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1.
Mol Phylogenet Evol ; : 108223, 2024 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-39481463

RESUMO

The genus Sylvirana includes 12 species widely distributed in South China and Southeast Asia. The phylogenetic relationships and species diversity for Sylvirana and allied genera remain unresolved and controversial due to insufficient data and incomplete taxon sampling. Using a combined dataset of mitochondrial genes (16S and COI) and 101 nuclear genes obtained through the amplicon sequence capture approach, we generated the most comprehensive phylogenetic analysis for the genus Sylvirana to date, inferring diversity, phylogenetic relationships, and historical biogeography with unprecedented levels of taxon and geographic sampling. Our results conservatively reveal six undescribed species, mostly distributed in peninsular Indochina. Phylogenetic analyses strongly support the non-monophyly of Sylvirana with respect to Pterorana. Additionally, phylogenetic results place Sylvirana guentheri and Pelophylax lateralis into genus Humerana, supporting the inclusion of Hylarana latouchii, Papurana milleti, and Hylarana attigua within Pterorana + Sylvirana. The long-disputed species of Hylarana bannanica (previously Sylvirana) cluster with genus Papurana. Because the results of multiple non-monophyletic genera create taxonomic confusion, we suggest relegating all genera to subgenus rank of Hylarana. Sylvirana is a junior synonym of the Pterorana. Biogeographically, we trace the origin of Pterorana to Southeast Asia during the early Miocene, with subsequent dispersal thereafter. Our study shows that climatic changes may have profoundly influenced the diversification of Pterorana during the Miocene.

2.
Proc Natl Acad Sci U S A ; 121(20): e2320674121, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38684007

RESUMO

Identifying and protecting hotspots of endemism and species richness is crucial for mitigating the global biodiversity crisis. However, our understanding of spatial diversity patterns is far from complete, which severely limits our ability to conserve biodiversity hotspots. Here, we report a comprehensive analysis of amphibian species diversity in China, one of the most species-rich countries on Earth. Our study combines 20 y of field surveys with new molecular analyses of 521 described species and also identifies 100 potential cryptic species. We identify 10 hotspots of amphibian diversity in China, each with exceptional species richness and endemism and with exceptional phylogenetic diversity and phylogenetic endemism (based on a new time-calibrated, species-level phylogeny for Chinese amphibians). These 10 hotspots encompass 59.6% of China's described amphibian species, 49.0% of cryptic species, and 55.6% of species endemic to China. Only four of these 10 hotspots correspond to previously recognized biodiversity hotspots. The six new hotspots include the Nanling Mountains and other mountain ranges in South China. Among the 186 species in the six new hotspots, only 9.7% are well covered by protected areas and most (88.2%) are exposed to high human impacts. Five of the six new hotspots are under very high human pressure and are in urgent need of protection. We also find that patterns of richness in cryptic species are significantly related to those in described species but are not identical.


Assuntos
Anfíbios , Biodiversidade , Filogenia , Animais , Anfíbios/classificação , China , Conservação dos Recursos Naturais
3.
Conserv Biol ; 37(6): e14155, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37551770

RESUMO

Although numerous studies on the impacts of climate change on biodiversity have been published, only a handful are focused on the intraspecific level or consider population-level models (separate models per population). We endeavored to fill this knowledge gap relative to the Qinghai-Tibetan plateau (QTP) by combining species distribution modeling (SDMs) with population genetics (i.e., population-level models) and phylogenetic methods (i.e., phylogenetic tree reconstruction and phylogenetic diversity analyses). We applied our models to 11 endemic and widely distributed herpetofauna species inhabiting high elevations in the QTP. We aimed to determine the influence of environmental heterogeneity on species' responses to climate change, the magnitude of climate-change impacts on intraspecific diversity, and the relationship between species range loss and intraspecific diversity losses under 2 shared socioeconomic pathways (SSP245 and SSP585) and 3 future periods (2050s, 2070s, and 2090s). The effects of global climatic change were more pronounced at the intraspecific level (22% of haplotypes lost and 36% of populations lost) than the morphospecies level in the SSP585 climate change scenario. Maintenance of genetic diversity was in general determined by a combination of factors including range changes, species genetic structure, and the part of the range predicted to be lost. This is owing to the fact that the loss and survival of populations were observed in species irrespective of the predicted range changes (contraction or expansion). In the southeast (mountainous regions), climate change had less of an effect on range size (>100% in 3 species) than in central and northern QTP plateau regions (range size <100% in all species). This may be attributed to environmental heterogeneity, which provided pockets of suitable climate in the southeast, whereas ecosystems in the north and central regions were homogeneous. Generally, our results imply that mountainous regions with high environmental heterogeneity and high genetic diversity may buffer the adverse impacts of climate change on species distribution and intraspecific diversity. Therefore, genetic structure and characteristics of the ecosystem may be crucial for conservation under climate change.


