Sorex Minutissimus Research Articles

Fossil insectivorous mammals (Eulipotyphla) of the southern Pre-Urals (Bashkortostan, Russia)

Seven species of red-toothed shrews (Sorex araneus, Sorex isodon, Sorex tundrensis, Sorex caecutiens, Sorex minutus, Sorex minutissimus, Neomys fodiens), white-toothed shrews (Crocidura sp.), moles (Talpa sp.) and hedgehogs (Erinaceus sp.) were found in Late Pleistocene and Holocene deposits of the southern part of the western slope of the Ural Mountains. In the Late Pleistocene and Early Holocene deposits, the red-toothed shrews were dominated by S. tundrensis. This species disappeared from the area by the Late Holocene, when S. araneus became the predominant species. Smaller mandibular sizes have been registered for S. araneus in the Middle and Late Holocene, as compared to the sizes of older samples. The morphometric criteria have been established for a species differential diagnosis of the Late Pleistocene – Early Holocene mandibular samples of S. araneus and S. tundrensis, found in local deposits of the southern Pre-Urals area studied.

Geographic Distribution and Phylogeny of Soricine Shrew-Borne Seewis Virus and Altai Virus in Russia.

The discovery of genetically distinct hantaviruses (family Hantaviridae) in multiple species of shrews, moles and bats has revealed a complex evolutionary history involving cross-species transmission. Seewis virus (SWSV) is widely distributed throughout the geographic ranges of its soricid hosts, including the Eurasian common shrew (Sorex araneus), tundra shrew (Sorex tundrensis) and Siberian large-toothed shrew (Sorex daphaenodon), suggesting host sharing. In addition, genetic variants of SWSV, previously named Artybash virus (ARTV) and Amga virus, have been detected in the Laxmann’s shrew (Sorex caecutiens). Here, we describe the geographic distribution and phylogeny of SWSV and Altai virus (ALTV) in Asian Russia. The complete genomic sequence analysis showed that ALTV, also harbored by the Eurasian common shrew, is a new hantavirus species, distantly related to SWSV. Moreover, Lena River virus (LENV) appears to be a distinct hantavirus species, harbored by Laxmann’s shrews and flat-skulled shrews (Sorex roboratus) in Eastern Siberia and far-eastern Russia. Another ALTV-related virus, which is more closely related to Camp Ripley virus from the United States, has been identified in the Eurasian least shrew (Sorex minutissimus) from far-eastern Russia. Two highly divergent viruses, ALTV and SWSV co-circulate among common shrews in Western Siberia, while LENV and the ARTV variant of SWSV co-circulate among Laxmann’s shrews in Eastern Siberia and far-eastern Russia. ALTV and ALTV-related viruses appear to belong to the Mobatvirus genus, while SWSV is a member of the Orthohantavirus genus. These findings suggest that ALTV and ALTV-related hantaviruses might have emerged from ancient cross-species transmission with subsequent diversification within Sorex shrews in Eurasia.

The complete mitochondrial genome of Sorex minutissimus (Eulipotyphla: Soricidae)

In this study, the complete mitochondrial genome of Sorex minutissimus was sequenced and deposited to GeneBank for the first time using muscle tissue. This mitochondrial genome is a circular molecule of 16,700 bp in length and sequence analysis showed it contains 2 rRNA genes, 22 tRNA genes, 13 protein-coding genes, rep_origin, and D_loop. Phylogenetic analysis on the basis of 12 protein-coding genes except ND6 of 13 Soricidae species’ mitochondrial genomes using ML and BI demonstrated that S. minutissimus and other Sorex species were clustered into same clade.

