Phylogeny, taxonomic reassessment and ‘ecomorph’ relationship of theOrientallactaga sibiricacomplex (Rodentia: Dipodidae: Allactaginae)

Abstract

The ecological gradient–morphological variation (‘ecomorph’) relationship has long interested ecologists and evolutionary biologists, but it is applied far less frequently than genetic differentiation in cryptic species detection and species identification. With integrative methods, we revise taxonomic uncertainties in the Orientallactaga sibirica complex (OSC), with 298 sequence specimens and 469 voucher specimens from 138 localities covering nearly the entire distribution of the OSC. Phylogenetic relationships are assessed by Bayesian inference and maximum likelihood using two mitochondrial and nine nuclear genes. We use species-delimitation approaches to divide and validate the ‘candidate species’. We evaluate correlations between ecological divergence and phylogenetic splits, and visualize geographical patterns of morphological variation. The OSC is divided into four phylogenetic groups, the Ognevi, Altay, Bogda and Sibirica groups, and the OSC exhibits a significant ecomorph relationship and ecological divergence pattern. Morphological variations not only follow the general regularity under a large gradient of ecological factors, but are also closely related to the local environment/habitat. We suggest considering the comprehensive ecomorph relationship to identify species. Molecular analyses reveal that the OSC more easily forms deeply divergent lineages in the foothills and this differentiation depth may be related to mountain system size.

Phylogenetic relations and range history of jerboas of the Allactaginae subfamily (Dipodidae, Rodentia)

“…The crown age of O. sibirica was estimated at 500–600 kya, which was substantially younger than 2.2–3.2 Mya as inferred by Cheng et al 23 ; this discrepancy, however, can be explained by mtDNA saturation effects and usage of inaccurate secondary calibrations in their study.…”

“…The mtDNA data tentatively supported subdivision of O. sibirica into western and eastern groups separated by the Tianshan–Altay zoogeographic boundary. The structure of variation in the eastern portion of the range (Mongolia, China) is well-studied 23 ; however, the genetic data on the western portion are still fragmentary. Available mtDNA data provisionally support recognition of western subspecies such as O. s. ognevi (north-eastern to central Kazakhstan), O. s. dementjevi (Issyk-Kul region), and O. s. altorum (central Tianshan).…”

“…Pygeretmus ) appeared controversial. Other studies focused on particular species groups demonstrating substantial cryptic diversity and found that some species are in fact complex species groups containing new species 18 – 23 . These findings require confirmation based on further genetic data and broader taxon sampling.…”

Distribution patterns and drivers of nonendemic and endemic glires species in China

“…We compiled a database of glires species distribution based on the latest mammal list (Wei et al, 2021). Species distribution data were obtained from the following sources: (1) the research results of Zhou (2000) and Xing (2008); (2) National Zoological Museum of China, NZMC; (3) Global Biodiversity Information Facility (GBIF); and (4) distribution and collection records available in books or literature (Cheng et al, 2021; Ge et al, 2018; Jackson et al, 2022; Jiang et al, 2015; Li et al, 2019; Liu et al, 2019, 2020). All Chinese lands were used as study areas in this study, and species distribution data from outside China were excluded to ensure the successful operation of the model (Wang et al, 2021).…”

Distribution patterns and drivers of non-endemic and endemic rodent species in China

“…We compiled a database of rodent species distribution in China. Species distribution data were obtained mainly from the following sources: 1) the research results of Zhou et al (2002) and Xing et al (2008); 2) National Zoological Museum of China, NZMC; 3) Global Biodiversity Information Facility (GBIF); and 4) distribution and collection records available in books or literature (Jiang et al, 2015;Ge et al, 2018;Cheng et al, 2021;Jackson et al, 2022). After removing null values, offset values, and redundant data from the distribution records, 237 species of rodents in two orders were included in the analysis of this study.…”