Impactos del cambio climático sobre la diversidad de herpetofauna en la meseta Qinghai-Tíbet Región Aunque se han publicado numerosos estudios sobre los impactos del cambio climática en la biodiversidad, son muy pocos los que se enfocan en el nivel intraespecífico o que consideran modelos a nivel poblacional (modelos separados por población). Intentamos cerrar este vacío de conocimiento en relación con la meseta Qinghai-Tíbet (MQT) con la combinación entre modelos de distribución de especies (MDE) y genética poblacional (modelos a nivel poblacional) y métodos filogenéticos (reconstrucción de árboles filogenéticos y análisis de diversidad filogenética). Aplicamos nuestros modelos a once especies endémicas de herpetofauna con distribución amplia en las elevaciones más altas de la MQT. Nos planteamos determinar la influencia de la heterogeneidad de las especies sobre la respuesta de las especies al cambio climático, la magnitud de los impactos del cambio climático sobre la diversidad intraespecífica y la relación entre la pérdida de distribución de la especie y las pérdidas de diversidad intraespecífica bajo dos vías socioeconómicas (SSP245 y SSP585) y tres periodos del futuro (2050s, 2070s y 2090s). Los efectos del cambio climático global fueron más pronunciados a nivel intraespecífico (22% de pérdida en los haplotipos y 36% en las poblaciones) que al nivel morfoespecie en el escenario de cambio climático SSP585. El mantenimiento de la diversidad genética casi siempre estuvo determinado por una combinación de factores que incluyen cambios en la distribución, estructura genética de las especies y la parte de la distribución que se pronosticó se perdería. Esto se debe a que observamos la pérdida y supervivencia de las poblaciones sin importar los cambios pronosticados en la distribución (contracción o expansión). En las regiones montañosas del sureste, el cambio climático tuvo un efecto menor sobre la distribución (>100% en tres especies) comparado con las regiones de la meseta central y del norte de la MQT (distribución <100% en todas las especies). Esto puede atribuirse a la heterogeneidad ambiental, la cual proporciona recovecos de clima adecuado en el sureste, mientras que los ecosistemas en las regiones central y norte fueron homogéneos. De manera general, nuestros resultados implican que las regiones montañosas con una elevada heterogeneidad ambiental y una gran diversidad genética podrían reducir los impactos adversos del cambio climático sobre la distribución de las especies y la diversidad intraespecífica. Por lo tanto, la estructura genética y las características del ecosistema pueden ser cruciales para conservar bajo el cambio climático.


Assuntos
Mudança Climática , Ecossistema , Tibet , Filogenia , Conservação dos Recursos Naturais
4.
Mol Ecol Resour ; 23(5): 1124-1141, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36924341

