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1.
We sampled Palaearctic naked‐toed geckos from across their range in India and used two mitochondrial and two nuclear genes to reconstruct relationships within a global phylogeny. Published sequences of Peninsular Indian Hemidactylus allow us to contrast these two groups in dating analyses – providing insights into the history of the Indian dry zone. Palaearctic naked‐toed geckos first moved onto the Indian Plate in the Oligocene, with higher‐level diversification probably linked to collision of the Indian and Eurasian plates, and subsequent dispersal into‐India and diversification with increasing Miocene aridity. An independent gekkonid radiation with species in the dry zone, Hemidactylus diversified during the same period in Peninsular India. Our results demonstrate that dry zone taxa across India may date back to at least the Miocene, with a potential historical climatic barrier between the Indus and Peninsular Indian Divisions. ‘Cyrtopodionaravallense is revealed to be a complex with seven genetically and environmentally divergent lineages that began diversifying in the late Miocene, congruent with increased aridity in north‐western India. This discovery of cryptic diversity in the Indian dry zone represents the first terrestrial vertebrate radiation from north‐western central India and highlights how little we understand of the regions’ biodiversity, emphasizing the need for systematic geographic sampling and multiline evidence to reveal true patterns of diversity. The ancestor of ‘Cyrtopodion’ aravallense came into the nascent Indian dry zone in the Miocene and has since diversified, potentially in the absence of any sympatric scansorial rupicolous geckos. Cyrtopodion scabrum represents a unique case of commensalism and shows phylogeographic structure in its presumed native range. The taxonomic implications of our study include a number of undescribed species, recognition of ‘Cyrtopodion’ as a distinct lineage and the non‐monophyly of Altiphylax.  相似文献   

2.
Microptila orienthula , sp. n. from Japan is described and illustrated based on adults of both sexes. The new species represents the first finding of Microptila in the Eastern Palaearctic Region, and it appears to be more closely related to Oriental species of Microptila than to the two Western Palaearctic species. The finding of a new species with affinities to the Oriental species as far northeast as Japan is noteworthy but fits well with general zoogeographical affinities of the Japanese fauna to the Oriental Region. The type locality indicates a hygropetric habitat for the larva, in agreement with the known larval habitat of the European type species Microptila minutissima Ris, 1897.  相似文献   

3.
Understanding pre‐ and post‐copulatory mechanisms of sexual selection can provide insights into the evolution of male reproductive strategies. The phenotype‐linked fertility hypothesis postulates that male sperm quality and secondary sexual characteristics will positively co‐vary, whereas the sperm competition hypothesis predicts a negative association between those traits. Male reproductive traits often show variation throughout the reproductive period, suggesting that the relationship between pre‐ and post‐copulatory sexual selection may vary temporally. Here, we evaluated the relationship between secondary sexual character and sperm traits and its temporal variation in Salvator rufescens, a south American lizard. We observed a negative relationship between jaw muscle and principal piece length of sperm and a variation in the relationship between pre‐ and post‐copulatory traits throughout the reproductive period. Collectively, our results evidenced a trade‐off between pre‐ and post‐copulatory traits and a strong seasonal flexibility of male reproductive strategies in this lizard species.  相似文献   

4.
The North American deserts were impacted by both Neogene plate tectonics and Quaternary climatic fluctuations, yet it remains unclear how these events influenced speciation in this region. We tested published hypotheses regarding the timing and mode of speciation, population structure, and demographic history of the Mojave Fringe‐toed Lizard (Uma scoparia), a sand dune specialist endemic to the Mojave Desert of California and Arizona. We sampled 109 individual lizards representing 22 insular dune localities, obtained DNA sequences for 14 nuclear loci, and found that U. scoparia has low genetic diversity relative to the U. notata species complex, comparable to that of chimpanzees and southern elephant seals. Analyses of genotypes using Bayesian clustering algorithms did not identify discrete populations within U. scoparia. Using isolation‐with‐migration (IM) models and a novel coalescent‐based hypothesis testing approach, we estimated that U. scoparia diverged from U. notata in the Pleistocene epoch. The likelihood ratio test and the Akaike Information Criterion consistently rejected nested speciation models that included parameters for migration and population growth of U. scoparia. We reject the Neogene vicariance hypothesis for the speciation of U. scoparia and define this species as a single evolutionarily significant unit for conservation purposes.  相似文献   

