68 research outputs found
New Species of Nyctibatrachus (Anura: Ranidae) from Castle Rock, Karnataka State, Southwest India
A new species of ranid frog of the genusNyctibatrachusis described from Castle Rock,Karnataka State, Southwest India. The new species is compared with all known congeners and is diagnosedby the following combination of characters: head wider than long; snout projecting beyond mouth;supratympanic fold poorly defined; webbing on toes reaching base of disks except on Toe IV, where it reachesdistal subarticular tubercle; tips of digits on fingers and toes flattened to form disks with distinct groovesseparating dorsum of disks from venter; and femoral gland present. The largest specimen in the type serieshas a snout-vent length of 43.2 mm.Nyctibatrachus hussainiKrishnamurthy, Reddy and Gururaja, 2001, isshown to be an invalid nomen, for lack of typification
A new species of the genus \u3cem\u3eThaicharmus\u3c/em\u3e KovaÅ™Ãk, 1995 (Scorpiones: Buthidae) from northeast India
A new species Thaicharmus guptai sp. nov. is described from the northeast Indian state of Tripura. The new species differs from the known members of the genus in the following set of morphological characters: large size (total length 45.6 mm); trichobothrium d2 is distal to i1 on femur; trichobothria est, em and et on the external surface of the patella do not form a straight line. Subaculear tubercle is absent. The movable finger of pedipalp chela has 12 cutting rows of denticles. The movable finger is much longer than the pedipalp patella. Number of pectinal teeth 20/19; pectines with distinct lamellae and fulcra. Two horn-like projections are present on the ventrolateral aspect of the metasomal segment V
Sex Chromosome Mosaicism and Hybrid Speciation among Tiger Swallowtail Butterflies
Hybrid speciation, or the formation of a daughter species due to interbreeding between two parental species, is a potentially important means of diversification, because it generates new forms from existing variation. However, factors responsible for the origin and maintenance of hybrid species are largely unknown. Here we show that the North American butterfly Papilio appalachiensis is a hybrid species, with genomic admixture from Papilio glaucus and Papilio canadensis. Papilio appalachiensis has a mosaic phenotype, which is hypothesized to be the result of combining sex-linked traits from P. glaucus and P. canadensis. We show that P. appalachiensis' Z-linked genes associated with a cooler thermal habitat were inherited from P. canadensis, whereas its W-linked mimicry and mitochondrial DNA were inherited from P. glaucus. Furthermore, genome-wide AFLP markers showed nearly equal contributions from each parental species in the origin of P. appalachiensis, indicating that it formed from a burst of hybridization between the parental species, with little subsequent backcrossing. However, analyses of genetic differentiation, clustering, and polymorphism based on molecular data also showed that P. appalachiensis is genetically distinct from both parental species. Population genetic simulations revealed P. appalachiensis to be much younger than the parental species, with unidirectional gene flow from P. glaucus and P. canadensis into P. appalachiensis. Finally, phylogenetic analyses, combined with ancestral state reconstruction, showed that the two traits that define P. appalachiensis' mosaic phenotype, obligatory pupal diapause and mimicry, evolved uniquely in P. canadensis and P. glaucus, respectively, and were then recombined through hybridization to form P. appalachiensis. These results suggest that natural selection and sex-linked traits may have played an important role in the origin and maintenance of P. appalachiensis as a hybrid species. In particular, ecological barriers associated with a steep thermal cline appear to maintain the distinct, mosaic genome of P. appalachiensis despite contact and occasional hybridization with both parental species
Detecting and removing sample contamination in phylogenomic data: an example and its implications for Cicadidae phylogeny (Insecta Hemiptera).