RESUMO

DNA barcoding has greatly facilitated studies of taxonomy, biodiversity, biological conservation, and ecology. Here, we establish a reliable DNA barcoding library for Chinese snakes, unveiling hidden diversity with implications for taxonomy, and provide a standardized tool for conservation management. Our comprehensive study includes 1638 cytochrome c oxidase subunit I (COI) sequences from Chinese snakes that correspond to 17 families, 65 genera, 228 named species (80.6% of named species) and 36 candidate species. A barcode gap analysis reveals gaps, where all nearest neighbour distances exceed maximum intraspecific distances, in 217 named species and all candidate species. Three species-delimitation methods (ABGD, sGMYC, and sPTP) recover 320 operational taxonomic units (OTUs), of which 192 OTUs correspond to named and candidate species. Twenty-eight other named species share OTUs, such as Azemiops feae and A. kharini, Gloydius halys, G. shedaoensis, and G. intermedius, and Bungarus multicinctus and B. candidus, representing inconsistencies most probably caused by imperfect taxonomy, recent and rapid speciation, weak taxonomic signal, introgressive hybridization, and/or inadequate phylogenetic signal. In contrast, 43 species and candidate species assign to two or more OTUs due to having large intraspecific distances. If most OTUs detected in this study reflect valid species, including the 36 candidate species, then 30% more species would exist than are currently recognized. Several OTU divergences associate with known biogeographic barriers, such as the Taiwan Strait. In addition to facilitating future studies, this reliable and relatively comprehensive reference database will play an important role in the future monitoring, conservation, and management of Chinese snakes.


Assuntos
Biodiversidade , Código de Barras de DNA Taxonômico , Humanos , Animais , Filogenia , Código de Barras de DNA Taxonômico/métodos , Serpentes/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética
5.
Curr Zool ; 69(1): 82-90, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36974146

RESUMO

Species delimitation is essential to informing conservation policy and understanding ecological and evolutionary processes. Most of our recent gains in knowledge on animal diversity rely on morphological characteristics and mitochondrial (mt) DNA variation. Concordant results based on both have led to an unprecedented acceleration in the identification of new species and enriched the field of taxonomy. However, discordances are also found commonly between morphological and mtDNA evidence. This confounds species delimitation, especially when gene flow or mt genome introgression has occurred. Here, we illustrate how mt genome introgression among species of the Odorrana grahami complex confounds species delimitation using the combined evidence of morphological characters, mt variation, and thousands of nuclear single-nucleotide polymorphisms (SNPs) from genotyping-by-sequencing (GBS). Fifty-eight samples across the distribution of the O. grahami complex were included. The mtDNA matrilineal genealogy indicated 2 clades, with O. grahami and Odorrana junlianensis clustered together. In contrast, all nuclear evidence including gene trees, species trees, and genetic structure analyses based on GBS data support 3 species with distinct genetic clusters. These 3 distinct genetic clusters also correspond to distinct morphological characters. They affirm the distinct taxonomic entities of both O. grahami and O. junlianensis, as well as a third clade distinct from either. Which species the third clade belongs to remains unclear and will require further testing. The nuclear genomic loci contradict the COI evidence, with indications of rampant historical mt genome introgression among the species of the O. grahami complex. These discordant signals previously confused species delimitation efforts in this group. Based on these findings, we recommend the integration of independent data, especially nuclear genomic evidence, in species delimitation so as to be robust against the pitfalls of mt introgression.

6.
Biodivers Data J ; 11: e103580, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38327331

RESUMO

Background: To date, 10 species of the genus Microhyla have been recorded in China, of which six were distributed in Yunnan Province. Microhylahmongorum Hoang, Nguyen, Phan, Pham, Ninh, Wang, Jiang, Ziegler, and Nguyen, 2022 was also speculated to be distributed in Xishuangbana, Yunnan Province, China. However, there is no evidence of documentation of M.hmongorum. New information: We report the first country record of Microhylahmongorum, based on specimens collected from Yunnan border region. Morphologically, the specimen was consistent with the original descriptions of M.hmongorum. Phylogenetically, the sequences of the specimens from China clustered with the sequence of type specimens of M.hmongorum from Vietnam, with uncorrected pairwise distances of 0.9% at the 16S gene fragment analysed. Therefore, we report M.hmongorum as a new record species in China.

