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Integrative taxonomy seeks to approach the complex topic of species diagnosis using independent, complementary lines of evidence. Despite their ubiquity throughout North and Central America, taxonomy of the American leopard frogs (Anura: Ranidae: Rana: subgenus Pantherana) remains largely unresolved, and this is arguably nowhere truer than in the Central American country of Honduras, where there are two nominal species, the taxonomy of which remains unresolved. Leopard frogs from several mountainous areas along the continental divide in Honduras have previously been considered putative hybrids between Rana brownorum and R. cf. forreri, as opposed to two alternate hypotheses: one that they represent a high-altitude eco-morph of a single widespread species that included both lowland forms, or a second that there is an undescribed highland species distinct from either of the recognized lowland forms. We examine this set of hypotheses using three independent lines of evidence. First, we used species distribution modelling to examine potential geographic isolation of the highland form and the two putative parental lowland species, and found strong ecological separation between the highland and lowland forms. Second, mitochondrial and nuclear DNA supports the distinction of the highland form from both putative parental species, with mtDNA data refuting the hypothesis that representatives of either species may represent a matrilineal founder. Morphologically, the highland form is significantly smaller than, and otherwise readily differentiated from, both R. brownorum and R. cf. forreri, as well as all other Rana found in Honduras and adjacent areas. As a result, we formally describe the highland leopard frog as a new species. http://zoobank.org/urn:lsid:zoobank.org:pub:BE53F587-3618-4433-9651-E495808E5474 [ABSTRACT FROM AUTHOR]

The mid-Holocene has had profound demographic impacts on wildlife on the African continent, although there is little known about the impacts on species from Central Africa. Understanding the impacts of climate change on codistributed species can enhance our understanding of ecosystem dynamics and for formulating restoration objectives. We took a multigenome comparative approach to examine the phylogeographic structure of two poorly known Central African crocodile species- Mecistops sp. aff. cataphractus and Osteolaemus tetraspis. In addition, we conducted coalescent-based demographic reconstructions to test the hypothesis that population decline was driven by climate change since the Last Glacial Maximum, vs. more recent anthropogenic pressures. Using a hierarchical Bayesian model to reconstruct demographic history, we show that both species had dramatic declines (>97%) in effective population size in the 'period following the Last Glacial Maximum 1,500-18,000 YBP. Identification of genetic structuring showed both species have similar regional structure corresponding to major geological features (i.e., hydrologic basin) and that small observed differences between them are best explained by the differences in their ecology and the likely impact that climate change had on their habitat needs. Our results support our hypothesis that climatic effects, presumably on forest and wetland habitat, had a congruent negative impact on both species. [ABSTRACT FROM AUTHOR]

Imperiled Okaloosa darters ( Etheostoma okaloosae) are small, benthic fish limited to six streams that flow into three bayous of Choctawhatchee Bay in northwest Florida, USA. We analyzed the complete mitochondrial cytochrome b gene and 10 nuclear microsatellite loci for 255 and 273 Okaloosa darters, respectively. Bayesian clustering analyses and AMOVA reflect congruent population genetic structure in both mitochondrial and microsatellite DNA. This structure reveals historical isolation of Okaloosa darter streams nested within bayous. Most of the six streams appear to have exchanged migrants though they remain genetically distinct. The U.S. Fish and Wildlife Service recently reclassified Okaloosa darters from endangered to threatened status. Our genetic data support the reclassification of Okaloosa darter Evolutionary Significant Units (ESUs) in the larger Tom's, Turkey, and Rocky creeks from endangered to threatened status. However, the three smaller drainages (Mill, Swift, and Turkey Bolton creeks) remain at risk due to their small population sizes and anthropogenic pressures on remaining habitat. Natural resource managers now have the evolutionary information to guide recovery actions within and among drainages throughout the range of the Okaloosa darter. [ABSTRACT FROM AUTHOR]

Abstract: We compare patterns of lineage divergence in mitochondrial DNA (mtDNA) sequences of two protein-encoding mitochondrial genes (cyt b and ND2) in two ecologically similar, co-distributed, and closely related ranid frogs (Rana clamitans and Rana catesbeiana), that are geographically widespread, and frequently syntopic. We identified three lineages in R. clamitans, separated by 0.5% to 2.1% net corrected sequence divergence, comparable to two R. catesbeiana lineages separated by 0.6%. The geographic pattern of lineage distribution differed notably between the two species. In R. clamitans, we found a Coastal Plain-Appalachian (CPA) lineage restricted to south and east of the Appalachian Mountains and a widespread lineage that encompassing nearly all the sampled range. A third distinct and divergent lineage was detected in one location in the southwest portion of the range (Louisiana). This pattern contrasts with the east-west pattern in R. catesbeiana, and reflects possible differences in refugial dynamics and patterns of range expansion. Although both species have undergone range expansion and population growth, coalescent reconstruction of N e reflects larger lineages but more recent divergence in R. clamitans relative to R. catesbeiana, reflecting significant differences in population history or divergent patterns of molecular evolution at mtDNA. [Copyright &y& Elsevier]