Contamination of a genetic sample with DNA from one or more nontarget species is a continuing concern of molecular phylogenetic studies, both Sanger sequencing studies and next-generation sequencing studies. We developed an automated pipeline for identifying and excluding likely cross-contaminated loci based on the detection of bimodal distributions of patristic distances across gene trees. When contamination occurs between samples within a data set, a comparison between a contaminated sample and its contaminant taxon will yield bimodal distributions with one peak close to zero patristic distance. This new method does not rely on a priori knowledge of taxon relatedness nor does it determine the causes(s) of the contamination. Exclusion of putatively contaminated loci from a data set generated for the insect family Cicadidae showed that these sequences were affecting some topological patterns and branch supports, although the effects were sometimes subtle, with some contamination-influenced relationships exhibiting strong bootstrap support. Long tip branches and outlier values for one anchored phylogenomic pipeline statistic (AvgNHomologs) were correlated with the presence of contamination
A molecular phylogeny of the cicadas (Hemiptera: Cicadidae) with a review of tribe and subfamily classification:
A molecular phylogeny and a review of family-group classification are presented for 137 species (ca. 125 genera) of the insect family Cicadidae, the true cicadas, plus two species of hairy cicadas (Tettigarctidae) and two outgroup species from Cercopidae. Five genes, two of them mitochondrial, comprise the 4992 base-pair molecular dataset. Maximum-likelihood and Bayesian phylogenetic results are shown, including analyses to address potential base composition bias. Tettigarcta is confirmed as the sister-clade of the Cicadidae and support is found for three subfamilies identified in an earlier morphological cladistic analysis. A set of paraphyletic deep-level clades formed by African genera are together named as Tettigomyiinae n. stat. Taxonomic reassignments of genera and tribes are made where morphological examination confirms incorrect placements suggested by the molecular tree, and 11 new tribes are defined (Arenopsaltriini n. tribe, Durangonini n. tribe, Katoini n. tribe, Lacetasini n. tribe, Macrotristriini n. tribe, Malagasiini n. tribe, Nelcyndanini n. tribe, Pagiphorini n. tribe, Pictilini n. tribe, Psaltodini n. tribe, and Selymbriini n. tribe). Tribe Tacuini n. syn. is synonymized with Cryptotympanini, and Tryellina n. syn. is synonymized with an expanded Tribe Lamotialnini. Tribe Hyantiini n. syn. is synonymized with Fidicinini. Tribe Sinosenini is transferred to Cicadinae from Cicadettinae, Cicadatrini is moved to Cicadettinae from Cicadinae, and Ydiellini and Tettigomyiini are transferred to Tettigomyiinae n. stat from Cicadettinae. While the subfamily Cicadinae, historically defined by the presence of timbal covers, is weakly supported in the molecular tree, high taxonomic rank is not supported for several earlier clades based on unique morphology associated with sound production
Phylogenomics Reveals Ancient Gene Tree Discordance in the Amphibian Tree of Life
Molecular phylogenies have yielded strong support for many parts of the amphibian Tree of Life, but poor support for the resolution of deeper nodes, including relationships among families and orders. To clarify these relationships, we provide a phylogenomic perspective on amphibian relationships by developing a taxon-specific Anchored Hybrid Enrichment protocol targeting hundreds of conserved exons which are effective across the class. After obtaining data from 220 loci for 286 species (representing 94% of the families and 44% of the genera), we estimate a phylogeny for extant amphibians and identify gene tree–species tree conflict across the deepest branches of the amphibian phylogeny. We perform locus-by-locus genealogical interrogation of alternative topological hypotheses for amphibian monophyly, focusing on interordinal relationships. We find that phylogenetic signal deep in the amphibian phylogeny varies greatly across loci in a manner that is consistent with incomplete lineage sorting in the ancestral lineage of extant amphibians. Our results overwhelmingly support amphibian monophyly and a sister relationship between frogs and salamanders, consistent with the Batrachia hypothesis. Species tree analyses converge on a small set of topological hypotheses for the relationships among extant amphibian families. These results clarify several contentious portions of the amphibian Tree of Life, which in conjunction with a set of vetted fossil calibrations, support a surprisingly younger timescale for crown and ordinal amphibian diversification than previously reported. More broadly, our study provides insight into the sources, magnitudes, and heterogeneity of support across loci in phylogenomic data sets
A global phylogeny of butterflies reveals their evolutionary history, ancestral hosts and biogeographic origins
Butterflies are a diverse and charismatic insect group that are thought to have evolved with plants and dispersed throughout the world in response to key geological events. However, these hypotheses have not been extensively tested because a comprehensive phylogenetic framework and datasets for butterfly larval hosts and global distributions are lacking. We sequenced 391 genes from nearly 2,300 butterfly species, sampled from 90 countries and 28 specimen collections, to reconstruct a new phylogenomic tree of butterflies representing 92% of all genera. Our phylogeny has strong support for nearly all nodes and demonstrates that at least 36 butterfly tribes require reclassification. Divergence time analyses imply an origin similar to 100 million years ago for butterflies and indicate that all but one family were present before the K/Pg extinction event. We aggregated larval host datasets and global distribution records and found that butterflies are likely to have first fed on Fabaceae and originated in what is now the Americas. Soon after the Cretaceous Thermal Maximum, butterflies crossed Beringia and diversified in the Palaeotropics. Our results also reveal that most butterfly species are specialists that feed on only one larval host plant family. However, generalist butterflies that consume two or more plant families usually feed on closely related plants
The plain puffin Appias indra Swinhoe: Behaviour, life-history and distribution
Volume: 95Start Page: 137End Page: 13
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The Wildlife (Protection) Act and Conservation Prioritization of Butterflies of the Western Ghats, Southwestern India
Various schedules of the Wildlife (Protection) Act, 1972 (henceforth WPA), dictate the level of legal protection given to species of Indian animals. Shortcomings of the schedules of the WPA with respect to insects have been pointed out, but no solutions have been suggested. Here I have used butterflies of the Western Ghats as a case study, analysed their conservation values with multiple species attributes and then compared my findings with the species listed under the WPA. Analysis shows that a large proportion of species with high conservation values, many of them narrowly endemic and endangered, are not listed under the WPA, indicating the need to expand the listings. This methodology can be used to objectively assess conservation values of other animals and their inclusion in the WPA.Integrative Biolog
Species Composition, Sex ratios and Movement Patterns in Danaine Butterfly Migrations in Southern India
Volume: 102Start Page: 280End Page: 28
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