Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
2.
Genes (Basel) ; 13(6)2022 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-35741703

RESUMO

The Kokshaal racerunner, Eremias kokshaaliensis Eremchenko et Panfilov, 1999, together with other central Asian racerunner species, is included in the Eremias multiocellata complex. In the present work, for the first time, the results of the analysis of historical mitochondrial DNA (barcode) are presented and the taxonomic status and preliminary phylogenetic relationships within the complex are specified. We present, for the first time, the results of the molecular analysis using historical DNA recovered from specimens of several species of this complex (paratypes of the Kokshaal racerunner and historical collections of the Kashgar racerunner E. buechneri from Kashgaria) using DNA barcoding.


Assuntos
Lagartos , Animais , DNA Mitocondrial/genética , Lagartos/genética , Mitocôndrias/genética , Filogenia , Análise de Sequência de DNA
3.
PeerJ ; 10: e13260, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35497188

RESUMO

We present an integrative molecular and morphological study of subaquatic representatives of the genus Pseudohygrohypnum (Pylaisiaceae, Bryophyta), supplemented by distribution modelling of the revealed phylogenetic lineages. Phylogenetic analyses of nuclear and plastid datasets combined with the assemble species by automatic partitioning (ASAP) algorithm revealed eight distinct species within the traditionally circumscribed P. eugyrium and P. subeugyrium. These species are therefore yet another example of seemingly widely distributed taxa that harbour molecularly well-differentiated lineages with narrower distribution ranges. Studied accessions that were previously assigned to P. eugyrium form three clearly allopatric lineages, associated with temperate regions of Europe, eastern North America and eastern Asia. Remarkably, accessions falling under the current morphological concept of P. subeugyrium were shown to be even more diverse, containing five phylogenetic lineages. Three of these lineages occur under harsh Asian continental climates from cool-temperate to Arctic regions, while the remaining two, referred to P. subeugyrium s.str. and P. purpurascens, have more oceanic North Atlantic and East Asian distributions. Niche identity and similarity tests suggested no similarity in the distributions of the phylogenetically related lineages but revealed the identity of two East Asian species and the similarity of two pairs of unrelated species. A morphological survey confirmed the distinctness of all eight phylogenetic lineages, requiring the description of five new species. Pseudohygrohypnum appalachianum and P. orientale are described for North American and East Asian plants of P. eugyrium s.l., while P. sibiricum, P. subarcticum and P. neglectum are described for the three continental, predominantly Asian lineages of P. subeugyrium s.l. Our results highlight the importance of nontropical Asia as a center of bryophyte diversity. Phylogenic dating suggests that the diversification of subaquatic Pseudohygrohypnum lineages appeared in late Miocene, while mesophilous species of the genus split before Miocene cooling, in climatic conditions close to those where the ancestor of Pseudohygrohypnum appeared. We speculate that radiation of the P. subeugyrium complex in temperate Asia might have been driven by progressive cooling, aridification, and increases in seasonality, temperature and humidity gradients. Our results parallel those of several integrative taxonomic studies of North Asian mosses, which have resulted in a number of newly revealed species. These include various endemics from continental areas of Asia suggesting that the so-called Rapoport's rule of low diversity and wide distribution range in subpolar regions might not be applicable to bryophytes. Rather, the strong climatic oscillations in these regions may have served as a driving force of speciation and niche divergence.


Assuntos
Briófitas , Bryopsida , Filogenia , Filogeografia , Ásia Oriental , Ásia
4.
Sci Rep ; 12(1): 842, 2022 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-35039544

RESUMO

Five-toed jerboas of the subfamily Allactaginae comprise several complex taxa occurring over a wide distribution range covering a large part of the Eurasian arid belt. In this study, we employed current methods of molecular phylogenetics based on 15 nuclear genes and the mitochondrial gene cytb to revise relations and systematics within Allactaginae. We also applied species distribution modelling projected on paleo-environmental data to reconstruct the geographic patterns of speciation in Allactaginae. We elucidated the intergeneric relationships within this subfamily and clarified interspecies relations within the genus Scarturus. Moreover, our results demonstrate the species status of S. caprimulga; outline the currently understudied diversity within Orientallactaga, Allactaga, and Pygeretmus; and improve the divergence estimates of these taxa. Based on our results from modelling of geographic range fragmentation in allactagines, we suggest the dating and location of speciation events and present hypotheses regarding general habitat niche conservatism in small mammals.


