Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Assunto da revista
País de afiliação
Intervalo de ano de publicação
1.
Proc Natl Acad Sci U S A ; 121(11): e2318857121, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38437547

RESUMO

Warning coloration and Batesian mimicry are classic examples of Darwinian evolution, but empirical evolutionary patterns are often paradoxical. We test whether foraging costs predict the evolution of striking coloration by integrating genetic and ecological data for aposematic and mimetic snakes (Elapidae and Dipsadidae). Our phylogenetic comparison on a total of 432 species demonstrated that dramatic changes in coloration were well predicted by foraging strategy. Multiple tests consistently indicated that warning coloration and conspicuous mimicry were more likely to evolve in species where foraging costs of conspicuous appearance were relaxed by poor vision of their prey, concealed habitat, or nocturnal activity. Reversion to crypsis was also well predicted by ecology for elapids but not for dipsadids. In contrast to a theoretical prediction and general trends, snakes' conspicuous coloration was correlated with secretive ecology, suggesting that a selection regime underlies evolutionary patterns. We also found evidence that mimicry of inconspicuous models (pitvipers) may have evolved in association with foraging demand for crypsis. These findings demonstrate that foraging is an important factor necessary to understand the evolution, persistence, and diversity of warning coloration and mimicry of snakes, highlighting the significance of additional selective factors in solving the warning coloration paradox.


Assuntos
Mimetismo Biológico , Baixa Visão , Humanos , Filogenia
2.
Zoolog Sci ; 37(6): 586-594, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33269875

RESUMO

The red-bellied form of Calliophis intestinalis (Laurenti, 1768) sensu lato was originally reported from Pahang, west Malaysia. To determine the taxonomic status of this form, we examined the type specimens of Elaps sumatranus Lidth De Jeude, 1890, Calliophis intestinalis everetti (Boulenger, 1896), and Callophis furcatus var. nigrotaeniatus Peters, 1863. The results indicated that the red-bellied form of C. intestinalis should be named as Calliophis nigrotaeniatus comb. nov., whose valid species status was based on morphological and molecular analyses. We designate a lectotype and redescribe the species, which is genetically close to Calliophis bilineatus (Peters, 1881) from the Philippines, and is clearly distinguishable from other congeners by possessing a pair of gray or dark blue lateral stripes and by being bright red on the ventrum. Elaps sumatranus and C. i. everetti are relegated to subjective junior synonyms of C. nigrotaeniatus.


Assuntos
Elapidae/classificação , Animais , Elapidae/anatomia & histologia , Elapidae/genética , Feminino , Genes Mitocondriais , Masculino , Filogenia , Análise de Sequência de DNA , Especificidade da Espécie
3.
Sci Rep ; 14(1): 2575, 2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38297026

RESUMO

The South China giant salamander, Andrias sligoi, is one of the largest extant amphibian species worldwide. It was recently distinguished from another Chinese species, the Chinese giant salamander, Andrias davidianus, which is considered Critically Endangered according to the International Union for Conservation of Nature (IUCN) Red List. It appears too late to save this extremely rare and large amphibian in situ. Another extant species of the same genus, Andrias japonicus, inhabits Japan. However, the introduction of Chinese giant salamanders into some areas of Japan has resulted in hybridization between the Japanese and Chinese species. During our genetic screening of giant salamanders in Japan, we unexpectedly discovered four individuals of the South China giant salamander: two were adult males in captivity, and one had recently died. The last individual was a preserved specimen. In this study, we report these extremely rare individuals of A. sligoi in Japan and discuss the taxonomic and conservational implications of these introduced individuals.


Assuntos
Espécies em Perigo de Extinção , Urodelos , Humanos , Animais , Urodelos/genética , Anfíbios , China , Japão
4.
Zootaxa ; 4926(4): zootaxa.4926.4.4, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33756730

RESUMO

We found a uniquely colored dicroglossid frog of the genus Occidozyga from western Sarawak, East Malaysia. It is divergent from other congeners in morphology and mtDNA sequences. In a molecular phylogeny, this species is the sister lineage to the continental species O. lima and O. martensii with weak support. The species is small with SVL 16-18 mm in males and 18-19 mm in females, without dorsolateral fold but with transverse wrinkles on dorsum, tips of fingers lacking disks but of toes with disks, only first and second toes webbed to disks, and orange-brown dorsum with dark brown band. We thus describe it as a new species.


Assuntos
Anuros , DNA Mitocondrial , Animais , Anuros/genética , Bornéu , DNA Mitocondrial/genética , Feminino , Malásia , Masculino , Filogenia
5.
Sci Rep ; 10(1): 12670, 2020 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-32728121

RESUMO

The jaws of vertebrates display a striking diversity in form and function, but they typically open and close like a trapdoor rather than sliding like a saw. Here, we report unique feeding behaviour in the blunt-headed snail-eating snake, Aplopeltura boa (family Pareidae), where the snake cuts off and circumvents the indigestible part (the operculum) of its prey in the mouth using long sliding excursions of one side of the mandible, while the upper jaws and the mandible on the other side maintain a stable grasp on the prey. This behaviour, which we call 'mandibular sawing', is made possible by extraordinarily independent movements of the jaw elements and is a surprising departure from usual feeding behaviour in vertebrates.


Assuntos
Colubridae/fisiologia , Comportamento Alimentar/fisiologia , Mandíbula/anatomia & histologia , Animais , Comportamento Animal , Colubridae/anatomia & histologia , Mandíbula/fisiologia , Caramujos
6.
Zootaxa ; 4661(3): zootaxa.4661.3.6, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31716700

RESUMO

We collected a specimen of a scincid lizard of Larutia Böhme, 1981 from the edge of a primary forest on Gunung Penrissen, Kuching Division, Sarawak, Malaysian Borneo. The single specimen of the new species differs from all other known congeners by the molecular divergence in the mitochondrial ND1 gene and morphological characters including small adult body size (SVL 84 mm); 22 longitudinal scale rows around midbody; first pair of chinshields contacting second infralabial; second pair of chinshields separated from infralabials by an elongated scale; two subdigital lamellae on second toe; and body without yellow or pale bands or spots. It is the ninth species described in the genus and the second species of Larutia in Borneo.


Assuntos
Lagartos , Distribuição Animal , Estruturas Animais , Animais , Tamanho Corporal , Bornéu , Malásia , Filogenia
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa