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1.
Zootaxa ; 3785: 469-80, 2014 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-24872238

RESUMEN

We describe a new species of Philodryas from the highlands of southern Ecuador. The new species is distinguished from all known species of Philodryas by a unique combination of coloration, scalation, and hemipenial characters. The new species resembles Philodryas simonsii in color pattern. However, they differ notoriously by their hemipenial morphology. The three other trans-Andean members of the genus (Philodryas simonsii, Philodryas chamissonis, and Philodryas tachymenoides), along with the new species, compose a probably monophyletic group that may be characterized by the presence of ungrooved postdiastemal teeth in the maxilla. Unlike most species of the genus Philodryas, the new species shows a restricted distribution, being apparently endemic to a small region of high-altitude (3150-4450m) grasslands in the southern Andes of Ecuador.


Asunto(s)
Serpientes/anatomía & histología , Serpientes/clasificación , Animales , Demografía , Ecuador , Femenino , Masculino
2.
Zootaxa ; 3721: 455-74, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-26120686

RESUMEN

We describe a new species of Atractus from Cordillera de los Guacamayos in the Andes of Ecuador. This new species is the largest known species of Atractus, reaching almost 120 cm in total length with a robust habitus. We also use multivariate statistical analyses of morphometric data to look into the taxonomic confusion involving other large, banded/blotched, species of Atractus in Western Amazonia. We show that A. snethlageae has a widespread distribution in Amazonia and has been repeatedly confused with A. major in Ecuador owing to its color polymorphism. Our multivariate statistical analyses support previous suggestions to recognize A. snethlageae as a distinct species relative to A. flammigerus. Taxonomic accounts are provided for both A. major and A. snethlageae including detailed color pattern descriptions. We also find that there are no valid morphological differences to support recognizing A. arangoi as a separate species from A. major; consequently we synonymize the former name with the latter.


Asunto(s)
Colubridae/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Tamaño Corporal , Colubridae/anatomía & histología , Colubridae/crecimiento & desarrollo , Ecuador , Femenino , Hábitos , Masculino
3.
Zootaxa ; 4658(3): zootaxa.4658.3.4, 2019 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-31716732

RESUMEN

A new frog of the genus Pristimantis is described from a montane cloud forest at 9 de Octubre (2°14'52" S, 78°16'37" W; 1778 m) province of Morona Santiago in the upper basin of the Upano River, southeastern Ecuador. The description of the new species is based on the examination of eleven adult males and three adult females. The new taxon can be readily distinguished from other congeneric species that inhabit the eastern Andes of Ecuador by the unique combination of the following characters: small body (adult males SVL 12.0-17.0 mm, adult females SVL 18.5-21.7 mm); skin of dorsum finely shagreen with two subconical scapular tubercles, weak and discontinuous dorsolateral folds in the middle of the back; large tympanum 70-93% of eye diameter; snout subacuminate in dorsal view, rounded in profile; upper eyelid bearing four or five small and flat supraocular tubercles; males lacking vocal slits and nuptial pads; all discs on fingers and toes lanceolate. Additionally, we provide information on the advertisement call and natural history of the new species.


Asunto(s)
Anuros , Reproducción , Distribución Animal , Animales , Ecuador , Femenino , Masculino , Filogenia
4.
Zootaxa ; 4353(3): 447-466, 2017 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-29245497