Assuntos
Filogenia , Roedores/genética , Animais , Ecossistema , União Europeia , Variação Genética , Mitocôndrias/genética , Roedores/classificação , Especificidade da Espécie
5.
PeerJ ; 9: e10759, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33520475

RESUMO

The Tianshan birch mouse Sicista tianschanica is an endemic of the Central Asian mountains and has previously been shown to include several karyomorphs ("Terskey", "Talgar", "Dzungar"); however, the taxonomic status of these forms has remained uncertain. We examined the genetic variation in S. tianschanica based on historical DNA samples from museum collections, including the type series. Mitochondrial and nuclear data indicated that the species complex includes two major clades: Northern (N) and Southern (S) (cytb distance 13%). The N clade corresponds to the "Dzungar" karyomorph (Dzungar Alatau, Tarbagatay). The S clade is comprised of four lineages (S1-S4) divergent at 6-8%; the relationships among which are resolved incompletely. The S1 lineage is found in eastern Tianshan and corresponds to the nominal taxon. The S2 is distributed in central and northern Tianshan and corresponds to the "Terskey" karyomorph. The S3 is restricted to Trans-Ili Alatau and belongs to the "Talgar" karyomorph. The S4 is represented by a single specimen from southeastern Dzungar Alatau with "Talgar" karyotype. No interlineage gene flow was revealed. The validity of S. zhetysuica (equivalent to the N clade) is supported. Based on genetic and karyotypic evidence, lineages S2 and S3 are described as distinct species. The status of the S4 requires further investigation.

6.
Zootaxa ; 4834(4): zootaxa.4834.4.2, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-33056103

RESUMO

In the first half of the 20th century, four Swedish expeditions to Indochina contributed significantly to the knowledge on the herpetofauna of mainland Southeast Asia. The collected material was examined by L. G. Andersson in Stockholm, resulting in the description of seven new species and forms of amphibians and reptiles from Vietnam and Thailand. However, the taxonomic status of three enigmatic frog species described by Andersson, namely Rana scutigera, Oxyglossus laevis var. vittata, and Microhyla fusca, remained doubtful. All three taxa are only known from their type specimens and their short original descriptions. Though subsequent studies have doubted their validity or systematic assignment, they have been treated as valid species until today. We have examined the external morphology and coloration of the type specimens, what led to a taxonomic reallocation of these three species. We demonstrate that Rana scutigera Andersson, 1916 is a junior synonym of Polypedates megacephalus Hallowell, 1861, Oxyglossus laevis var. vittata Andersson, 1942 is synonymized with Occidozyga martensii (Peters, 1967), and Microhyla fusca Andersson, 1942 represents a junior synonym of Microhyla butleri Boulenger, 1900.


Assuntos
Anuros , Ranidae , Animais
7.
PeerJ ; 8: e9411, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32685285

