Checklist of rodents and insectivores of the Crimean Peninsula

Abstract A dataset comprising 6806 records is presented of 17 (of total 24) rodent and insectivore species from the Crimean Peninsula collected during a 35-year period. All records are stored in the Public Mammal Database (Mammals of Russia; http://rusmam.ru/). The density of occurrence points allows visual evaluation of species distribution, even on large-scale maps. Each record contains the species name, locality description, and geographic coordinates, coordinate accuracy, date and author of the record, data source, and the method of species identification.


Introduction
Small mammals [in particular, Rodentia (rodents) and Eulipotyphla (insectivores)] represent one of the most substantial components of the majority of terrestrial ecosystems. Being among the most diverse and abundant mammalian orders, rodents and insectivores play a critical role in maintaining the ecosystem. They also serve as reservoirs of many infectious diseases of humans, livestock, and wildlife being thus important from the perspective of public health (Evstafiev 2017). It is not surprising that studies of rodent and insectivore diversity and distribution have a long history.
Crimean fauna is heterogeneous and consists of two sharply different groups of species, steppe and mountain (Puzanov 1949). Steppe species penetrated Crimea from the northeast of Black Sea region recently. Mountain fauna is rather autochthonous. Crimean Mountains provided refuge for forest related species during the last glaciation cycle (Markova 2011).
The history of mammalogical studies in the Crimean Peninsula has earlier been described by Dulitskiy (2001aDulitskiy ( , 2001b, whereas the general characteristics of the mammalian fauna of the Peninsula can be found in Nikolskiy (1891), Puzanov (1927), andVshivkov (1966). However, information on rodents and insectivores provided in these publications is purely descriptive. More detailed account of the distribution, ecology, and medical and agricultural importance of these animals in the Crimean Peninsula has been reported by Tovpinets and Evstafiev (Tovpinets and Evstafiev 2010;Tovpinets 2012;Evstafiev 2015Evstafiev , 2016Evstafiev , 2017. However, these publications did not present specific data on all known localities for a given species, while maps and observation lists have geographical uncertainty and lack time references.
Here, we publish a checklist of rodent and insectivore records across the Crimean Peninsula for the first time. This checklist was based on comprehensive surveys of small mammals carried out from 1983 until 2018.
Insectivores are represented in Crimea by six species belonging to two families (Dulitskiy 2001a In general, rodent and insectivore fauna of the Crimean Peninsula is depauperated. For instance, some species that are common in neighboring regions with similar environment such as Taman Peninsula and the northeast of Black Sea coast, are absent from Crimea. These include shrews of the superspecies Sorex araneus Linnaeus, 1758, the greater blind mole rat Spalax microphthalmus Güldenstädt, 1770, and Strands's birch mouse Sicista strandi Formosov, 1931(Stakheev et al. 2017. Species, which are common in the Caucasus Mountains are also absent in mountainous Crimea (voles of the Terricola subgenus, and the dormice Dryomys nitedula Pallas, 1778 and Glis glis Linnaeus, 1766). However, the Caucasian pygmy shrew Sorex volnuchini has recently been found in Crimea (Vega et al. 2020) but we have no information on this species in the current study.
Dendrophile rodents and insectivores are represented by four species only (S. vulgaris, Neomys anomalus, Sylvaemus flavicollis, and Sylvaemus uralensis). Of them, the only true arboreal species S. vulgaris is not an aboriginal Crimean species but has been introduced to the peninsula.
A large group of species is associated with human settlements. Eleven species (Crocidura suaveolens, Sylvaemus witherbyi, Sylvaemus uralensis, Sylvaemus flavicollis, Mus musculus, Rattus norvegicus, Rattus rattus, Microtus obscurus, Microtus socialis, Cricetus cricetus, Cricetulus migratorius) have repeatedly been recorded in residential areas (Evstafiev 2016). However, only three species, the house mouse Mus musculus, Norway Rattus norvegicus and black rats Rattus rattus, are truly commensal. In addition, the common hamster Cricetus cricetus is often found in urban environment, e.g., from the outskirts to the central regions of the city of Simferopol (Surov et al. 2016).

Taxonomic coverage
The dataset contains 6806 records of rodent and insectivore species from the Crimean Peninsula (Table 1).

Temporal coverage
The data were collected from 1983 to 2018.

Method
The major part of the data set was obtained during epizootiological survey of the Crimean Peninsula. Mammals were captured using small spring snap-traps (120 × 55 mm) deposited for one night in a line of 50-100 traps with a distance of 5 m between them and baited with bread and sunflower oil. The voucher specimens are stored in the personal collection N. Tovpinets, Simpheropol (zootonik@gmail. com). Data on Cricetus cricetus, Rattus norvegicus, and Rattus rattus were obtained via direct observations and/or detection of the traces of their activities (tracks, burrows, etc.).

Dataset description
Each record contains species name after Lissovsky et al. (2019), geographic coordinates, description of locality and habitat, coordinate accuracy (in meters), date and author of the record, data source (museum specimen, photo availability etc.), type of information used for species identification (morphology, cytogenetics, genetics, etc.), and relative abundance per 100 traps/nights. The dataset is compiled in the public database 'Mammals of Russia' (http://rusmam.ru/; Lissovsky et al. 2018), where all records are validated by experts.