5.
A time‐calibrated phylogenetic tree indicates that the evolution of sympatric, montane, endemic species from closely related, co‐distributed lineages of the Hemiphyllodactylus harterti group were not the result of rapid, forest‐driven, climatic oscillations of the Last Glacial Maximum, but rather the result of infrequent episodes of environmental fluctuation during the Late Miocene. This hypothesis is supported by genetic divergences (based on the mitochondrial gene ND2) between the three major lineages of the H. harterti group (17.5–25.1%), their constituent species (9.4–14.3%), and the evolution of discrete, diagnostic, morphological, and colour pattern characteristics between each species. Sister species pairs from two of the three lineages occur in sympatry on mountain tops from opposite sides of the Thai–Malay Peninsula, but the lineages to which each pair belongs are not sister lineages. A newly discovered species from Gunung Tebu, Terengganu State, H emiphyllodactylus bintik sp. nov. , is described. © 2015 The Linnean Society of London  相似文献   

6.
Parapharyngodon kenyaensis n. sp. and Thelandros samburuensis n. sp. (Nematoda: Pharyngodonidae) from the large intestine of the agamid lizard (Agama caudospina) are described and illustrated. Parapharyngodon kenyaensis n. sp. is the 41st species assigned to the genus, and it differs from other species in that genus by possessing 3 pairs of caudal papillae, cloacal lip adornment, and spicules of 112-120 microm in length. Thelandros samburuensis n. sp. is the 31st species assigned to the genus, and it differs from other species in that genus by possessing swollen posterior annulations, 6 caudal papillae, a smooth anterior cloacal lip, and spicules of 43-52 microm in length. In addition to the 2 new nematode species, Abbreviata ortleppi (Nematoda: Physalopteridae) and Strongyluris ornata (Nematoda: Heterakidae) were found.  相似文献   

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Two dytiscid beetle species, Leiodytes nicobaricus (Redtenbacher) and Platambus stygius (Régimbart), are identified for the first time in Korea. Diagnoses, habitus and scanning electron microscopy photographs, and line drawings of the diagnostic characters are provided.  相似文献   

9.
Peripatric speciation and the importance of founder effects have long been controversial, and multilocus sequence data and coalescent methods now allow hypotheses of peripatric speciation to be tested in a rigorous manner. Using a multilocus phylogeographical data set for two species of salamanders (genus Hydromantes) from the Sierra Nevada of California, hypotheses of recent divergence by peripatric speciation and older, allopatric divergence were tested. Phylogeographical analysis revealed two divergent lineages within Hydromantes platycephalus, which were estimated to have diverged in the Pliocene. By contrast, a low‐elevation species, Hydromantes brunus, diverged from within the northern lineage of H. platycephalus much more recently (mid‐Pleistocene), during a time of major climatic change in the Sierra Nevada. Multilocus species tree estimation and coalescent estimates of divergence time, migration rate, and growth rate reject a scenario of ancient speciation of H. brunus with subsequent gene flow and introgression from H. platycephalus, instead supporting a more recent divergence with population expansion. Although the small, peripheral distribution of H. brunus suggests the possibility of peripatric speciation, the estimated founding population size of the species was too large to have allowed founder effects to be important in its divergence. These results provide evidence for both recent speciation, most likely tied to the climatic changes of the Pleistocene, and older lineage divergence, possibly due to geological events, and add to evidence that Pleistocene glacial cycles were an important driver of diversification in the Sierra Nevada.  相似文献   

10.
Next‐generation sequencing has vast potential to revolutionize the fields of phylogenetics and population genetics through its ability to collect genomic scale data sets of thousands of orthologous loci. Despite this potential, other types of data (e.g. morphology, ecology) remain important, particularly for studies endeavouring to delimit species. Here, we integrate next‐generation sequencing with morphology to examine divergence between populations of Tribolonotus pseudoponceleti on the islands of Buka and Bougainville in the Solomon Archipelago. We used the Ion Torrent PGM to collect over 648 Mbp of sequence data for 12 samples, representing 1526 loci recovered from all samples, and 3342 were recovered from at least six samples. Genetic structure analyses strongly support the distinctiveness of these two populations, and Bayes factor delimitations decisively select speciation between Buka and Bougainville. Principal components and discriminant function analyses reveal concordant morphological divergence. Finally, demographic analyses via diffusion approximation and approximate Bayesian computation prefer a complex model of mid‐Pleistocene divergence with migration, and a later decrease or cessation of migration and population size shift, suggesting a scenario in which migration was enabled by Pleistocene merging of these two islands, and limited when isolated by higher sea levels. Further analysis of four Sanger sequenced loci in IMa2 had limited power to distinguish among models including and excluding migration, but resulted in similar population size and divergence time estimates, although with much broader confidence intervals. This study represents a framework for how next‐generation sequencing and morphological data can be combined and leveraged towards validating putative species and testing demographic scenarios for speciation.  相似文献   

