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1.
Tropical evergreen forests of Indian subcontinent, especially of the Western Ghats, are known hot spots of amphibian diversity, where many new anuran species await to be identified. Here we describe from the Sharavathi River basin of central Western Ghats a new shrub-frog taxon related to the anuran family Rhacophoridae. The new frog possesses the characteristic features of rhacophorids (dilated digit tips with differentiated pads circumscribed by a complete groove, intercalary cartilages on digits, T-shaped terminal phalanges and granular belly, the adaptive characters for arboreal life forms), but also a suite of unique features that distinguish it from all known congeners in the region. Morphogenetic analysis based on morphological characteristics and diversity in the mitochondrial 12S and 16S rRNA genes revealed it to be a new Philautus species that we named Philautus neelanethrus sp. nov. The phylogenetic analysis suggests the new frog to represent a relatively early Philautus species lineage recorded from the region. The distribution pattern of the species suggests its importance as a bioindicator of habitat health. In general, this relatively widespread species was found distributed only in non-overlapping small stretches, which indirectly indicates the fragmentation of the evergreen to moist deciduous forests that characterize the Western Ghats. Thus the discovery of the new rhacophorid species described here not only further reinforces the significance of the Western Ghats as a major hotspot of amphibian biodiversity, but also brings into focus the deterioration of forest habitats in the region and the need for prioritization of their conservation.  相似文献   

2.
The study of current distribution patterns of amphibian species in South America is of particular interest in areas such as evolutionary ecology and conservation biology. These patterns could be playing an important role in biological interactions, population size, and connectivity, and potential extinction risk in amphibians. Here, we tested the effects of spatial and environmental factors on the variation, turnover, and phylogenetic diversity of anuran amphibian species in tropical forests of western Ecuador. Data for presence/absence of 101 species of 34 genera and 10 families registered in 12 sites (nested in four biogeographic units) were obtained through fieldwork, museum collections, and literature records. We examined the influence of geographical, altitudinal, temperature, and precipitation distances on differences in anuran composition between sites. We found significant positive correlations among all of these variables with anuran distribution. The greatest alpha diversity (species richness) was found in the Equatorial Chocó biogeographic unit. Equatorial Pacific biogeographic unit could act as a transition zone between the Equatorial Chocó and Equatorial Tumbes. The western Andes (Western Cordillera biogeographic unit) was the most dissimilar and exhibited a higher species turnover rate than the other biogeographic units. Our results suggest that precipitation and elevation play a key role in maintaining the diversity of amphibian species in western Ecuador.  相似文献   

3.
Ten leaves from each of 13 different tree types from two differentrainforest sites in North Queensland, Australia were examined in order toestablish the fungal diversity developing on these leaves. A total of 57microfungi were identified, most of which were mitosporic fungi. Speciesdiversity in terms of richness and evenness were compared and the Mt Lewis sitewas found to be richer as compared to the Butchers Creek site. Statisticalmeasurements of diversity indices, however, showed that the two forest siteswere of similar diversity. Thirty-six of the fungi identified occurred only onone leaf type, indicating possible host specificities or recurrences. The samplesize, however, is deemed to be insufficient, as a larger sample size may haveresulted in less of the fungi appearing to be host specific. It is recommendedthat future studies should include more leaf samples and less tree types. It isparticularly important that the same leaf species are collected within the samesite and at different sites in order to establish the effects of host on fungalcomposition.  相似文献   

4.

Background  

The forests of the upper Amazon basin harbour some of the world's highest anuran species richness, but to date we have only the sparsest understanding of the distribution of genetic diversity within and among species in this region. To quantify region-wide genealogical patterns and to test for the presence of deep intraspecific divergences that have been documented in some other neotropical anurans, we developed a molecular phylogeny of the wide-spread terrestrial leaflitter frog Eleutherodactylus ockendeni (Leptodactylidae) from 13 localities throughout its range in Ecuador using data from two mitochondrial genes (16S and cyt b; 1246 base pairs). We examined the relation between divergence of mtDNA and the nuclear genome, as sampled by five species-specific microsatellite loci, to evaluate indirectly whether lineages are reproductively isolated where they co-occur. Our extensive phylogeographic survey thus assesses the spatial distribution of E. ockendeni genetic diversity across eastern Ecuador.  相似文献   