Первые сведения о фауне и населении грызунов (Rodentia) и насекомоядных (Eulipotyphla) Хингано-Архаринского заказника

This is the first data on the fauna and biotopical distribution of rodents and insectivores of the Khingano-Arkharinskyi zakaznik. The preliminary results are based on field research led in 2011, 2012, 2015 and 2017. Five species of shrews (Sorex caecutiens, S. daphaenodon, S. tundrensis, S. isodon, S. roboratus) and nine species of rodents (Sciurus vulgaris, Tamias sibiricus, Craseomys rufocanus, Myodes rutilus, Alexandromys maximowiczii, Micromys minutus, Apodemus peninsulae, A. agrarius, Sicista caudata) were reliably detected, including the first find of S. caudata in Amurskaya Oblast (this is the most northwestern point of the range, 190 km to west-northwest from the previously known place). A track on snow has been found that was possibly left by Neomys fodiens. The possibility of residence of other species is discussed according to their ranges analysis and presence in Khinganskyi Nature Reserve situated 40 km to the south. The whole Middle Amur region is a territory with a complex landscape structure with intermixture of boreal, nemoral and steppe biotic components and the corresponding «transitional» character of the fauna. Many species have range borders here. Two steppe species (Cricetulus barabensis, Urocitellus undulatus) living in Khinganskyi Reserve or on adjacent territories cannot be found in the zakaznik. Two nemoral species (Erinaceus amurensis and Сrocidura lasiura, rare in Khinganskyi Reserve) have their northern range borders near the southern border of the zakaznik, they are likely to be absent here due to lack of needed habitats. The zakaznik is situated on the northern periphery of Alexandromys fortis range and the western periphery of Sorex gracillimus range, further field research is needed to clarify their status here. Two more species (Sorex minutissimus, Pteromys volans) have not been found yet but they obviously live on this territory.

Highly Divergent Genetic Variants of Soricid-Borne Altai Virus (Hantaviridae) in Eurasia Suggest Ancient Host-Switching Events.

With the recent discovery of genetically distinct hantaviruses (family Hantaviridae) in shrews (order Eulipotyphla, family Soricidae), the once-conventional view that rodents (order Rodentia) served as the primordial reservoir hosts now appears improbable. The newly identified soricid-borne hantaviruses generally demonstrate well-resolved lineages organized according to host taxa and geographic origin. However, beginning in 2007, we detected sequences that did not conform to the prototypic hantaviruses associated with their soricid host species and/or geographic locations. That is, Eurasian common shrews (Sorex araneus), captured in Hungary and Russia, were found to harbor hantaviruses belonging to two separate and highly divergent lineages. We have since accumulated additional examples of these highly distinctive hantavirus sequences in the Laxmann’s shrew (Sorex caecutiens), flat-skulled shrew (Sorex roboratus) and Eurasian least shrew (Sorex minutissimus), captured at the same time and in the same location in the Sakha Republic in Far Eastern Russia. Pair-wise alignment and phylogenetic analysis of partial and full-length S-, M- and/or L-segment sequences indicate that a distinct hantavirus species related to Altai virus (ALTV), first reported in a Eurasian common shrew from Western Siberia, was being maintained in these closely related syntopic soricine shrew species. These findings suggest that genetic variants of ALTV might have resulted from ancient host-switching events with subsequent diversification within the Soricini tribe in Eurasia.

Shrew dentition (Lipotyphla: Soricidae)—endodontic morphology and its phylogenetic resolving power

Soricid (Lipotyphla: Soricidae) inner tooth structures have been described for the first time using high-resolution X-ray computed micro-tomography. The endodontic morphology of shrews is complex and according to our results can be used (i) for the description of additional odontological features, (ii) for phylogenetic investigations on a morphological basis, and (iii) for determining the homology of the tooth elements. The results of the original analysis revealed a gradual process of dentine formation and, correspondingly, decreasing pulp volume in immature and mature specimens of Sorex mirabilis. However, analysis of the age-related changes also revealed an irregularity in the dentine deposition within different parts of a pulp cavity. We named this irregularity “selective pulp overgrowth”. This process was confirmed by the analyses of specimens of Sorex minutissimus, Neomys fodiens and Blarina brevicauda. Attempts to explain selective overgrowth led us to consider the functions of tooth pulp. According to dentistry investigations, one of the several functions of pulp is dentine innervation. We assume that dentine innervation is a significant feature of soricid teeth. A list of twelve characters displays the possible application of pulp endocast morphology to phylogenetic investigations. We suggest that pulp endocast analysis be added to the analysis of the tooth surface to achieve the broadest and most productive use of tooth morphology.