7.
Proc Natl Acad Sci U S A ; 119(46): e2212406119, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36346846

RESUMO

Defense against ultraviolet (UV) radiation exposure is essential for survival, especially in high-elevation species. Although some specific genes involved in UV response have been reported, the full view of UV defense mechanisms remains largely unexplored. Herein, we used integrated approaches to analyze UV responses in the highest-elevation frog, Nanorana parkeri. We show less damage and more efficient antioxidant activity in skin of this frog than those of its lower-elevation relatives after UV exposure. We also reveal genes related to UV defense and a corresponding temporal expression pattern in N. parkeri. Genomic and metabolomic analysis along with large-scale transcriptomic profiling revealed a time-dependent coordinated defense mechanism in N. parkeri. We also identified several microRNAs that play important regulatory roles, especially in decreasing the expression levels of cell cycle genes. Moreover, multiple defense genes (i.e., TYR for melanogenesis) exhibit positive selection with function-enhancing substitutions. Thus, both expression shifts and gene mutations contribute to UV adaptation in N. parkeri. Our work demonstrates a genetic framework for evolution of UV defense in a natural environment.


Assuntos
Anuros , Raios Ultravioleta , Animais , Anuros/genética , Pele , Perfilação da Expressão Gênica , Antioxidantes
8.
Zool Res ; 43(3): 469-480, 2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35514224

RESUMO

Effective conservation of threatened biota relies on accurate assessments and scientific guidance. As an unfortunate example, Chinese giant salamanders ( Andrias, CGS) remain critically endangered in nature. Misguided conservation efforts, e.g., commercial propagation and releasing of millions of likely non-indigenous or interspecific hybrids, have further compromised conservation initiatives. Limited information on wild populations of CGS poses a significant conservation challenge. Following 18-month long field monitoring, we now report the discovery of a wild population of CGS in a closed nature reserve in Jiangxi Province, China. Genomic assessments reveal its genetic distinctiveness and do not detect genetic admixture with other species. Based on morphological and molecular evidences, we describe this CGS as a new species Andrias jiangxiensis sp. nov. This is the only known species of CGS today with a genetically pure, reproducing, in situ population. This discovery emphasizes the important role that closed nature reserves play in protecting species, and the necessity of integrating long-term field monitoring and genetic assessments. It sets a new pathway for discovering and conserving endangered species, especially for those biotas that are similarly being extirpated by anthropogenic translocations and overexploitation.


Assuntos
Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Animais , China , Urodelos/genética
9.
Mol Biol Evol ; 39(4)2022 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-35356979

RESUMO

Speciation plays a central role in evolutionary studies, and particularly how reproductive isolation (RI) evolves. The origins and persistence of RI are distinct processes that require separate evaluations. Treating them separately clarifies the drivers of speciation and then it is possible to link the processes to understand large-scale patterns of diversity. Recent genomic studies have focused predominantly on how species or RI originate. However, we know little about how species persist in face of gene flow. Here, we evaluate a contact zone of two closely related toad-headed lizards (Phrynocephalus) using a chromosome-level genome assembly and population genomics. To some extent, recent asymmetric introgression from Phrynocephalus putjatai to P. vlangalii reduces their genomic differences. However, their highly divergent regions (HDRs) have heterogeneous distributions across the genomes. Functional gene annotation indicates that many genes within HDRs are involved in reproduction and RI. Compared with allopatric populations, contact areas exhibit recent divergent selection on the HDRs and a lower population recombination rate. Taken together, this implies that divergent selection and low genetic recombination help maintain RI. This study provides insights into the genomic mechanisms that drive RI and two species persistence in the face of gene flow during the late stage of speciation.


Assuntos
Genética Populacional , Lagartos , Animais , Fluxo Gênico , Especiação Genética , Hibridização Genética , Lagartos/genética , Recombinação Genética , Isolamento Reprodutivo
10.
Natl Sci Rev ; 8(9): nwaa263, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34691726

RESUMO

The Himalaya are among the youngest and highest mountains in the world, but the exact timing of their uplift and origins of their biodiversity are still in debate. The Himalayan region is a relatively small area but with exceptional diversity and endemism. One common hypothesis to explain the rich montane diversity is uplift-driven diversification-that orogeny creates conditions favoring rapid in situ speciation of resident lineages. We test this hypothesis in the Himalayan region using amphibians and reptiles, two environmentally sensitive vertebrate groups. In addition, analysis of diversification of the herpetofauna provides an independent source of information to test competing geological hypotheses of Himalayan orogenesis. We conclude that the origins of the Himalayan herpetofauna date to the early Paleocene, but that diversification of most groups was concentrated in the Miocene. There was an increase in both rates and modes of diversification during the early to middle Miocene, together with regional interchange (dispersal) between the Himalaya and adjacent regions. Our analyses support a recently proposed stepwise geological model of Himalayan uplift beginning in the Paleocene, with a subsequent rapid increase of uplifting during the Miocene, finally giving rise to the intensification of the modern South Asian Monsoon.

