of Pastaza, Ecuador. This new species shows a very unusual combination of characters (lavender dorsum in preservative, absence of a humeral spine in adult males, transparent parietal peritoneum, white visceral peritonea, and bulbous liver). The relationships of this new species of Glassfrog are uncertain, and its assignment to Cochranella is preliminary.

Resumen.--Describimos una nueva especie de rana de la familia Centrolenidae, Cochranella amelie n. sp., de los flancos Andinos Amazónicos centrales, colectada en el Río Oglán, Provincia de Pastaza, Ecuador. Esta nueva especie presenta una muy inusual combinación de caracteres (dorso de color lavanda en preservante, ausencia de espina humeral en machos adultos, peritoneo parietal transparente, peritoneos viscerales blancos, e hígado bulboso). Las relaciones de esta nueva especie de Rana de Cristal son inciertas y su asignación a Cochranella es preliminar.

Cita / Citation: Cisneros-Heredia, D. F. & P. Meza-Ramos. 2007. An enigmatic new species of Glassfrog (Amphibia: Anura: Centrolenidae) from the Amazonian Andean slopes of Ecuador. Zootaxa 1485: 33-41.

Mas información: http://www.cisneros-heredia.org/public