Sequencing and analysis of the complete mitochondrial genome of the Eurasian least shrew (Sorex minutissimus) from China

The complete mitogenome sequence of the Eurasian least shrew (Sorex minutissimus) was determined using long PCR. The genome was 17,061 bp in length and contained 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes, 1 origin of L strand replication and 1 control region. The overall base composition of the heavy strand is A (32.6%), C (24.7%), T (29.1%) and G (13.6%). The base compositions present clearly the A–T skew, which is most obviously in the control region and protein-coding genes. The extended termination-associated sequence domain, the central conserved domain and the conserved sequence block domain are defined in the mitochondrial genome control region of the Eurasian least shrew. Mitochondrial genome analyses based on MP, ML, NJ and Bayesian analyses yielded identical phylogenetic trees. The ten Sorex species formed a monophyletic group with the high bootstrap value (100%) in all examinations.

First record of the Holarctic least shrew (Sorex minutissimus) and associated helminths from Canada: new light on northern Pleistocene refugia

We report the first Canadian record of the Holarctic least shrew (Sorex minutissimus Zimmermann, 1780) and associated helminth worms, collected along the Dempster Highway in central Yukon in 2014. We identify the specimen based on morphological characters, characterize the habitat, report other mammals and helminth species associated with this specimen, and use mitochondrial DNA sequences to place the specimen within a phylogenetic context and address Pleistocene refugial hypotheses. Although long considered an Eurasian endemic, the diminutive least shrew was first reported from Alaska in 1994. Our new record for Canada indicates that the species may occur at least as far east as the MacKenzie River and DNA variation suggests this species persisted only in the Beringian refugium in North America during the Last Glacial Maximum. The discovery of a new mammal and associated parasites for Canada points to the urgent need for more detailed information on high-latitude biotas in North America, data that are best obtained through museum-based field surveys, particularly for small, cryptic species.

Insectivorous mammals (Lipotyphla, Soricidae) of the Perm Pre-Ural in the Late Pleistocene and Holocene time

Remains of 8 species (Soricidae: Sorex minutissimus, S. minutus, S. caecutiens, S. tundrensis, S. isodon, S. araneus, Neomys sp., Crocidura cf. leucodon) have been found in Late Pleistocene and Holocene layers from 9 localities of the Perm Pre-Ural. Their description, systematic position, and temporal distribution are given. S. tundrensis dominated in the explored territory until the early Holocene. Currently, this species is very rare. Fossil white-toothed shrew (Crocidura cf. leucodon) has been discovered for the first time in the study area.

Analysis of the morphometrics variability and intraspecific structure of Sorex minutissimus Zimmermann, 1780 (Lipotyphla: Soricidae) in Russia

The morphometric relationships among 20 geographical samples of Sorex minutissimus from the Russian part of species range were examined using geometric morphometrics and linear measurements of skull and mandible. Previous studies showed significant differences between immature and mature shrews, and no significant differences between immature males and females. In this paper we propose a method for combining small-sized samples and algorithms for checking the adequacy of such an association. We have identified two main geographical groups of shrews, “Western” and “Eastern”, distinguished by the shape of the mandible; these groups combine samples from the European (S. m. minutissimus) and East-Eurasian (S. m. barabensis, S. m. abnormis, S. m. caudata, S. m. tschuktschorum and S. m. ussurensis) parts of the range. The agreement of our results with phylogeographic data allows us to distinguish two approaches to determining the amount of intraspecific units – “phylogeographic” and “environmental”. On the basis of “environmental” approach within the Russian range we propose to consider seven subspecies: S. m. minutissimus, S. m. barabensis, S. m. stroganovi, S. m. caudata, S. m. tschuktschorum, S. m. ussurensis and S. m. tscherskii.

