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1.
Zootaxa ; 5264(3): 341-354, 2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37518045

RESUMO

The lack of basic natural history and distributional data represents a challenge for the conservation of rare and endemic amphibian species. This is the case of "Centrolene" acanthidiocephalum, a poorly known glassfrog endemic to the Cordillera Oriental of the Colombian Andes. This species was formally described in the late 1980s and no records have been reported over the last quarter century. Therefore, little is known about its distributional boundaries, morphological variation, natural history, and evolutionary relationships. Here we report the finding of a population of "Centrolene" acanthidiocephalum from a locality around its historical range and provide additional information on its geographic distribution, clutch size, and adult morphology. We also present for the first time data on tadpole morphology, as well as a description of its advertisement call and a phylogenetic tree based on mitochondrial genetic data corroborating its generic position within Centrolene.


Assuntos
Anuros , Vocalização Animal , Animais , Filogenia , Larva/genética , Larva/anatomia & histologia
2.
Zookeys ; 1158: 27-48, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37215692

RESUMO

A new salamander species of the genus Bolitoglossa is here described from the cloud forests of the western slopes of the Cordillera Oriental of Colombia, in the Cundinamarca department. The most salient characters of this new species are its numerous maxillary and vomerine teeth, its moderate webbing on hands and feet, its short and robust tail, and its chromatic variation. Based on molecular analyses this new species is assigned to the adspersa species group and its status established as the sister species of B.adspersa, with which it was previously confused. Lastly, the distribution, natural history, and conservation status of the new species are discussed.


ResumenDescribimos una nueva especie de salamandra del género Bolitoglossa proveniente de los bosques nublados de la vertiente occidental de la Cordillera Oriental de Colombia, en el departamento de Cundinamarca. Los caracteres más sobresalientes de esta nueva especie son sus numerosos dientes maxilares y vomerinos, su palmeadura moderada en pies y manos, su cola corta pero robusta, y su variación cromática. Basados en análisis moleculares asignamos esta nueva especie al grupo de especies adspersa y establecemos su estatus como especie hermana de B.adspersa, con la cual era previamente confundida. Finalmente, discutimos algunos aspectos de su distribución, historia natural y su estado de conservación.

3.
Zootaxa ; 5068(2): 247-262, 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34810710

RESUMO

The Neotropical frog genus Cryptobatrachus includes six currently recognized species distributed throughout the northern Andes in Colombia and Venezuela. Cryptobatrachus conditus, C. pedroruizi, and C. remotus were described from the Colombian and Venezuelan slopes of the Serrana del Perij. Due to the great morphological similarity among these species, we re-assess their taxonomic status based on morphological and molecular data from types, topotypes, and specimens from localities referred to in the original descriptions of these species. Morphometric comparisons showed that all these species are virtually indistinguishable, although some subtle qualitative differences in morphological traits distinguish C. conditus from the other species. Phylogenetic analyses of DNA sequences found that C. remotus and C. pedroruizi are not reciprocally monophyletic and exhibit low genetic divergence ( 1 %). Therefore, C. remotus should be considered a junior synonym of C. pedroruizi. This work stresses the importance of comprehensive taxon sampling in poorly explored areas, especially between neighbouring countries.


Assuntos
Anuros , Deriva Genética , Animais , Anuros/genética , Filogenia
4.
Zootaxa ; 4877(2): zootaxa.4877.2.7, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33311193

RESUMO

We describe a new species of diurnal gecko, Gonatodes castanae sp. nov. from the foothills of the Serranía de San Lucas, municipality of Norosí, Department of Bolívar, Colombia. The new species differs from all species in the genus by the combination of the following characters: moderate size, subcaudal scale pattern type B (1'1'1''), typically two rows of lateral scales on the digits, and aspects of color pattern in males (dorsum, flanks, limbs and tail with white ocelli on a black background) and females (dorsum, flanks, limbs and tail with brown to black reticulations and withe spots on a greenish-yellow background). The validity of the new species is also supported by molecular analyses. This species inhabits relicts of riverine forests at about 150 m above sea level (a.s.l.). Gonatodes castanae increases the number of known species in this genus to 34 and the species registered for Colombia to eight.


