Discovery of a new mammal species (Soricidae: Eulipotyphla) from Narcondam volcanic island, India

We discovered a new Crocidura species of shrew (Soricidae: Eulipotyphla) from Narcondam Island, India by using both morphological and molecular approaches. The new species, Crocidura narcondamica sp. nov. is of medium size (head and body lengths) and has a distinct external morphology (darker grey dense fur with a thick, darker tail) and craniodental characters (braincase is rounded and elevated with weak lambdoidal ridges) in comparison to other close congeners. This is the first discovery of a shrew from this volcanic island and increases the total number of Crocidura species catalogued in the Indian checklist of mammals to 12. The newly discovered species shows substantial genetic distances (12.02% to 16.61%) to other Crocidura species known from the Indian mainland, the Andaman and Nicobar Archipelago, Myanmar, and from Sumatra. Both Maximum-Likelihood and Bayesian phylogenetic inferences, based on mitochondrial (cytochrome b) gene sequences showed distinct clustering of all included soricid species and exhibit congruence with the previous evolutionary hypothesis on this mammalian group. The present phylogenetic analyses also furnished the evolutionary placement of the newly discovered species within the genus Crocidura.

Phylogeography of a Darevskia (caucasica) complex (Lacertidae: Sauria) based on the cytochrome b mitochondrial gene analysis

The range of superspecific complex of rock lizards Darevskia (caucasica) (D. alpina, D. c. caucasica, D. c. vedenica, D. daghestanica) includes the Main Caucasian ridge and its spurs on the southern and northern macroslopes within heights from 500 m to 3200 m above sea level. A fragment of the mitochondrial cytochrome b gene (1096 bp) was analyzed in 48 specimens of these lizards. Specimens were collected in 23 localities. We have found 39 unique haplotypes. The minimum genetic diversity was found in D. c. vedenica, maximum in D. c. caucasica. All taxa of the complex, except for D. c. vedenica, demonstrate genetic heterogeneity. Four clades can be distinguished on the dendrogram of phylogenetic relationships. They correspond to D. alpina, D. c. caucasica, D. c. vedenica, D. daghestanica. D. c. caucasica forms two distinct haplogroups. On the phylogenetic tree, the sample of D. c. vedenica formed an independent clade close to D. c. caucasica. The Darevskia (caucasica) complex is polyphyletic according to the analysis of the mitochondrial marker. Nucleotide sequences of D. alpina formed a single clade with Darevskia (saxicola) complex representatives and combined with the sequences of D. brauneri into subclade. On the example of the population of D. daghestanica, found in a forest biotope without rocky outcrops and genetically not differing from individuals from the adjacent territory, the ability of rocky lizards to master biotopes unusual for them in a short period of time was demonstrated. This example demonstrates the ability of rock lizards to adapt to unusual biotopes in a short period of time. Genetic distance between D. c. vedenica and D. c. caucasica is comparable to the distance between D. c. caucasica and D. daghestanica. We assume the existence of an independent form of D. caucasica ssp. inhabiting South Ossetia and adjacent territories.

Genetic differentiation of geographic populations of Rattus tanezumi based on the mitochondrial Cytb gene

Rattus tanezumi is a common domestic rat and host of the bubonic plague pathogen in China and Southeast Asia (SEA). The origin, genetic differentiation and dispersal of R. tanezumi have received increasing attention from researchers. The population genetics of R. tanezumi based on its mitochondrial cytochrome b gene have been studied to explain the origin, relationships and dispersal of populations. In this study, we captured a total of 229 rats; morphological and molecular biological identification cytochrome oxidase subunit I (COI) confirmed 131 R. tanezumi individuals collected from 6 provincial areas, and their Cytb gene sequences were analyzed. The results showed that the population in Mohan (MH), Yunnan, had the highest genetic diversity, while that in Ningde (ND), Fujian, had the lowest. Tajima’s D statistic for all populations was negative and nonsignificant, indicating the possible expansion of R. tanezumi populations. Low gene flow occurred between the Zhangmu (ZM) R. tanezumi population and other populations, and the genetic differentiation among them was high. Furthermore, our analyses revealed the ZM lineage was the oldest lineage among the groups and diverged ~1.06 Mya, followed by the Luoyang (LY) lineages (~0.51 Mya) and Yunnan lineage (~0.33 Mya). In southeastern Yunnan, the Jinshuihe (JSH) and MH populations were more closely related to the populations in southeastern China (Fuzhou (FZ), ND, Quanzhou (QZ), Nanchang (NC)) and inland areas (Chongqing (CQ), LY) than to those in other areas of Yunnan (Jiegao (JG) and Qingshuihe (QSH)), indicating that R. tanezumi may have spread from southeastern Yunnan to the interior of China. In summary, R. tanezumi may have originated in ZM and adjacent areas, spread to Yunnan, and then spread from the southeast of Yunnan inland or directly eastward from ZM to inland China.

Phylogenetic relationships among Callosciurus squirrels in the Indochina Peninsula: phylogenetic position of C. pygerythrus from Myanmar

The phylogenetic relationships among seven Callosciurus species from the Indochina Peninsula, including the C. honkhoaiensis which is endemic to Hon Khoai Island, were studied using complete mitochondrial cytochrome b gene sequences (1140 bases). We primarily focused on the phylogenetic position of C. pygerythrus, which is distributed in the western part of the peninsula. We identified two main lineages: 1) C. caniceps, C. honkhoaiensis, C. inornatus, C. phayrei and C. pygerythrus, and 2) C. erythraeus and C. finlaysonii. Estimated divergence time between the two lineages was at the junction of the Zanclean and Piacenzian in the Pliocene. Within the first linage, the divergence time of sub-lineages corresponded to the Pliocene-Pleistocene boundary, although phylogenetic relationships were unclear. These two divergence times estimated in the present study correspond to episodes of global cooling, suggesting that climate may have contributed to the divergence of these Callosciurus squirrels.

On the taxonomy and systematics of the recently described Lycodon deccanensis Ganesh, Deuti, Punith, Achyuthan, Mallik, Adhikari, Vogel, 2020 (Serpentes, Colubridae) from India

Lycodon deccanensis Ganesh, Deuti, Punith, Achyuthan, Mallik, Adhikari, Vogel, 2020 was recently described from the Mysore plateau of Karnataka based solely on morphology but lacking in-depth descriptions and comparisons. A scrutiny of the description reveals that the type series, of two specimens, comprise specimens of two different species along with discrepancies throughout the paper. Surveys conducted near the type locality of the species led to the discovery of additional specimens, which allow us to provide an elaborate description of the species and present data on its phylogenetic relationship with members of the genus and comments on the systematics of Lycodon of India. Results from molecular phylogenetics suggest that Lycodon deccanensis is a member of the L. aulicus clade based on molecular data for mitochondrial cytochrome b gene and shows an un-corrected p-distance (sequence divergence) of 14–17% from other members of the Lycodon aulicus clade.