11.
Mol Phylogenet Evol ; 163: 107218, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34082130

RESUMO

Montane frogs of the genus Quasipaa Dubois, 1992 occur from southern China to Southeast Asia (Frost 2021). Analyses of mtDNA (Cytb) and nuDNA data (Rag1, Rag2, Rhod, Tyr) for samples from 93 localities throughout its distribution yield a phylogeny. Clades A and B occur in Southeast Asia, clade C in northern Yangtze River, China, clade D in southwestern China, and clades E and F in southeastern China. Results place Q. yei within monophyletic Quasipaa and identify two new species. Based on nuDNA data, the basal split of clade A and B indicates an Indochinese origin of Quasipaa. The west-east diversification of five species across South China (Q. spinosa, Q. exilispinosa, Q. jiulongensis, Q. shini, Q. boulengeri) corresponds to topographic terrains II and III of China. Divergence of species from southeastern China (Q. shini, Q. jiulongensis, Q. spinosa, Q. exilispinosa) and southwestern China (Q. boulengeri) dates to 15.30-16.56 Ma (million years ago). A principal component analysis (PCA) and t-test involving 19 bioclimatic variables identifies significantly different environmental conditions between the two regions. Species' distribution models (SDM) for Q. spinosa and Q. boulengeri identify the best areas to be eastern and western South China, respectively. Thus, environmental variation appears to have influenced the genetic divergence and distributions of Quasipaa in South China. Mito-nuclear discordance indicates that some individuals of Q. exilispinosa and Q. spinosa hybridized historically.


Assuntos
Anuros , DNA Mitocondrial , Animais , Anuros/genética , Núcleo Celular , China , DNA Mitocondrial/genética , Humanos , Filogenia
12.
Zootaxa ; 4941(1): zootaxa.4941.1.1, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33756946

RESUMO

Recent studies have highlighted the underestimated diversity of the genus Diploderma Hallowell, 1861 in the Hengduan Mountain Region in Southwest China, but much of the region remains poorly surveyed for reptile diversity. In this study we describe two new species of Diploderma from the upper Jinsha and middle Yalong River Valley, based on evaluations of morphological, genetic, and distribution data. The two new species are morphologically most similar to D. angustelinea and D. vela, but they can be diagnosed from both recognized taxa and all remaining congeners by a suite of morphological features, particularly the distinct coloration of gular spots. Additionally, both new species either render other recognized species paraphyletic or are allopatric with respect to their morphologically similar congeners. Furthermore, we rediscover D. brevicaudum in the wild for the first time, which was known from historical museum specimens only. We estimate the phylogenetic position of D. brevicaudum within the genus Diploderma based on mitochondrial genealogy, and we provide an expanded diagnosis and comparisons against closely related congeners and provide a detailed description of coloration in life based on newly collected specimens. Our discoveries of the new Diploderma species further highlight the urgent conservation needs of the currently neglected hot-dry valley ecosystems in the Hengduan Mountain Region of China.


Assuntos
Ecossistema , Lagartos , Animais , China , Filogenia , Serpentes
14.
Cell Res ; 30(8): 693-701, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32581344

RESUMO

Despite the substantial role that chickens have played in human societies across the world, both the geographic and temporal origins of their domestication remain controversial. To address this issue, we analyzed 863 genomes from a worldwide sampling of chickens and representatives of all four species of wild jungle fowl and each of the five subspecies of red jungle fowl (RJF). Our study suggests that domestic chickens were initially derived from the RJF subspecies Gallus gallus spadiceus whose present-day distribution is predominantly in southwestern China, northern Thailand and Myanmar. Following their domestication, chickens were translocated across Southeast and South Asia where they interbred locally with both RJF subspecies and other jungle fowl species. In addition, our results show that the White Leghorn chicken breed possesses a mosaic of divergent ancestries inherited from other subspecies of RJF. Despite the strong episodic gene flow from geographically divergent lineages of jungle fowls, our analyses show that domestic chickens undergo genetic adaptations that underlie their unique behavioral, morphological and reproductive traits. Our study provides novel insights into the evolutionary history of domestic chickens and a valuable resource to facilitate ongoing genetic and functional investigations of the world's most numerous domestic animal.