Assuntos
Lagartos , Distribuição Animal , Estruturas Animais , Animais , Colômbia , Feminino , Florestas , Masculino
5.
Zootaxa ; 4608(1): zootaxa.4608.1.11, 2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-31717168

RESUMO

The Neotropical genus Allobates Zimmerman Zimmerman (1988) is a large monophyletic clade composed of 54 described species distributed between Central America and South America (Frost, 2019; Grant et al., 2017). Twelve species have been recorded in Colombia, mostly distributed in the eastern flank of the Eastern Cordillera and Amazonian Region, although some species reach the Magdalena Valley and the Central and Western Cordillera (Acosta-Galvis, 2017).


Assuntos
Anuros , Animais , América Central , Colômbia , América do Sul
6.
Zootaxa ; 4382(1): 121-146, 2018 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-29689940

RESUMO

A new species of Hyloscirtus, belonging to the H. bogotensis species Group, is described from the Venezuelan and Colombian slopes of the Sierra de Perijá. The new species can be readily distinguished from its congeners by the combination of the following characters: mental gland present, disc-shaped and small; ulnar, outer, and inner tarsal folds present; calcar tubercle absent; whitish stripes on external border of upper eyelids and supratympanic folds, longitudinally on the mid-dorsum, on supracloacal fold, outer ulnar folds, inner and outer tarsal folds, and also on dorsal internal surface of shanks. We estimate phylogenetic relationships based on mtDNA (spanning fragments of 12S rRNA, tRNA-Val and 16S rRNA), of all Hyloscirtus species available in Genbank, as well as the new species described herein, H. callipeza, H. jahni, and H. platydactylus, all of which have not been previously sequenced. Our molecular data support the hypothesis of the new species as sister species of H. callipeza and indicates that H. jahni does not belong to the H. bogotensis species Group, but rather is sister species of all other Hyloscirtus (sensu Faivovich et al. 2005). Based on this last result we propose a new species group for H. jahni and the synonymy of Colomascirtus in Hyloscirtus. We also provide the first description of the advertisement call of H. callipeza. With the new species described herein, the number of Hyloscirtus species increases to 37.


Assuntos
Anuros , Animais , Colômbia , Filogenia , RNA Ribossômico 16S
7.
Ecol Evol ; 6(7): 1901-13, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26929819

RESUMO

Although biodiversity gradients have been widely documented, the factors governing broad-scale patterns in species richness are still a source of intense debate and interest in ecology, evolution, and conservation biology. Here, we tested whether spatial hypotheses (species-area effect, topographic heterogeneity, mid-domain null model, and latitudinal effect) explain the pattern of diversity observed along the altitudinal gradient of Andean rain frogs of the genus Pristimantis. We compiled a gamma-diversity database of 378 species of Pristimantis from the tropical Andes, specifically from Colombia to Bolivia, using records collected above 500 m.a.s.l. Analyses were performed at three spatial levels: Tropical Andes as a whole, split in its two main domains (Northern and Central Andes), and split in its 11 main mountain ranges. Species richness, area, and topographic heterogeneity were calculated for each 500-m-width elevational band. Spatial hypotheses were tested using linear regression models. We examined the fit of the observed diversity to the mid-domain hypothesis using randomizations. The species richness of Pristimantis showed a hump-shaped pattern across most of the altitudinal gradients of the Tropical Andes. There was high variability in the relationship between area and species richness along the Tropical Andes. Correcting for area effects had little impact in the shape of the empirical pattern of biodiversity curves. Mid-domain models produced similar gradients in species richness relative to empirical gradients, but the fit varied among mountain ranges. The effect of topographic heterogeneity on species richness varied among mountain ranges. There was a significant negative relationship between latitude and species richness. Our findings suggest that spatial processes partially explain the richness patterns of Pristimantis frogs along the Tropical Andes. Explaining the current patterns of biodiversity in this hot spot may require further studies on other possible underlying mechanisms (e.g., historical, biotic, or climatic hypotheses) to elucidate the factors that limit the ranges of species along this elevational gradient.