5.
Aim This study assessed changes in diversity and assemblage composition in bryophytes and their associated invertebrates along altitudinal gradients in Australia and New Zealand. The importance of altitude in shaping these communities and for the diversity of both invertebrates and bryophytes was examined at different spatial scales, including local, altitudinal, regional and biogeographical. Location Samples were taken from four Australasian mountain ranges between 42° and 43°S: Mt Field and Mt Rufus, Tasmania, Australia, and Otira Valley and Seaward Kaikoura Mountains, South Island, New Zealand. Methods On both Tasmanian mountains, five altitudes were assessed (250, 500, 750, 1000 and 1250 m). At each location (mountain/altitude combination) two sites were chosen and six samples were taken. Six altitudes were assessed on New Zealand mountains (Otira: 250, 500, 750, 1000, 1250 and 1500 m; Kaikoura: 1130, 1225, 1325, 1425, 1525 and 2000 m). Bryophyte substrate was collected, and all samples were stored in 70% ethanol. Invertebrates were extracted from bryophytes using kerosene‐phase separation and all invertebrates were identified to family. At each location in Tasmania, all bryophyte species within six 25‐cm2 grids per site were collected and identified to species. Bryophytes from New Zealand were identified to species from the invertebrate sample substrate because of sampling constraints. Results Altitude did have a significant effect on diversity, however, no general trend was found along the altitudinal gradient on the four mountains. There were distinct differences in diversity between biogeographical regions, mountains, altitudes and sites. In Tasmania, Mt Field had the highest diversity in invertebrates and bryophytes at 750 m. In contrast, Mt Rufus had consistent low invertebrate and bryophyte diversity along the entire altitudinal gradient. There were also distinctive differences between locations in the composition of invertebrate and bryophyte communities in Tasmania. Along the two altitudinal gradients in New Zealand, Otira had highest diversity for both invertebrates and bryophytes at low altitudes, whereas Kaikoura had highest invertebrate and lowest bryophyte diversity at the highest altitude. Main conclusions There was an effect of altitude, however, there were no consistent changes in diversity or composition on the four different mountains. There was considerable local and regional variation, and, despite a strong sampling design, no underlying altitudinal trends were detectable. This study demonstrates the importance of examining a range of spatial scales if patterns in community structure along altitudinal gradients are to be studied. The implications of this study are discussed with reference to survey design, taxonomic resolution, climate change and conservation of habitat.  相似文献   

6.
无尾两栖动物的鸣声通常具有物种特异性,了解其鸣声特征信息,是利用生物声学进行物种多样性调查及物种监测的前提。本文汇总、整理了2012–2020年间利用高保真录音设备在野外记录的43种(隶属于7科26属)无尾两栖动物的鸣声数据,以及相应的鸣声采集信息。对音频文件进行降噪处理后,提供了由61个鸣声的波形图及语图组成的鸣声特征数据集。本数据集展示了鸣声的多种时域和频域信息,如单音节或多音节、音节数、音节时长、音节间隔、鸣声时长、主频、基频、谐波等,为我国无尾两栖类的声学研究、物种多样性调查及鸣声监测提供了数据支持。  相似文献   

7.
Direct development has evolved in rhacophorine frogs independently from other anuran lineages, thereby offering an opportunity to assess features associated with this derived life history. Using a developmental series of the direct-developing Philautus silus (Ranidae: Rhacophorinae) from Sri Lanka, we examine features of cranial morphology that are part of a suite of adaptations that facilitate feeding in free-living tadpoles, but have been changed or lost in other direct-developing lineages. Larval-specific upper jaw cartilages, which are absent from many non-rhacophorine direct-developing species (such as Eleutherodactylus coqui), develop in embryos of P. silus. Similarly, lower jaw cartilages initially assume a larval morphology, which is subsequently remodeled into the adult jaw configuration before hatching. However, the cartilaginous jaw suspension and hyobranchial skeleton never assume a typical larval morphology. The palatoquadrate, which suspends the lower jaw, lacks the posterior connections to the braincase found in many metamorphosing species. Unlike in metamorphosing species, bone formation in P. silus begins before hatching. However, the sequence of bone formation resembles that of metamorphosing anurans more than that of other direct developers. In particular, P. silus does not exhibit precocious ossification of the lower jaw, which is characteristic of some frogs and caecilians that lack a free-living tadpole. These data reveal some similarities between Philautus and other direct-developing anurans. However, the departure of Philautus embryos from the generalized tadpole skeletal morphology is less pronounced than that observed in other direct-developing taxa.  相似文献   

