Ground beetle fauna (Coleoptera, Carabidae) of Mordovia State Nature Reserve (Russia)

Abstract Background Protected areas are organised in different climatic zones, which usually include typical ecosystems characteristic of certain climatic zones. In most cases, protected areas are biodiversity hotspots. These areas are benchmarks in terms of nature conservation and to determine their biological diversity is becoming an important task. It is important to investigate the carabid family of protected areas within the framework of understanding the overall biological diversity of these systems. In addition, ground beetles, as one of the largest groups of ground-based inhabitants, are indicators of the state of ecosystems and serve as markers of their well-being. New information We present 2,969 new occurrence records comprising 226 species of Carabidae, belonging to eight subfamilies, from the Mordovia State Nature Reserve (central Russia). Ten species are listed for the first time for the Mordovia State Nature Reserve fauna after previous research: Cicindelamaritima, Bembidionstriatum, Dyschiriusangustatus, Dyschiriusarenosus, Notiophilusaestuans, Bembidionargenteolum, Bembidionvelox, Bradycelluscaucasicus, Cymindisangularis and Syntomustruncatellus, five of which were first recorded for the Republic of Mordovia (Egorov et al. 2020). Previously, this information was not published anywhere and we wanted to make it available to everyone by embedding it in the global database on biodiversity (GBIF).


Introduction
Anthropogenic disturbances, such as urbanisation, toxic chemical pollution, more frequent and intense fires, deforestation and climate change have recently had a significant impact on biodiversity in many ecosystems. Insects play an important role in the functioning of ecosystems and a decrease in their biodiversity can cause serious disruptions of natural processes. However, there is a lack of data on the diversity, abundance, phenology and other biological traits of many insect groups that play a crucial role in ecosystems (Butchart et al. 2010, Bondarenko et al. 2020. Ground beetles (Coleoptera, Carabidae) are important predators of other insects and are considered economically useful in agricultural systems (Sklodowski and Garbalinska 2011, Ruchin et al. 2019, Rozhnov et al. 2019. As ground beetles are diverse and abundant in the ground layer of landscapes with varying degrees of disturbance, they have been used as bioindicators to assess ecosystem health (Rainio and Niemelä 2003, Noordijk et al. 2008, Venn et al. 2013, Zamotajlov et al. 2019). Thus, documenting ground beetle diversity and distribution in natural ecosystems, such as the Mordovia State Nature Reserve, provides critical baseline data that can be used for future comparisons with more disturbed sites. Additionally, these data can be used in bioindication, for a general understanding of ecosystem biodiversity and for the protection of individual species and ecosystems.
From the published dataset, five taxa are recommended for inclusion in the Red Data Book of the region (Carabus nitens, Calosoma inquisitor, Carabus aurolimbatus, Carabus schoenherri and Lebia marginata). These are rare and protected species. At the same time, Lebia marginata was found within the region only within the territory of the Mordovian Reserve.

Sampling methods
Study extent: The Mordovia State Nature Reserve is located in the Republic of Mordovia (Central Russia). Its area is 321.62 km . Forests cover 89.3% of the Mordovia State Nature Reserve. The main type of forest is pine (Pinus sylvestris) forests. Pure and mixed stands of pine dominate the southern, central and western parts. Birch (Betula pendula) forests grow in burned areas and are the second most common forest type. Deciduous forests with Quercus robur and Tilia cordata are located in small areas in the northern, western and south-western parts. Small patches of forest, dominated by Picea abies and Alnus glutinosa, are located mainly in the floodplains of small rivers and streams (Khapugin et al. 2016, Ruchin andMakarkin 2017).
Quality control: Each observation includes fundamental information, such as location (latitude/longitude), date, name of observer and name of the identifier. Coordinates were determined on site with a GPS device (various models of smartphones) or after the fact using Google Maps. We used conventional methods for collecting ground beetles, including hand-collecting, pitfall traps, light trapping and partial beer traps (Golub et al. 2012. Pitfall traps (the primary method) were deployed during April-August (sometimes September) 2008-2020. The traps were 0.5-litre cups containing 200 ml of 4% formalin solution. In each habitat, we installed 10 traps along a transect with 2-3 m between consecutive traps. The collected material was determined by S. Alekseev and L. Egorov. Determination was carried out according to Isaev (2002), MÜLLER-MOTZFELD (2004). We followed the nomenclature proposed in Kryzhanovskij et al. (1995), Lobl and Lobl (2017).

Geographic coverage
Description: The dataset provides new records of Carabidae (Coleoptera) from the territory of the Mordovia State Nature Reserve (Russian Federation).