Intraspecific Phylogeny and Nucleotide Diversity of the Least Shrews, theSorex minutissimus-S. yukonicusComplex, Based on Nucleotide Sequences of the Mitochondrial CytochromebGene and the Control Region

Phylogenetic analysis was conducted for various populations of the Sorex minutissimus-S. yukonicus complex based on mitochondrial gene (cytochrome b and/or the control region) sequences. Sorex minutissimus was divided into some monophyletic groups in Eurasia; it was divided into 2 main groups, eastern and western Eurasian clades, based on combined data of the cytochrome b and the control region. Monophyly of shrews from Hokkaido-Sakhalin, Primorye, Mongolia-Transbaikalia, southeastern Finland was strongly supported respectively in most analyses. Sorex yukonicus was phylogenetically close to S. minutissimus in eastern Siberia. Some shrews from western and central Siberia were included in the clade of southeastern Finland. Also, most shrews from central-northern Finland and Norway made a clade close to but different from the southeastern Finland clade. This finding suggests that Fennoscandian shrews might consist of individuals which were recolonised from various refugia after the Last Glacial Maximum. Nucleotide diversity of shrews from Hokkaido and Alaska was low. Three regional groups in Kamchatka-Sakha, Sakhalin, and Mongolia-Transbaikalia tended to have medium nucleotide diversity. In contrast, shrews from Cisbaikalia-western Siberia and Fennoscandia had high nucleotide diversity. The S. minutissimus-S. hosonoi group appears to have experienceed a quit different biogeographic history from two shrews with similar ranges, the S. caecutiens-S. hosonoi group and S. tundrensis.

Sorex fossils (Soricidae, Insectivora) from the Middle Pleistocene cave site of Shanyangzhai, Hebei Province, China

This paper reports the Sorex fossils found in the Middle Pleistocene Shanyangzhai cave sediments in Qinhuangdao city of North China. The red shrew fossils include Sorex araneus, Sorex minutus, Sorex minutissimus and Sorex cf. mirabilis. S. minutus is reported for the first time in Middle Pleistocene sediments in China. It is smaller than S. araneus. S. minutissimus is the first find in China. Based on different position of the mental foramen, it can be distinguished from S. minutus. S. cf. mirabilis is the first fossil record of this species. Combining previously reported Sorex fossils across China, it seems that more species may have existed. The number of fossil Sorex species cited to date from China has increased to 5.

High-latitude diversification within Eurasian least shrews and Alaska tiny shrews (Soricidae)

A novel shrew was discovered recently in Alaska and described based on morphological characters as Sorex yukonicus. This species is closely allied to Sorex minutissimus, a widespread shrew ranging through Eurasia. Together their distribution spans Beringia, a large Pleistocene nonglaciated area that connected Asia and North America. Beringia was repeatedly divided due to raised sea levels during Pleistocene interglacials and subsequently reconnected during glacials. We tested predictions related to the influence of large-scale geologic events on genetic variability through a phylogeographic analysis of both species of shrew using evidence from 3 independent genetic loci. We found low genetic divergence between S. minutissimus and S. yukonicus across continents. However, major phylogeographic breaks were found for Eurasian and Maritime Northeast Asia populations. Neither species is reciprocally monophyletic for any of the loci examined. Coalescence times for all pairwise population comparisons within both species fall within the Wisconsinan–Weichselian glacial (,130 thousand years ago), and significant population expansion estimates date to the Holocene suggesting that divergence between these taxa is minimal and may not warrant recognition of 2 distinct species. Phylogeographic relationships and sequence divergence estimates place populations of North American S. yukonicus and Siberian S. minutissimus as most closely related, and together they are sister to European S. minutissimus. We conclude that populations east and west of the Bering Strait represent a single Holarctic species, S. minutissimus. Temporal changes in range based on ecological niche predictions and a comparative assessment of other codistributed taxa provide a preliminary view of potential Last Glacial Maximum refugia in northern Asia. DOI: 10.1644/09-MAMM-A-402.1.