8.
One hundred and sixty plots, approximately every 100 m above sea level (a.s.1.) along an altitudinal gradient from 470 to 3 080 m a.s.1, at the southern and northern watershed of Mt. Shennongjia, China, were examined to determine the altitudinal pattern of plant species diversity. Mt. Shennongjia was found to have high plant species diversity, with 3 479 higher plants recorded. Partial correlation analysis and detrended canonical correspondence analysis (DCCA) based on plant species diversity revealed that altitude was the main factor affecting the spatial pattern of plant species diversity on Mt. Shennongjia and that canopy coverage of the arbor layer also had a considerable effect on plant species diversity. The DCCA based on species data of importance value further revealed that altitude gradient was the primary factor shaping the spatial pattern of plant species. In addition, the rule of the “mid-altitude bulge” was supported on Mt. Shennongjia. Plant species diversity was closely related to vegetation type and the transition zone usually had a higher diversity. Higher plant species diversity appeared in the mixed evergreen and deciduous broadleaved forest zone (900-1500 m a.s.1.) and its transition down to evergreen broadleaved forest zone or up to deciduous broadleaved forest zone. The largest plant species diversity in whole communities on Mt. Shennongjia lay at approximately 1 200 m a.s.1. Greatest tree diversity, shrub diversity, and grass diversity was found at approximately 1 500, 1 100, and 1 200 m a.s.l., respectively. The southern watershed showed higher plant species diversity than the northern watershed, with maximum plant species diversity at a higher altitude in the southern watershed than the northern watershed. These results indicate that Mt. Shennongjia shows characteristics of a transition region. The relationship between the altitudinal pattern of plant species diversity and the vegetation type in eastern China are also discussed and a hypothesis about the altitudinal pattern of plant species diversity in eastern China is proposed.  相似文献   

9.
Several amphibian species have ecological traits that can make them vulnerable to landscape changes, such as habitat preference and reproductive strategies. We evaluated how anuran species and their respective reproductive modes were distributed in an Atlantic Forest fragmented landscape, Southeastern Brazil. We sampled through visual encounter surveys three continuous forest sites, 12 forest fragments and five pasture areas (matrix) between July 2007 and March 2010. We recorded 50 anuran species with 15 reproductive modes, a third of them (33.3%) recorded only in continuous forest sites (modes 3, 8, 19, 25 and 36). These reproductive modes found only in continuous forest sites are typically forest‐associated, and seem to be more vulnerable to habitat loss. Additionally, we found a trend for larger fragments to harbor both higher number of types of reproductive sites and diversity of frog reproductive modes. Our findings suggests that fragment sizes can better predict the number of frog reproductive modes than the species richness in Atlantic Forest fragmented landscapes, and highlights the need to consider frog reproductive traits in future studies.  相似文献   

10.
We studied anuran assemblage composition from 1st to 4th orders along two rivers in the Rio Preto State Park, southeastern Brazil. We aimed to understand how species distribution relates to local features/longitudinal gradients within a river, and to differences between rivers. We assessed climatic (temperature, humidity), chemical (water pH, dissolved oxygen, conductivity), physical (river bottom type, current), and biotic (vegetation structure) features thought to affect anuran distribution. Cluster analyses showed that species assemblages tended to be more similar among sections of the same river than between corresponding sections of different rivers, and Mantel tests showed assemblages to be spatially structured, although river features were not. The river with a mixture of open vegetation and forest at its margins sheltered higher species diversity than the one bordered by forest. Using Canonical Correspondence Analyses, we found variables related to microhabitat availability to be the best ones to explain species distribution in the adult stage, and conductivity to be the best one for the tadpole stage. The river seasonal flood pulse seems to influence availability of additional reproductive sites and tadpole dispersal. We found no evidence of gradients of tadpole abundance responding to river size or predator abundance. Considering that anuran species are spatially structured and influenced by variables that change both locally and regionally, we recommend that the whole longitudinal gradient along permanent lotic ecosystems, together with its original limnological and structural attributes, is preserved in order to ensure conservation of anuran diversity in both local and regional scales.  相似文献   

11.
Colombia hosts the second highest amphibian species diversity on Earth, yet its fauna remains poorly studied, especially using molecular genetic techniques. We present the results of the first wide-scale DNA barcoding survey of anurans of Colombia, focusing on a transect across the Eastern Cordillera. We surveyed 10 sites between the Magdalena Valley to the west and the eastern foothills of the Eastern Cordillera, sequencing portions of the mitochondrial 16S ribosomal RNA and cytochrome oxidase subunit 1 (CO1) genes for 235 individuals from 52 nominal species. We applied two barcode algorithms, Automatic Barcode Gap Discovery and Refined Single Linkage Analysis, to estimate the number of clusters or “unconfirmed candidate species” supported by DNA barcode data. Our survey included ~7% of the anuran species known from Colombia. While barcoding algorithms differed slightly in the number of clusters identified, between three and ten nominal species may be obscuring candidate species (in some cases, more than one cryptic species per nominal species). Our data suggest that the high elevations of the Eastern Cordillera and the low elevations of the Chicamocha canyon acted as geographic barriers in at least seven nominal species, promoting strong genetic divergences between populations associated with the Eastern Cordillera.  相似文献   