Assuntos
Galinhas/genética , Genoma , Filogenia , Distribuição Animal , Animais , Animais Domésticos/genética , Ásia , Domesticação , Pool Gênico , Geografia , Funções Verossimilhança , Aves Domésticas/genética , Seleção Genética
15.
Oncol Lett ; 19(3): 2339-2345, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32194733

RESUMO

The present study aimed to investigate the role of long noncoding RNA MACC1-AS1 in cervical squamous cell carcinoma (CSCC). In the present study MACC1-AS1 expression as analyzed using reverse transcription-quantitative PCR. The interactions between MACC1-AS1 and miR-34a was analyzed via overexpression experiments. Cell cycle and proliferation analyses were performed to analyze the roles of MACC1-AS1 in regulating cancer cell cycle progression and cell proliferation. It was observed that MACC1-AS1 was upregulated in CSCC, and its expression levels were elevated with the increase in clinical stage. Bioinformatics analysis revealed that MACC1-AS1 may be a sponge of miR-34a, which can target cyclin-dependent kinase 6 (CDK6). In CSCC cells, MACC1-AS1 overexpression led to upregulation of CDK6, while miR-34a overexpression had the opposite effect and reduced the effects of MACC1-AS1 overexpression in co-transfected cells. Cell cycle and proliferation analyses demonstrated that MACC1-AS1 and CDK6 promoted cell cycle progression and cell proliferation. By contrast, miR-34a had the opposite effect on cell cycle proliferation and cell proliferation, reducing the effects induced by MACC1-AS1 overexpression. Therefore, the lncRNA MACC1-AS1 may serve as a sponge of miR-34a to upregulate CDK6, thereby promoting cell cycle progression and cell proliferation.

16.
Mol Phylogenet Evol ; 145: 106724, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31881327

RESUMO

Rhacophoridae are one of the most speciose and ecologically diverse families of amphibians. Resolution of their evolutionary relationships is key to understanding the accumulation of biodiversity, yet previous hypotheses based on Sanger sequencing exhibit much discordance amongst generic relationships. This conflict precludes the making of sound macroevolutionary conclusions. Herein, we conduct the first phylogenomic study using broad-scale sampling and sequences of 352 nuclear DNA loci obtained using anchored hybrid enrichment targeted sequencing. The robust time-calibrated phylogenetic hypothesis clarifies several long-disputed relationships and facilitates the testing of evolutionary hypotheses on spatiotemporal diversification and reproductive modes. The major extant lineages of Rhacophoridae appear to have radiated in mainland Asia, and the spatiotemporal process corresponds with several common accumulations of biodiversity in Asia. Analyses do not detect any case of "Out of Himalaya" in Rhacophoridae. All transitions of reproductive modes appear to have evolved in an ordered, gradual sequence associated with gaining independence of standing water for larval development. The different reproductive modes are phylogenetically conserved and the completion of their transitions appear to have occurred over a period of ~30 Ma, which does not fit a pattern of a rapid burst of diversification. Innovations in reproductive modes associate statistically with the uneven distribution of species-richness between clades, where higher diversification is linked to increased terrestrial modes of reproduction. These results strengthen the hypothesis that breeding innovations drive diversification by providing new opportunities for ecological release and dispersion.