Existing taxonomic studies of Reticulitermes spp. (Isoptera: Rhinotermitidae) from California provide information on only two described species: Reticulitermes hesperus Banks and Reticulitermes tibialis Banks. However, while conducting a genetic evaluation of the genus from North America, we find evidence of species that cannot be identified morphologically with existing information. We also update more current information about other species detected during our investigations, including the positive identification of R. flavipes from California. Therefore, we have conducted a molecular genetics study involving DNA sequencing of a portion of the mitochondrial DNA (mtDNA) 16S gene to determine the extent of genetic variation within Reticulitermes from California. We analyzed 94 samples. Twenty-five nucleotide sites were variable in R. hesperus, and 19 mtDNA haplotypes were observed in the 428-bp mtDNA sequence. Fourteen haplotypes (37%) occurred only once, whereas the most common haplotypes, HE4 and HE9, each occurred in 18% of the samples. Although some haplotypes were found to have a broad geographical range across the state, some were restricted to the southern region, as were all samples identified as R. tibialis. Twelve haplotypes of an undescribed western species, R. n. sp. 'R. okanaganensis,' were found, and its distribution throughout the state is discussed. Additionally, genetic evidence of two additional undescribed Reticulitermes species from southern California is presented. [ABSTRACT FROM AUTHOR]

A molecular genetics study involving DNA sequencing of a portion of the mitochondrial DNA 16S gene was undertaken to determine the extent of genetic variation within Reticulitermes flavipes (Kollar) in North America. This study was done because differences in morphological variants (of R. flavipes) would presumably translate into genetic differences, and there are no prior studies that describe its genetic variation from the extent of its North American range. In total, 493 samples were analyzed from the United States, Canada, and Mexico. Nineteen nucleotide sites were variable in the 428-bp mitochondrial DNA (mtDNA) sequence, and 47 mtDNA haplotypes were observed. Nine haplotypes (19%) occurred only once, whereas the most common haplotype, F, occurred in 17% of the samples. Four haplotypes were found over a broad geographical range encompassing at least nine states each. The single haplotype found in Toronto, Canada, also occurs in Arkansas, whereas two of the three haplotypes found in Mexico are unique to that country. Based on this research, there seems to be numerous R. flavipes haplotypes that are widespread, perhaps due to human involvement. whereas other haplotypes may be more rare and could represent locally adapted populations. [ABSTRACT FROM AUTHOR]

Morphological examination of soldiers and imagos assigned to Nasutitermes corniger or N. costalis from 13 Neotropical countries and 42 West Indian islands revealed congruent characters and biometric overlap. A portion of the mitochondrial DNA 16S rRNA gene was sequenced from nine N. costalis and N. corniger samples. Molecular phylogenetic analysis of the N. costalis/corniger DNA sequences relative to other Nasutitermes spp. supported the morphological evidence that these species are conspecific. Complementary biological, behavioral, biochemical, and reproductive ecology further support the presented synonymy. The senior synonym, N. corniger, is given nomenclatural precedence. The geographical distribution of N. corniger is revised. [ABSTRACT FROM AUTHOR]

The Holoarctic termite genus Reticulitermes is widely distributed in Europe. A new Reticulitermes species, R. sp. nov, was recently found in France and Italy. Its phylogenetic position was investigated using a 743-bp fragment of mitochondrial 16S rRNA-ND1 genes and 382-bp of the nuclear ITS2 region. Phylogenies for these sequences were estimated by neighbor-joining, maximum-parsimony and maximum-likelihood analysis. The results strongly supported a relationship between R. sp. nov. and the termite species from the eastern Mediterranean area including Reticulitermes balkanensis from the Balkans, Reticulitermes lucifugus from Turkey and Reticulitermes clypeatus from Israel. The hypothesis of a relationship between R. sp. nov. and the Japanese Reticulitermes speratus was rejected by parametric bootstrap. The current distribution of R. sp. nov. could be linked to postglacial colonization routes between Balkan refuge and northern regions. [Copyright &y& Elsevier]

The article presents a study on a new species of cloud forest salamander in the Bolitoglossa dunni group (Plethodontidae: Caudata: Bolitoglossinae) from Parque Nacional Montaña de Yoro, Honduras. It says that the new species is different from other species in the group base on molecular and morphological characteristics. It mentions that the mitochondrial DNA sequence of the new species is most likely linked to a species endemic to cloud forest B. decora. Moreover, the discovery of A. morazani and Bolitoglossa cataguana during fieldwork should be regarded as an indicator of undocumented endemism within the reserve, as well as other taxonomic group.