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Abstract Dormice (family Gliridae) are an ancient group of rodents. It was fully dominant in the Oligocene and Early Miocene, and its current diversity is represented by a few extant species. A Kazakhstani endemic, the desert dormouse Selevinia betpakdalaensis is one of the most enigmatic dormouse species. Lack of genetic data has not allowed Selevinia to be included in previous molecular phylogenetic analyses. In the current study, we report the first genetic data on S. betpakdalaensis as well as mitochondrial genomes of Myomimus roachi and Glirulus japonicus (retrieved from museum specimens) and a mitogenome of Graphiurus murinus (assembled from SRA data). The assembled mitochondrial genomes were combined with available mitochondrial data from GenBank to reconstruct the mitochondrial phylogeny of Gliridae. Taking into account a distortion of the phylogeny as a result of an analysis of the saturated third codon position, we obtained for the first time a resolved phylogeny of the family. The first split within Gliridae was estimated as an average of 34.6 Mya, whereas divergence time of subfamilies Graphiurinae and Glirinae was assessed at 32.67 Mya. The phylogenetic analysis confirmed the relationship (previously shown based on cranial and mandibular morphology) between Selevinia and the Myomimus.

The extraction of museum DNA from a unique collection of samples of the “Crocidura pergrisea” species complex, which comprises local endemics of Central and West Asia, allowed us to determine their inter- and intragroup relationships. The first step of this study was the re-evaluation of heavily damaged type specimens of C. armenica via a microcomputed-tomography-based cybertaxonomic approach (CTtax), which enabled a precise description of the species’ morphology; three-dimensional models of the cybertypes were made available through the MorphoBank Repository. We developed the “AProMaDesU” pipeline on the basis of five requirements for micro-CT-based cyber-datasets in relation to mammalian collections. Our second step was a combination of several meticulous approaches to morphological investigation against a background of a cytb-based phylogeny, which helped us to make a taxonomic decision about the status of species of the “pergrisea” group, e.g., C. arispa, C. armenica, and C. serezkyensis, when the morphological results were partly incongruent with the molecular phylogeny. Nevertheless, under two assumptions, our findings preserved a separate species-level status of C. serezkyensis and C. arispa. In addition, we restored the species-level status of C. armenica. This taxonomic decision is based on our morphospace analysis, which revealed unique craniomandibular shape transformations within the rocky shrews that helped them with the transition to a new area of morphospace/trophic niches and consequently separated them from the other analyzed Crocidura groups.

Despite the high level of interest, the population history of arctic foxes during the Late Pleistocene and Holocene remains poorly understood. Here we aimed to fill gaps in the demographic and colonization history of the arctic fox by analyzing new ancient DNA data from fossil specimens aged from 50 to 1 thousand years from the Northern and Polar Urals, historic DNA from museum specimens from the Novaya Zemlya Archipelago and the Taymyr Peninsula and supplementing these data by previously published sequences of recent and extinct arctic foxes from other regions. This dataset was used for reconstruction of a time-calibrated phylogeny and a temporal haplotype network covering four time intervals: Late Pleistocene (ranging from 30 to 13 thousand years bp), Holocene (ranging from 4 to 1 thousand years bp), historical (approximately 150 years), and modern. Our results revealed that Late Pleistocene specimens showed no genetic similarity to either modern or historical specimens, thus supporting the earlier hypothesis on local extinction rather than habitat tracking.