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1.
J Dev Biol ; 11(2)2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37367476

RESUMO

Osteoderms are bony structures that develop within the dermal layer of the skin in vertebrates and are very often found in different lizard families. Lizard osteoderms are diverse in topography, morphology, and microstructure. Of particular interest are the compound osteoderms of skinks, which are a complex of several bone elements known as osteodermites. We present new data on the development and regeneration of compound osteoderms based on the results of a histological and Computed Microtomography (micro-CT) study of a scincid lizard: Eurylepis taeniolata. The specimens studied are stored in the herpetological collections of the Saint-Petersburg State University and Zoological Institute of the Russian Academy of Sciences located in St. Petersburg, Russia. The topography of osteoderms in the integuments of the original tail area and its regenerated part was studied. A comparative histological description of the original and regenerated osteoderms of Eurylepis taeniolata is presented for the first time. The first description of the development of compound osteoderm microstructure in the process of caudal regeneration is also presented.

2.
Zootaxa ; 5369(3): 336-368, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-38220710

RESUMO

We provide a diversity assessment of Iranian species of the genus Eremias based on the cytochrome oxidase I mtDNA gene fragment. We analyzed 93 genetic samples from the entire distribution of the Eremias fasciata species complex in Iran and surrounding regions, along with morphological data to support the description of two new species from Central Iran. We hypothesize that the diversification of the Eremias fasciata species complex was largely influenced by the fragmentation of sand massifs in the region. This same hypothesis has been used to explain the high level of endemism among the sand-dwelling species of reptiles along the Iranian Plateau in the same area. The two new species described herein can be distinguished from other congeneric species by their phylogenetic position and a combination of morphological characters. We use these data to discuss the taxonomy of Eremias based on morphology, habitat choice, and genetic data.


Assuntos
Lagartos , Animais , Irã (Geográfico) , Filogenia , DNA Mitocondrial/genética
3.
Animals (Basel) ; 13(15)2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37570324

RESUMO

The high level of endemism in Fergana Valley has been well documented in numerous studies for various groups of animals and plants. In a relatively small area, there are 45 endemic plant species, five endemic insect species, and five endemic reptile species. In surveying this area for data on distribution, abundance, acoustics, and genetic samples for species of reptiles, we discovered two new species of gecko from the genus Alsophylax. Phylogenetic analyses of mitochondrial DNA sequences indicate the relatives of these new species are the even-fingered gecko, Alsophylax pipiens, and the southern even-fingered gecko, Alsophylax laevis, located hundreds of kilometers to the northwest and southwest of the Fergana Valley. The threats to these new endemic species are significant given the amount of continued agricultural development that involves new territories previously considered "unsuitable" for any species of significance that is leading to the further reduction in, fragmentation of, and degradation of the remaining natural ecosystems in the Fergana Valley. The conservation of these rare and locally endemic species depends directly on the readiness of the state to create areas with IUCN I and II protection. The many studies documenting levels of endemism, along with the data published in this study, are the basis for the justification for state-protected areas in the Fergana Valley.

4.
Mol Phylogenet Evol ; 61(2): 400-12, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21767655

RESUMO

Eremias, or racerunners, is a widespread lacertid genus occurring in China, Mongolia, Korea, Central Asia, Southwest Asia and Southeast Europe. It has been through a series of taxonomic revisions, but the phylogenetic relationships among the species and subgenera remain unclear. In this study, a frequently studied region of the mitochondrial 16S rRNA was used to (i) reassess the phylogenetic relationships of some Eremias species, (ii) test if the viviparous species form a monophyletic group, and (iii) estimate divergence time among lineages using a Bayesian relaxed molecular-clock approach. The resulting phylogeny supports monophyly of Eremias sensu Szczerbak and a clade comprising Eremias, Acanthodactylus and Latastia. An earlier finding demonstrating monophyly of the subgenus Pareremias is corroborated, with Eremias argus being the sister taxon to Eremias brenchleyi. We present the first evidence that viviparous species form a monophyletic group. In addition, Eremias przewalskii is nested within Eremias multiocellata, suggesting that the latter is likely a paraphyletic species or a species complex. Eremias acutirostris and Eremias persica form a clade that is closely related to the subgenus Pareremias. However, the subgenera Aspidorhinus, Scapteira, and Rhabderemias seem not to be monophyletic, respectively. The Bayesian divergence-time estimation suggests that Eremias originated at about 9.9 million years ago (with the 95% confidence interval ranging from 7.6 to 12 Ma), and diversified from Late Miocene to Pleistocene. Specifically, the divergence time of the subgenus Pareremias was dated to about 6.3 million years ago (with the 95% confidence interval ranging from 5.3 to 8.5 Ma), which suggests that the diversification of this subgenus might be correlated with the evolution of an East Asian monsoon climate triggered by the rapid uplift of the Tibetan Plateau approximately 8 Ma.


Assuntos
DNA Mitocondrial/genética , Evolução Molecular , Lagartos/genética , Filogenia , RNA Ribossômico 16S/genética , Animais , Ásia , Teorema de Bayes , Europa (Continente) , Genes de RNAr , Lagartos/classificação , Modelos Genéticos , Análise de Sequência de DNA
5.
Zootaxa ; 4457(1): 93-113, 2018 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-30314181

RESUMO

In the present study we provide evidence for the validity of the genus Trigonodactylus Hass, 1957, improve the diagnosis for this genus and describe a new species that belongs to it-Trigonodactylus persicus sp. nov., from the sand dunes in Khuzestan Province, southwestern Iran. The new species is closely related to Trigonodactylus [Stenodactylus] arabicus sensu Hass, and can be distinguished by the following morphological characteristics: small size, maximum SVL 34 mm; SVL/TailL-approximately 1:1; ventral scales roundish, weakly keeled, 54-61 longitudinal rows at midbody and 190-25 along midbody. No enlarged postmentals. Fingers and toes slightly flattened dorso-ventrally. Lateral edge of digits fringed by series of projecting triangular scales. No web between digits. No preanal and femoral pores. Dorsal color pattern formed by thin, dark, irregular vermicular patches and spots. Sometimes these dark dorsal patterns blend with each other and form transverse bands. There is a narrow, dark, longitudinal line between forelimbs and hindlimbs on lateral sides. Dark, well developed ʌ-shaped marking on snout, which continues behind orbit on tympanum region, approaches the upper ear opening and ends on the pectoral arch. Labial scales white, in some cases with grey-brown dots. Dorsal surfaces of limbs and digits with irregular dark bands. Dorsal surface of tail with 8-10 wide, dark brown bands with irregular margins, same size as alternating light bands. Ventral surface of body and limbs white, tail with dark spots that become more distinct posteriorly.


Assuntos
Lagartos , Estruturas Animais , Animais , Tamanho Corporal , Ecossistema , Meio Ambiente , Irã (Geográfico)
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