11.
The monophyly of the Sceloporus variabilis group is well established with five species and two species complexes, but phylogenetic relationships within species complexes are still uncertain. We studied 278 specimens in 20 terminals to sample all taxa in the “variabilis group,” including three subspecies in the “variabilis complex,” and two outgroups (Sceloporus grammicus and Sceloporus megalepidurus). We assembled an extensive morphological data set with discrete and continuous characters (distances and scale counts), including geometric morphometric data (landmark coordinates of three shapes), and a three‐marker molecular data set as well (ND4, 12S and RAG1). We conducted parsimony and Bayesian phylogenetic inferences on these data, including several partitioning and weighting schemes. We suggest elevating three subspecies to full species status. Therefore, we recommend recognition of nine species in the “variabilis group.” First, S. variabilis is sister to Sceloporus teapensis. In turn, Sceloporus cozumelae is sister to Sceloporus olloporus. These four species are a monophyletic group, which is sister to Sceloporus smithi. Finally, Sceloporus marmoratus is sister of the clade of five species. The other species in the “variabilis group” (Sceloporus chrysostictus, Sceloporus couchii and Sceloporus parvus) are a paraphyletic grade at the base of the tree. Our analyses reject the existence of the “variabilis complex.” We conducted a parsimony‐based ancestral reconstruction on body size (snout–vent length), femoral pores and dorsal scales and related morphological changes to geographic distribution of the species. Our phylogenetic hypothesis will allow best designs of comparative studies with species in the “variabilis group,” one of the earliest divergent lineages in the genus.  相似文献   

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We report the development of 17 di‐ and tetranucleotide microsatellite markers in the Yellow‐Spotted Night Lizard Lepidophyma flavimaculatum. Levels of heterozygosity ranged from 0 to 100%. Several loci also amplify in other Lepidophyma species and several species of the sister genus Xantusia. High levels of variation at some loci indicate that they will be useful for parentage assessment and population genetic studies, whereas the 15 loci that amplify across multiple Lepidophyma species suggest these will be useful in determining the origin of parthenogenetic populations.  相似文献   

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The presence of two species of Phthiraptera, Bovicola caprae (Gurlt, 1843) (Ischnocera: Bovicoliidae) and Solenopotes binipilosus (Fahrenholz, 1916) (Anoplura: Linognathidae), is reported for the first time from Pudu puda (Molina, 1782).  相似文献   

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This study records new maximum lengths and provides length–weight relationships (LWRs) for two small indigenous fishes, Corica soborna (Hamilton, 1822) and Mystus bleekeri (Day, 1877), from the Ganges River in northwestern Bangladesh. Fishes were sampled sporadically using gill nets and cast nets from August 2015 to July 2016. New maximum recorded lengths weere 5.3 cm total length (TL) for C. soborna and 17.7 cm TL for M. bleekeri. The LWRs were highly significant (p < .001) with r2 values >.958. These findings will play a significant role in the fisheries resource management.  相似文献   

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A time series of aerial censuses of Cape fur seal colonies, spanning four decades (1972–2009) and three countries (South Africa, Namibia, and Angola), was analyzed to assess spatiotemporal changes in population numbers. A weighted quantile regression approach was used to estimate trends in pup counts that were used as proxies for numbers of older animals at breeding colonies. There was a 74% increase in the number of breeding colonies over the study period, from 23 in 1973 to 40 in 2009. There was also a significant northward shift in the distribution of the breeding population. This was largely attributable to events in the northern part of the population's range coinciding with Namibia, where seal numbers declined at most colonies in the south of Namibia while several new breeding colonies developed in the northern part of Namibia and one in southern Angola. Despite range expansion and the development of new colonies, the overall size of the population in 2009 was similar to that of the early 1990s, according to the pup count models. Potential mechanisms for the observed changes, and their management implications, are discussed.  相似文献   

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