Evolutionary history and population genetic structure of the endemic tree frogHyla tsinlingensis(Amphibia: Anura: Hylidae) inferred from mitochondrial gene analysis

Genetic structure and demographic history of Indirana semipalmata, an endemic frog species of the Western Ghats, India

The evolutionary potential of a species mainly depends on the level of genetic variation in their populations. Maintenance of gene variation enables populations to adapt more quickly to environmental changes. The geographical gaps also influence the distribution and evolutionary history of many mountain frogs in the world. Hence, a sound knowledge in population genetic structure of a species will help understand its population dynamics and develop conservation strategies. In the context of facing threats to the amphibian fauna of Western Ghats due to habitat loss, we used both mitochondrial and nuclear DNA markers to investigate the genetic structure of an endemic frog species of the Western Ghats (Indirana semipalmata) with restricted distribution. The present study showed the importance of mountain gaps in shaping the species' structuring in the Western Ghats. Though a high genetic diversity was observed for the species when considering a single unit in the southern Western Ghats, the restricted gene flow on/between either side of the Shencottah gap with genetic clustering of the sampled populations may warrant a unique management plan for the species. The habitat fragmentation of the Western Ghats through anthropogenic activities may result in severe setbacks to the survival of the species in the future.

One step beyond a broad molecular phylogenetic analysis: Species delimitation of Adenomera marmorata Steindachner, 1867 (Anura: Leptodactylidae)

Taxonomists always have had intense discussions about how species should be delimited and recently many studies have used integrative approaches by combining molecular, morphological, and bioacoustic data. Although these studies are paramount for understanding species diversity, few of them actually formalize species delimitations to the final step of nomenclatural acts. Historically, the Neotropical frog genus Adenomera has been considered as a difficult taxonomic group because it comprises many morphologically similar species exhibiting high levels of intraspecific polymorphism. A recent work using molecular data shed light on the phylogenetic relationships within the genus and identified several lineages that may correspond to undescribed species but did not delimit species boundaries. In the Atlantic Forest, a clade formed by A. marmorata and two putative species (Adenomera sp. J and Adenomera sp. K) were identified. In this paper, we combine morphological, acoustic, and molecular data in order to evaluate species limits within this Atlantic Forest Adenomera clade. We provide a redescription of A. marmorata and restrict its type locality to the Tijuca Massif, in the Municipality of Rio de Janeiro, Brazil. Our results do not support A. marmorata and the two candidate species as diagnosable distinct species. Therefore A. marmorata corresponds to a species with pronounced morphological and acoustic variation in the genus and a complex phylogeographic structure.

Yangtze River, an insignificant genetic boundary in tufted deer (Elaphodus cephalophus): the evidence from a first population genetics study

Great rivers were generally looked at as the geographical barrier to gene flow for many taxonomic groups. The Yangtze River is the third largest river in the world, and flows across South China and into the East China Sea. Up until now, few studies have been carried out to evaluate its effect as a geographical barrier. In this study, we attempted to determine the barrier effect of the Yangtze River on the tufted deer (Elaphodus cephalophus) using the molecular ecology approach. Using mitochondrial DNA control region (CR) sequences and 13 nuclear microsatellite loci, we explored the genetic structure and gene flow in two adjacent tufted deer populations (Dabashan and Wulingshan populations), which are separated by the Yangtze River. Results indicated that there are high genetic diversity levels in the two populations, but no distinguishable haplotype group or potential genetic cluster was detected which corresponded to specific geographical population. At the same time, high gene flow was observed between Wulingshan and Dabashan populations. The tufted deer populations experienced population decrease from 0.3 to 0.09 Ma BP, then followed by a distinct population increase. A strong signal of recent population decline (T = 4,396 years) was detected in the Wulingshan population by a Markov-Switching Vector Autoregressions(MSVAR) process population demography analysis. The results indicated that the Yangtze River may not act as an effective barrier to gene flow in the tufted deer. Finally, we surmised that the population demography of the tufted deer was likely affected by Pleistocene climate fluctuations and ancient human activities.

Sequencing of complete mitochondrial genome for Tsinling Tree Toad (Hyla tsinlingensis)

The complete mitochondrial genome sequence of Hyla tsinlingensis was determined in this research. The length of mitogenome is 17850 bp, including 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, 1 O_L and 1 control region. The phylogentic tree was reconstructed using the BI method based on concatenated nucleotide sequences of mtDNA genes (12S ribosomal small subunit gene/12S rRNA; NADH dehydrogenase subunit 1 gene/ND1, including adjacent transfer RNAs and the partial 16S ribosomal large subunit gene). The phylogenetic tree was split into two clades, Clade A and Clade B. The H. tsinlingensis which we determined clustered into Clade A.