12.
测定了4个种(红蹼树蛙、黑蹼树蛙、白斑小树蛙和红吸盘小树蛙)共11个种群的16S rRNA基因片段。双斑树蛙、马来棱皮树蛙、越南棱皮树蛙以及日本溪树蛙的同源序列通过GenBank检索获得。去除所有插入、缺失及模糊位点后,比对序列长度为500bp,其中变异位点115个,简约信息位点92个。以日本溪树蛙为外群,运用Bayesian法、MP法和ML法构建了系统发育树。结果表明红蹼树蛙和白斑小树蛙在种级水平上均不是单系。红蹼树蛙海南种群与双斑树蛙亲缘关系更近,并且来自云南不同地理种群的红蹼树蛙可以分为两大支系;越南棱皮树蛙与红吸盘小树蛙聚为一支,马来棱皮树蛙嵌套在白斑小树蛙不同地理种群中。进而认为白斑小树蛙是马来棱皮树蛙的同物异名,建议将红吸盘小树蛙并入棱皮树蛙属。  相似文献   

13.
Most megadiversity regions lack basic wild animal diversity information such as species lists. This absence of basic knowledge restricts the development and effectiveness of conservation action plans, which are urgently needed for animal groups such as amphibians, the most threatened vertebrate group in the world. In this study, we estimated Brazilian anuran diversity based on species range distribution shapes and evaluated factors that likely affect species lists, such as current taxonomy knowledge, current number of specimens collected in each region, biome characteristics, and anuran size (snout–vent length). We were able to demonstrate differences among the distributional patterns of species within each biome and each Brazilian federative state and among certain factors that influence their diversity, such as latitudinal variation. In this integrative study, we provide zoogeographic information about the richest (in terms of anuran biodiversity) country in the world (at least 849 described species, about 60% of which are endemic), which may be fundamental to future conservation actions in Brazil.  相似文献   

14.
15.
Mount Hilong-hilong is a key biodiversity area, spanning several municipalities in the provinces of the Caraga Region(Agusan del Norte, Agusan del Sur, Surigao del Norte and Surigao del Sur), northeastern Mindanao Island, southern Philippines. The Hilong-hilong massif remains one of the most significant forested areas in Mindanao, threatened with habitat modification(forest removal, degradation) and other anthropogenic disturbances related to renewable resource extraction. Amphibians are key indicator species for environmental quality and are useful focal taxa for conservation efforts. Relying on historical museum database information and new survey work on Mount Hilonghilong, we provide species accounts and describe microhabitat preferences of the anurans(frogs and toads) present in the area. Twenty-seven species representing seven anuran families were studied in detail at elevations between 700 to 1300 meters above sea level; 16 of these species are Mindanao faunal region endemics. Qualitative overlap in microhabitat use was observed, suggesting that, for the species recorded, intact forest may ensure species persistence to some levels of anthropogenic disturbance. A more extensive herpetofaunal survey is needed to fully estimate the herpetofaunal diversity of Mount Hilong-hilong. Because amphibians represent fine-scale indicators of environmental quality and microendemism, we recommend appropriate fine-scaled regional strategies geared towards the conservation of amphibians in the Caraga area, northeast Mindanao Island.  相似文献   

16.
The spatial distribution of species has long sparked interest among ecologists and biogeographers, increasingly so in studies of species responses to climate change. However, field studies on spatial patterns of distribution, useful to inform conservation actions at local scales, are still lacking for many regions, especially the tropics. We studied elevational trends and species‐area relationships among anurans in wetland habitats within Volcanoes National Park (VNP) in Rwanda, part of the biodiverse Albertine Rift region. In VNP, wetlands are key sites for anuran reproduction, and anurans are likely threatened by wetland desiccation which has occurred for the last few decades. Between 2012 and 2017, we sampled anuran communities in ten VNP wetlands located along an elevational gradient of c. 600 m (from 2,546 to 3,188 m a.s.l.) and found at least eight species, including at least two Albertine Rift Endemics. We show that species richness, diversity, and abundance likely decline with a decrease in wetland size and with an increase in elevation, though additional sampling (e.g., at night) might be needed to derive definite conclusions. Larger wetlands at lower elevations contained most species and individuals, which indicates the potential threat of wetland size reduction (through desiccation) for anuran conservation. However, we also found that wetlands differed in species composition and that some species (e.g., Sclerophrys kisoloensis) were likely restricted in distribution to only a few of the smaller wetlands—suggesting that the conservation of each individual wetland should be prioritized, regardless of size. We propose that all wetlands in VNP require additional conservation measures, which should be based on knowledge gathered through long‐term monitoring of anuran communities and research on drivers of wetland decline. Only such extended research will allow us to understand the response of anurans in VNP to threats such as climate change and wetland desiccation.  相似文献   