Assuntos
Anuros/classificação , Evolução Biológica , Animais , Anuros/genética , Anuros/crescimento & desenvolvimento , Teorema de Bayes , Biodiversidade , Núcleo Celular/genética , Filogenia , Filogeografia , Reprodução
17.
Curr Zool ; 65(6): 713-724, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31857818

RESUMO

Nigeria is an Afrotropical region with considerable ecological heterogeneity and levels of biotic endemism. Among its vertebrate fauna, reptiles have broad distributions, thus, they constitute a compelling system for assessing the impact of ecological variation and geographic isolation on species diversification. The red-headed rock agama, Agama agama, lives in a wide range of habitats and, thus, it may show genetic structuring and diversification. Herein, we tested the hypothesis that ecology affects its genetic structure and population divergence. Bayesian inference phylogenetic analysis of a mitochondrial DNA (mtDNA) gene recovered four well-supported matrilines with strong evidence of genetic structuring consistent with eco-geographic regions. Genetic differences among populations based on the mtDNA also correlated with geographic distance. The ecological niche model for the matrilines had a good fit and robust performance. Population divergence along the environmental axes was associated with climatic conditions, and temperature ranked highest among all environmental variables for forest specialists, while precipitation ranked highest for the forest/derived savanna, and savanna specialists. Our results cannot reject the hypothesis that niche conservatism promotes geographic isolation of the western populations of Nigerian A. agama. Thus, ecological gradients and geographic isolation impact the genetic structure and population divergence of the lizards. This species might be facing threats due to recent habitat fragmentation, especially in western Nigeria. Conservation actions appear necessary.

18.
Zootaxa ; 4612(4): zootaxa.4612.4.7, 2019 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31717043

RESUMO

Herein, we describe the new agamid species Acanthosaura phongdienensis sp. nov. from central Vietnam based on morphological and genetic data. Males of the new medium-sized species have a snout-vent length of up to 77.4 mm and females up to 64.7 mm. In both genders, the tail is longer than the snout-vent length. A spine occurs on each side of the neck, the rostral scute is entire, and the nuchal and dorsal crests are continuous. A postorbital spine is about half as long as the diameter of the eye-ball, and small lateral scales intermix with large, keeled scales whose tips point backwards and upwards. The new species differs genetically from the closely related species A. brachypoda, A. coronata, and A. lepidogaster by uncorrected p-distances of 13.6%, 21.7%, and 12.8%, respectively. This is the 13th species of Acanthosaura and the eighth species in the genus from Vietnam.


Assuntos
Lagartos , Animais , Feminino , Masculino , Filogenia , Vietnã
19.
Zootaxa ; 4688(1): zootaxa.4688.1.5, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31719460

RESUMO

Little is known about the worm-eating snakes of the genus Trachischium in the East Himalaya due to their secretive nature. To date, only T. monticola and T. tenuiceps are recorded from China, and the former species was recorded based on historical literature without vouchered information. In addition, a questionable record of T. guentheri in Tibet, China exists in literature, but no one has yet confirmed this distribution record. Here we confirm the distribution of T. guentheri in southeastern Tibet, China based on a newly collected specimen, and provide the first detailed description of T. monticola, including the first description of its hemipenial morphology, based on newly collected Tibetan specimens. Lastly, we provide a diagnostic key to the three Chinese species, and discuss the general distribution patterns of the genus in the Trans-Himalayan Region.


Assuntos
Colubridae , Aves Canoras , Animais , China , Tibet
20.
Zootaxa ; 4571(4): zootaxa.4571.4.10, 2019 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-31715798

RESUMO

The China-Vietnam border region is a well-known biodiversity hotspot, harboring a striking diversity of species and endemism. However, the largest part of this region is so far understudied due to restrictions by political boundaries and difficulties in accessibility. Consequently, many species have only been reported from one side of the political boundary, despite the presence of continuous habitat on both sides. In this study, we present our discovery of the frog Nidirana chapaensis in southern Yunnan Province, China. This species was previously known only from Vietnam. All major morphometric characters of these Chinese specimens were found to match with the Vietnamese specimens. In addition, our mitochondrial phylogeny suggests that the Chinese population is monophyletic with respect to topotypic Nidirana chapaensis, with uncorrected pairwise distances of 0.2% at the COI gene fragment analyzed. Therefore, we report Nidirana chapaensis as a new member of amphibian fauna of China, describe the morphological variation of the Chinese population, and provide additional natural history data of this species based on our observation from China.


Assuntos
Anuros , Ranidae , Animais , China , Filogenia , Vietnã
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