RESUMO

Frogs of the genus Microhyla include some of the world's smallest amphibians and represent the largest radiation of Asian microhylids, currently encompassing 50 species, distributed across the Oriental biogeographic region. The genus Microhyla remains one of the taxonomically most challenging groups of Asian frogs and was found to be paraphyletic with respect to large-sized fossorial Glyphoglossus. In this study we present a time-calibrated phylogeny for frogs in the genus Microhyla, and discuss taxonomy, historical biogeography, and morphological evolution of these frogs. Our updated phylogeny of the genus with nearly complete taxon sampling includes 48 nominal Microhyla species and several undescribed candidate species. Phylogenetic analyses of 3,207 bp of combined mtDNA and nuDNA data recovered three well-supported groups: the Glyphoglossus clade, Southeast Asian Microhyla II clade (includes M. annectens species group), and a diverse Microhyla I clade including all other species. Within the largest major clade of Microhyla are seven well-supported subclades that we identify as the M. achatina, M. fissipes, M. berdmorei, M. superciliaris, M. ornata, M. butleri, and M. palmipes species groups. The phylogenetic position of 12 poorly known Microhyla species is clarified for the first time. These phylogenetic results, along with molecular clock and ancestral area analyses, show the Microhyla-Glyphoglossus assemblage to have originated in Southeast Asia in the middle Eocene just after the first hypothesized land connections between the Indian Plate and the Asian mainland. While Glyphoglossus and Microhyla II remained within their ancestral ranges, Microhyla I expanded its distribution generally east to west, colonizing and diversifying through the Cenozoic. The Indian Subcontinent was colonized by members of five Microhyla species groups independently, starting with the end Oligocene-early Miocene that coincides with an onset of seasonally dry climates in South Asia. Body size evolution modeling suggests that four groups of Microhyla have independently achieved extreme miniaturization with adult body size below 15 mm. Three of the five smallest Microhyla species are obligate phytotelm-breeders and we argue that their peculiar reproductive biology may be a factor involved in miniaturization. Body size increases in Microhyla-Glyphoglossus seem to be associated with a burrowing adaptation to seasonally dry habitats. Species delimitation analyses suggest a vast underestimation of species richness and diversity in Microhyla and reveal 15-33 undescribed species. We revalidate M. nepenthicola, synonymize M. pulverata with M. marmorata, and provide insights on taxonomic statuses of a number of poorly known species. Further integrative studies, combining evidence from phylogeny, morphology, advertisement calls, and behavior will result in a better systematic understanding of this morphologically cryptic radiation of Asian frogs.

8.
Zookeys ; 888: 133-158, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31754323

RESUMO

The first genetic study of the holotype of the Gansu short-tailed shrew, Blarinella griselda Thomas, 1912, is presented. The mitochondrial analysis demonstrated that the type specimen of B. griselda is close to several recently collected specimens from southern Gansu, northern Sichuan and Shaanxi, which are highly distinct from the two species of Asiatic short-tailed shrews of southern Sichuan, Yunnan, and Vietnam, B. quadraticauda and B. wardi. Our analysis of four nuclear genes supported the placement of B. griselda as sister to B. quadraticauda / B. wardi, with the level of divergence between these two clades corresponding to that among genera of Soricinae. A new generic name, Parablarinella, is proposed for the Gansu short-tailed shrew. Karyotypes of Parablarinella griselda (2n = 49, NFa = 50) and B. quadraticauda (2n = 49, NFa = 62) from southern Gansu are described. The tribal affinities of Blarinellini and Blarinini are discussed.

9.
Zookeys ; (748): 97-129, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29674917

RESUMO

The morphological and genetic variation of a wide-ranging Secret Toad-headed agama, Phrynocephalus mystaceus that inhabits sand deserts of south-eastern Europe, Middle East, Middle Asia, and western China is reviewed. Based on the morphological differences and high divergence in COI (mtDNA) gene sequences a new subspecies of Ph. mystaceus is described from Khorasan Razavi Province in Iran. Partial sequences of COI mtDNA gene of 31 specimens of Ph. mystaceus from 17 localities from all major parts of species range were analyzed. Genetic distances show a deep divergence between Ph. mystaceus khorasanusssp. n. from Khorasan Razavi Province and all other populations of Ph. mystaceus. The new subspecies can be distinguished from other populations of Ph. mystaceus by a combination of several morphological features. Molecular and morphological analyses do not support the validity of other Ph. mystaceus subspecies described from Middle Asia and Caspian basin. Geographic variations in the Ph. mystaceus species complex and the status of previously described subspecies were discussed.