RESUMEN

A new frog in the genus Pristimantis is described from a cloud forest on the western flanks of the Cordillera del Cóndor and eastern Andean slopes in the province of Zamora Chinchipe, southeastern of Ecuador. We inferred its phylogenetic position using DNA sequences of mitochondrial and nuclear genes. The new species is strongly supported as part of a clade that includes P. ardalonychus, P. cajamarcensis, P. ceuthospilus, P. chalceus, P. minutulus, P. luteolateralis, P. parvillus, P. ockendeni, P. unistrigatus, and P. walkeri. It can be distinguished from all other species from Cordillera del Cóndor and congeneric species by the unique combination of the following characters: (1) iris light blue with black reticulations; (2) skin of dorsum finely shagreen with scattered pustular tubercles and absence of dorsal folds; (3) tympanic membrane and tympanic annulus visible; (4) snout rounded in dorsal and lateral view; (5) upper eyelid bearing two or three enlarged subconical tubercles; (6) cranial crest absent; (7) males lacking vocal sac and slits; and (8) venter uniformly bright red, light red, salmon or orange. The new species is most closely related to P. ardalonychus, P. cajamarcensis, P. ceuthospilus, P. ockendeni and P. unistrigatus. We consider the new species to be Endangered following IUCN criteria because it has been severely affected by large scale open-pit mining in some localities. Currently, the amphibian fauna of the Cordillera del Cóndor and nearby protected areas are threatened by large-scale copper and gold mining projects with devastating effects on ~20 species, including several undescribed ones.


Asunto(s)
Anuros , Distribución Animal , Animales , Ecuador , Masculino , Filogenia
5.
Zookeys ; (661): 91-123, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28769604

RESUMEN

We present a molecular phylogeny of snake genus Atractus, with an improved taxon sampling that includes 30 of the 140 species currently recognized. The phylogenetic tree supports the existence of at least three new species in the Pacific lowlands and adjacent Andean slopes of the Ecuadorian Andes, which we describe here. A unique combination of molecular, meristic and color pattern characters support the validity of the new species. With the newly acquired data, we propose and define the Atractus iridescens species group, as well as redefine the Atractus roulei species group. The species Atractus iridescens is reported for the first time in Ecuador, whereas Atractus bocourti and Atractus medusa are removed from the herpetofauna of this country. We provide the first photographic vouchers of live specimens for Atractus multicinctus, Atractus paucidens and Atractus touzeti, along with photographs of 19 other Ecuadorian Atractus species. The current status of Atractus occidentalis and Atractus paucidens is maintained based on the discovery of new material referable to these species. With these changes, the species number reported in Ecuador increases to 27, a number that is likely to increase as material not examined in this work becomes available and included in systematic studies.

6.
PLoS One ; 10(11): e0143392, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26600198

RESUMEN

Pluralistic approaches to taxonomy facilitate a more complete appraisal of biodiversity, especially the diversification of cryptic species. Although species delimitation has traditionally been based primarily on morphological differences, the integration of new methods allows diverse lines of evidence to solve the problem. Robber frogs (Pristimantis) are exemplary, as many of the species show high morphological variation within populations, but few traits that are diagnostic of species. We used a combination of DNA sequences from three mitochondrial genes, morphometric data, and comparisons of ecological niche models (ENMs) to infer a phylogenetic hypothesis for the Pristimantis acuminatus complex. Molecular phylogenetic analyses revealed a close relationship between three new species-Pristimantis enigmaticus sp. nov., P. limoncochensis sp. nov. and P. omeviridis sp. nov.-originally confused with Pristimantis acuminatus. In combination with morphometric data and geographic distributions, several morphological characters such as degree of tympanum exposure, skin texture, ulnar/tarsal tubercles and sexual secondary characters (vocal slits and nuptial pads in males) were found to be useful for diagnosing species in the complex. Multivariate discriminant analyses provided a successful classification rate for 83-100% of specimens. Discriminant analysis of localities in environmental niche space showed a successful classification rate of 75-98%. Identity tests of ENMs rejected hypotheses of niche equivalency, although not strongly because the high values on niche overlap. Pristimantis acuminatus and P. enigmaticus sp. nov. are distributed along the lowlands of central-southern Ecuador and northern Peru, in contrast with P. limoncochensis sp. nov. and P. omeviridis sp. nov., which are found in northern Ecuador and southern Colombia, up to 1200 m in the upper Amazon Basin. The methods used herein provide an integrated framework for inventorying the greatly underestimated biodiversity in Amazonia.


Asunto(s)
Anuros , Biodiversidad , Ecosistema , Distribución Animal , Animales , Anuros/anatomía & histología , Anuros/clasificación , Anuros/genética , Modelos Teóricos , Filogenia , Filogeografía
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