Novel Hantavirus in the Flat-Skulled Shrew (Sorex roboratus)

Genetically distinct hantaviruses have been identified recently in multiple species of shrews (Order Soricomorpha, Family Soricidae) in Eurasia and North America. To corroborate decades-old reports of hantaviral antigens in shrews from Russia, archival liver and lung tissues from 4 Siberian large-toothed shrews (Sorex daphaenodon), 5 Eurasian least shrews (Sorex minutissimus), 12 flat-skulled shrews (Sorex roboratus), and 18 tundra shrews (Sorex tundrensis), captured in the Sakha Republic in northeastern Siberia during July and August 2006, were analyzed for hantavirus RNA by reverse transcription-polymerase chain reaction. A novel hantavirus, named Kenkeme virus, was detected in a flat-skulled shrew. Sequence analysis of the full-length S and partial M and L segments indicated that Kenkeme virus was genetically and phylogenetically distinct from Seewis virus harbored by the Eurasian common shrew (Sorex araneus), as well as all other rodent-, soricid-, and talpid-borne hantaviruses.

Diets of the Eurasian Least Shrew (Sorex minutissimus) from Various Localities in Hokkaido, Japan

Diets of the Eurasian Least Shrew (<i>Sorex minutissimus</i>) from Various Localities in Hokkaido, Japan

Insectivores (Soricomorpha, Mammalia) from the Pliocene and Pleistocene of Transbaikalia and Irkutsk region (Russia)

Remains of Talpidae and Soricidae have been found in Pliocene and Pleistocene sediments of 10 localities in Western Transbaikalia and the Irkutsk Region. They belong to five genera and 15 species. Besides fossil ( Petenyia sp., Sorex palaeosibiriensis) and Recent taxa ( Asioscalops altaica, Crocidura sp., Neomys fodiens, Sorex minutissimus, Sorex minutus, Sorex roboratus, Sorex cf. isodon and Sorex cf. daphaenodon) known from Asia, descriptions of two Sorex species from the Baikal region ( Sorex erbajevae and Sorex baikalensis) are given. Thus, the number of fossil Sorex species cited to date from Asia has increased to 21.

Late Pleistocene small mammals from the Wannenköpfe volcanoes (Neuwied Basin, western Germany) with remarks on the stratigraphic range of Arvicola terrestris

Redeposited loess sediments from a Pleistocene crater filling in the Neuwied Basin (western Germany) yielded a small mammal fauna mainly composed of arvicoline rodents. The occurrence of rare faunal elements such as Sorex minutissimus, Sicista subtilis, and a species of Microtus (Terricola) is remarkable. Based on the evolutionary level of Arvicola terrestris, the biostratigraphic age of the fossiliferous horizon is transitional between late Eemian and early Weichselian. This conclusion is partly supported by the generalized ecological requirements of a few dominant rodent species. The fauna contributes to the knowledge of this time period, which is poorly documented in western Germany. A new character of the m1 is proposed for the discrimination of Sicista betulina and S. subtilis. To avoid further confusion in the specific assignment of transitional Arvicola specimens from the late Middle Pleistocene to early Late Pleistocene, we propose the formal taxonomic boundary between chronospecies A. mosbachensis and A. terrestris to be shifted from SDQ value 100 to SDQ value 120.

New data on Soricomorpha (Lipotyphla, Mammalia) from the Pliocene and Pleistocene of Transbaikalia and Irkutsk Region (Russia)

Remains of five genera and 14 species (Talpidae and Soricidae) have been found in the Pliocene and Pleistocene sediments of ten localities in Western Transbaikalia and Irkutsk Region. Besides fossil (Petenyia sp., Sorex palaeosibiriensis) and Recent taxa (Asioscalops altaica, Crocidura sp., Neomys fodiens, Sorex minutissimus, S. minutus, S. roboratus, S. cf. isodon and S. cf. daphaenodon) known today from the Asiatic continent, two new fossil Sorex species (S. erbajevae and S. baikalensis) have been described. Thus, the number of fossil Sorex species cited so far from Asia (16) increased to 21.

Sorex minutissimus captured in Daisetsuzan area of central Hokkaido

Sorex minutissimus captured in Daisetsuzan area of central Hokkaido

Sorex minutissimusの同定基準(森林野生動物研究会創立30年記念集)

Sorex minutissimusの同定基準(森林野生動物研究会創立30年記念集)