10.
PeerJ ; 6: e4543, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29576991

RESUMO

We hypothesize the phylogenetic relationships of the agamid genus Phrynocephalus to assess how past environmental changes shaped the evolutionary and biogeographic history of these lizards and especially the impact of paleogeography and climatic factors. Phrynocephalus is one of the most diverse and taxonomically confusing lizard genera. As a key element of Palearctic deserts, it serves as a promising model for studies of historical biogeography and formation of arid habitats in Eurasia. We used 51 samples representing 33 of 40 recognized species of Phrynocephalus covering all major areas of the genus. Molecular data included four mtDNA (COI, ND2, ND4, Cytb; 2,703 bp) and four nuDNA protein-coding genes (RAG1, BDNF, AKAP9, NKTR; 4,188 bp). AU-tests were implemented to test for significant differences between mtDNA- and nuDNA-based topologies. A time-calibrated phylogeny was estimated using a Bayesian relaxed molecular clock with nine fossil calibrations. We reconstructed the ancestral area of origin, biogeographic scenarios, body size, and the evolution of habitat preference. Phylogenetic analyses of nuDNA genes recovered a well-resolved and supported topology. Analyses detected significant discordance with the less-supported mtDNA genealogy. The position of Phrynocephalus mystaceus conflicted greatly between the two datasets. MtDNA introgression due to ancient hybridization best explained this result. Monophyletic Phrynocephalus contained three main clades: (I) oviparous species from south-western and Middle Asia; (II) viviparous species of Qinghai-Tibetan Plateau (QTP); and (III) oviparous species of the Caspian Basin, Middle and Central Asia. Phrynocephalus originated in late Oligocene (26.9 Ma) and modern species diversified during the middle Miocene (14.8-13.5 Ma). The reconstruction of ancestral areas indicated that Phrynocephalus originated in Middle East-southern Middle Asia. Body size miniaturization likely occurred early in the history of Phrynocephalus. The common ancestor of Phrynocephalus probably preferred sandy substrates with the inclusion of clay or gravel. The time of Agaminae radiation and origin of Phrynocephalus in the late Oligocene significantly precedes the landbridge between Afro-Arabia and Eurasia in the Early Miocene. Diversification of Phrynocephalus coincides well with the mid-Miocene climatic transition when a rapid cooling of climate drove progressing aridification and the Paratethys salinity crisis. These factors likely triggered the spreading of desert habitats in Central Eurasia, which Phrynocephalus occupied. The origin of the viviparous Tibetan clade has been associated traditionally with uplifting of the QTP; however, further studies are needed to confirm this. Progressing late Miocene aridification, the decrease of the Paratethys Basin, orogenesis, and Plio-Pleistocene climate oscillations likely promoted further diversification within Phrynocephalus. We discuss Phrynocephalus taxonomy in scope of the new analyses.

11.
Zool Stud ; 57: e60, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-31966300

RESUMO

Sergei V. Kruskop, Evgeniya N. Solovyeva, and Anna D. Kaznadzey (2018) Despite huge progress in the systematics of bats and, in particular, of the Vespertilionidae family in latest years, the taxonomic position of a number of remarkable bat species has been uncertain until now, partly because of limits in acceptable comparative material. Researchers have previously placed the Malayan noctule, Pipistrellus stenopterus, into Nyctalus, because of similar body shape and proportions, or into Pipistrellus, based on karyological analysis. This study reassesses Pipistrellus stenopterus using available collection material and compares it to various members of Nyctalus and Pipistrellus, as well as with some other related and similar genera, based on respective morphological and molecular genetic features. This species demonstrates vast morphological peculiarities compared to other Pipistrellus-like bats. Nonetheless, both mitochondrial and nuclear genetic markers unequivocally place it close to other Asian pipistrelles, most probably in a sister position to the "javanicus" species group. We propose establishing P. stenopterus as a separate subgenus, Alionoctula. Our results also confirm that Pipistrellus is paraphyletic in its current state, and we suggest that further studies explore its internal taxonomy and limits.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...