17.
Mount (Mt) Elgon forest in western Kenya is important for biodiversity, environmental protection and socio‐economic development. Characterizing forest conditions is essential for evaluation of sustainable management and conservation activities. This paper covers findings of a study which determined and analysed indicators useful in monitoring disturbance levels in the Mt Elgon Forest. A systematic survey was carried out and covered 305 plots of 0.02 ha and 250 smaller nested regeneration plots along 10 belt transects that were distributed in five blocks within the moist lower montane forest type. Collected and analysed data include types of disturbance, tree species composition, abundance and logged species. Correlation breakdown among disturbance types revealed that, paths were indicators of the number of tree harvesting sites (rs =1.00, P < 0.01) and of de‐vegetated areas through grass harvesting (rs = 0.90, P = 0.04). Solanum mauritianum Scop. was an indicator of old‐charcoal production sites. Logging targeted 13 tree species and harvested trees with diameter at breast height above 20 cm. The most exploited species were Olea capensis L. and Deinbolia kilimandscharica Taub. All exploited species had low regeneration but tree regeneration was not an effective indicator of logging.  相似文献   

18.
Phylogenetic relationships among representative species of the family Rhacophoridae were investigated based on 2904bp of sequences from both mitochondrial (12S rRNA, 16S rRNA, the complete t-RNA for valine), and nuclear (tyrosinase, rhodopsin) genes. Maximum parsimony, maximum likelihood, and Bayesian analyses were employed to reconstruct the phylogenetic trees. This analysis, combined with previous phylogenetic studies, serves as a framework for future work in rhacophorid systematics. The monophyly of Rhacophorus is strongly confirmed except for the species R.hainanus, which is the sister taxon to A.odontotarsus. The non-monophyly of the newly designated genus Aquixalus by Delorme et al. [Delorme, M., Dubois, A., Grosjean, S., Ohler, A., 2005. Une nouvelle classification générique et subgénérique de la tribu des Philautini (Amphibia, Anura, Ranidae, Rhacophorinae). Bull. Mens. Soc. Linn. Lyon 74, 165-171] is further confirmed. Aquixalus (Aquixalus) forms a well-supported monophyletic group within Kurixalus, whereas, Aquixalus (Gracixalus) is more closely related to species of Rhacophorus, Polypedates, and Chiromantis. Philautus as currently understood, does not form a monophyletic group. Philautus (Kirtixalus) is the sister group to the clade comprising Kurixalus and Aquixalus (Aquixalus), and more remotely related to Philautus (Philautus). Chiromantisromeri does not cluster with species of Chiromantis, and forms a basal clade to all rhacophorids save Buergeria. We propose some taxonomic changes that reflect these findings, but further revision should await more detailed studies, which include combined morphological and molecular analyses, with greater species sampling.  相似文献   

19.
20.
高黎贡山地区属于全球生物多样性热点地区之一。长期以来,受地形复杂且植被浓密等限制,对该地区生物多样性现状缺乏全面深入的调查。2013年11月至2015年9月期间,通过布设红外相机,我们对云南高黎贡山国家级自然保护区西坡怒江州泸水县片马区域的兽类和鸟类多样性进行了初步调查,试图进一步补充该区域鸟兽多样性本底资料。调查期内共监测了41个不同相机位点,累计9,503个相机日,拍摄到808组独立有效照片。经鉴定包括兽类21种和鸟类24种,分属于10目21科38属,其中怒江金丝猴Rhinopithecus strykeri是近年来在高黎贡山地区新发现的灵长类动物。灵长目、肉食目、偶蹄目、雀形目、鸡形目和啮齿目等类群的相对多样性指数较高,且分布广泛。进一步对7种丰富度较高物种的出现时间段分析发现:(1)熊猴Macacaassamensis、怒江金丝猴和血雉Ithaginis cruentus的日活动规律峰值出现在上午和下午;(2)橙腹长吻松鼠Dremomys lokriah和紫啸鸫Myophonus caeruleus的日活动高峰出现在中午,但前者在黄昏活动相对较多;(3)黄喉貂Martes flavigula和野猪Sus scrofa具有一定的夜行性,但野猪的夜行性更强。本研究提供了高黎贡山中段西坡兽类和鸟类多样性现状的基础数据,有助于今后深入研究和推进本地区生物多样性保护。  相似文献   

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