8.
Environ Mol Mutagen ; 54(5): 362-73, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23625742

RESUMO

The aerial spraying of glyphosate formulations in Colombia to eradicate illegal crops has generated great concern about its possible impact on nontarget organisms, particularly amphibians. This study evaluated the toxic, cytotoxic, and genotoxic effects of a glyphosate formulation (Roundup®SL-Cosmoflux®411F) in the direct-developing frog Eleutherodactylus johnstonei by estimating the median lethal application rate (LC50 ), median hemolytic application rate (HD50 ), and extent of DNA damage using the in vitro and in vivo Comet assays. Toxicity results indicated that the application rate [37.4 µg acid equivalent (a.e.)/cm(2) ] equivalent to that used in aerial spraying (3.74 kg a.e./ha) is not lethal in male and female adult frogs, whereas neonates are highly sensitive. Glyphosate formulation at application rates above 5.4 µg a.e./cm(2) (in vivo) and concentrations above 95 µg a.e./mL (in vitro) showed clear evidence of cytotoxicity. In vivo and in vitro exposure of E. johnstonei erythrocytes to the glyphosate formulation induced DNA breaks in a dose-dependent manner with statistically significant values (P < 0.05) at all doses tested. DNA damage initially increased with the duration of exposure and then decreased, suggesting that DNA repair events were occurring during in vivo and in vitro exposures. These results are discussed from the perspective of possible ecotoxicological risks to anuran species from exposure to glyphosate formulation.


Assuntos
Anuros/fisiologia , Glicina/análogos & derivados , Herbicidas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Anuros/crescimento & desenvolvimento , Células Cultivadas , DNA/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Feminino , Glicina/toxicidade , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Dose Letal Mediana , Masculino , Testes de Mutagenicidade , Fatores de Tempo , Glifosato
9.
Anat Rec (Hoboken) ; 296(7): 1019-30, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23625763

RESUMO

Over the last century, the morphogenesis of the vertebral column has been considered as a highly conserved process among anurans. This statement is based on the study of few metamorphic taxa, ignoring the role of developmental mechanisms underlying the evolution of specialized life-histories. Direct development in anurans has been regarded as evolutionarily derived and involves developmental recapitulation and repatterning at different levels in all amphibian taxa studied so far. Herein, we analyze the vertebral column morphogenesis of the direct-developing frog Eleutherodactylus johnstonei, describing the sequence of chondrification and ossification, based on cleared and double-stained specimens from early stage embryos to adults. In general, our results show that the morphogenesis of the vertebral column in E. johnstonei recapitulates the ancestral tadpole-like pattern of development. However, the analysis of the sequence of events using heterochrony plots shows important heterocronies relative to metamorphic species, such as a delay in the chondrification of the vertebral centra and in osteogenesis. These ontogenetic peculiarities may represent derived traits in direct-developing frogs and are possibly correlated with its unusual life history. In addition, several features of the vertebral column of E. johnstonei are highly variable from its typical morphology. We report some malformations and small deviations, which do not seem to affect the survival of individuals. These anomalies have also been found in other frogs, and include many vertebral defects, such as vertebral fusion, and vertebral preclusion and/or induction.


Assuntos
Anuros/crescimento & desenvolvimento , Coluna Vertebral/crescimento & desenvolvimento , Fatores Etários , Animais , Anuros/embriologia , Biomarcadores/análise , Larva/crescimento & desenvolvimento , Metamorfose Biológica , Morfogênese , Osteogênese , Coluna Vertebral/química , Coluna Vertebral/embriologia
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