The ground beetles (Caraboidea) of the southern Sikhote-Alin Mountains

Abstract Background This paper presents the results of 30 years of field studies on the Caraboidea fauna of the southern Sikhote-Alin Mountain, Russian Far East. Material was collected at 300+ geographical localities within 18 administrative and seven urban districts of the Primorsky Krai, Russia. A total of 55,953 adult ground beetles belonging to 426 subspecies, 411 species, 86 genera and three families were studied. The families Rhysodidae and Trachypachidae are represented by one species each, while the family Carabidae the remaining 409 species. The resulting sampling-event dataset includes 12,852 occurrences. New information This is the first dataset underlying an accurate and referenced taxonomic composition, as well as the geographic distribution of the Caraboidea in the southern Sikhote-Alin Mountains, Primorsky Krai, Russian Far East.

other researchers. As a result, a total of 55,953 adult specimens of Caraboidea were studied.
Sampling description: When studying the Sikhote-Alin ground beetles, all available methods for their collection were used: hand-collecting , collecting with an exhauster, pitfall trapping, sweeping the crowns of trees and bushes, catching with conventional and ultraviolet light bulbs, night collecting with flashlight, "trampling" vegetation in humid and swampy habitats, water inundation in places at the edge of the water, sifting the litter with an entomological sieve, "mowing" on the grass with an entomological net, catching with a light trap, Malaise traps and window flight traps (Chapman and Kinghorn 1955, Hardwick 1968, Stewart and Lam 1968, Gillies 1969, Vanhercke et al. 1981, Kryzhanovskij 1983, Schauff 1986, Spence and Niemelä 1994, Dunaev 1997, Yahiro and Yano 1997, Skvarla et al. 2014. When working in stationary conditions, the collection was carried out using the various techniques as described above. During short trips and excursions, manual collection and pitfall trapping were mainly applied.
Our field research was carried out in the following landscapes and habitats:

1.
Low mountains (intrazonal vegetation prevailing). They include the valleys of larger rivers, the sea coast and the peripheral regions of the Sikhote-Alin Mts. The fauna Schematic map of south Sikhote-Alin.
The ground beetles (Caraboidea) of the southern Sikhote-Alin Mountains of low mountains is the richest in terms of taxonomy, but its component species show vast distributions and inhabit the entire territory as a rule (Sundukov 2000, Sundukov 2001b, Sundukov 2010a). There are some differences in the taxonomic compositions of the eastern and western macro-slopes of the Sikhote-Alin, since many boreal species penetrate much further south along the sea coast. To identify the species composition of this zone, it seemed sufficient to carry out field research at localities rather distant from one another.

2.
Middle mountains (oak forests, cedar-broadleaved and dark coniferous forests are the most remarkable amongst the zonal vegetation communities). They take up the main part of the southern Sikhote-Alin area. The fauna is rich and includes species both widespread and numerous endemics and relics of various ranks (Berlov and Berlov 1996, Berlov and Berlov 1999, Sundukov 1999, Sundukov 2019a, Sundukov 2019b. When studying the fauna of the middle mountains, the latitudinal factor is of great importance: in the northern part of the southern Sikhote-Alin, species of the boreal complex take a significant part, whereas in the extreme south, species of the East Asian nemoral fauna predominate. For a sufficiently complete survey of this zone, research is required in at least three parts: northern, middle and southern.

3.
Highlands (subalpine and alpine belts). In the south of Sikhote-Alin, such habitats are poorly developed, being represented by separated "islands" on tops of the highest mountains and ridges. Highlands support poor, but the most original faunas of ground beetles, including a large number of narrow endemics (Farkač and Plutenko 1992, Uéno and Lafer 1994, Farkač and Plutenko 1996, Sundukov 2001c, Sundukov 2009c, Sundukov 2010b, Sundukov 2019b, Sundukov 2019a. Surveying the southern Sikhote-Alin highlands must be carried out totally through visiting almost every peak towering above the upper timber line. Quality control: All collected specimens have been identified by the authors. The taxonomy and names of taxa are given in accordance with the Catalogue of Palaearctic Coleoptera (Löbl and Löbl 2017).

Geographic coverage
Description: The southern Sikhote-Alin is located in the extreme southeast of the mainland of Russia within the Primorsky Krai. According to the accepted physiographical zonation of the Far East, it occupies the southern part of the province of the Sikhote-Alin Mountains in the Amur-Primorsky landscape country (Parmuzin 1964, Ivashinnikov 2010. The surveyed territory is part of the vast mountainous Sikhote-Alin country lying between 42.8°-46.1° N and 131.8°-136.8° E (Fig. 1). Both from north to south and from west to east, the extent is about 400 km.
By its relief, the southern Sikhote-Alin is a typical mid-montane landscape. Its elevations average 600-1000 m above sea level, individual peaks up to 1600-1800 m a.s.l.
(Oblachnaya, 1856 m a.s.l.; Snezhnaya, 1682 m a.s.l.; Sestra, 1671 m a.s.l.; Olkhovaya, 1669 m a.s.l.). The highest peaks are sharply outlined, being covered with stony screes over vast areas as a rule. In addition to the main watershed ridge, the orographic composition of the southern Sikhote-Alin includes seven almost parallel ridges stretched mainly from southwest to northeast along the coast of the Sea of Japan (Fig. 1)  In the southern Sikhote-Alin, forest vegetation prevails, occupying about 97% of the territory (Petropavlovsky 2004). By origin, three forest groups can be distinguished: successional (communities formed in river floodplains) (Fig. 2a, b), virgin (represented only by fir-spruce forests of the upper mountain belt and alpine vegetation) (Fig. 2c, d, e) and a b c d e f Figure 3.  (Fig. 3c, d), meadows (Figs 3e, f, 4a), bogs (Fig. 4b), subalpine shrubs (Fig. 4d), mountain meadows (Fig. 4c) and tundra (Fig. 4e, f), all occupying small areas. A characteristic feature of the vegetation of the southern Sikhote-Alin is a well-pronounced zonation which is due to the elevation above sea level, the geomorphological structure of the surface and the influence of the sea.   In addition, information about collection material collected in other years or received from other collectors, which are stored in the collection of the author, is included. In total, the dataset include information on 55953 specimens of adults of ground beetles belonging to 411 species from 86 genera and three families of Caraboidea. They are distributed between families as follows: Rhysodidae -one species, Trachypachidae -one species and Carabidae -409 species.

Coordinates
The dataset consists of one

Author contributions
Yu. Sundukov -collection and identification of the majority of ground beetles, analysis of literature, data preparation. K. Makarov -collecting and identifying a minor part of ground beetles, preparing data uploading to GBIF, editing.