New records and range expansion of Calosoma sycophanta (Linnaeus, 1758) (Coleoptera, Carabidae) in Western Siberia, Russia

In this study, we report about 25 records of Calosoma sycophanta (Linnaeus, 1758) from Western Siberia collected in the last 21 years (1997–2017). We extend the known distribution of this species in the Tyumen, Kurgan, Omsk and Novosibirsk regions of Russia. New records extend the known distribution of C. sycophanta for 300 km to the north, and for 600 km to the east, in the Western Siberia. These new distributional data may contribute to a re-evaluation of its conservation status.


Introduction
The forest caterpillar hunter, Calosoma sycophanta (Linnaeus, 1758) (Figs 1, 2), a member of the family Carabidae, is distributed in the Western Palearctic.The range of this species covers the whole of Europe, northwest Africa, Western and Central Asia (Kryzhanovsky 1981, Kryzhanovsky et al. 1995, Kryzhanovsky and Obydov 2001, Bespalov et al. 2010).
This entomophagus predator has been introduced in North America for forest pest control, where it has successfully established and is now expanding its range (Evans 2009).In some countries it is reproducing very successful (Kanat and Mol 2008).Despite this, in many countries and regions (e.g.Czech Republic, Poland, Germany, Russia, Ukraine and Azerbaijan), populations of this beetle are small and continue to decline, and in these counties, this species is protected.Due to its large size, bright color, practical significance, and conservation value, this species of beetle is well-known.
The north-eastern border of the Asian part of the area is currently not well-known (Bespalov et al. 2010).By the 1990s, C. sycophanta was located along the southern Ural Mountains and in western Kazakhstan (Kryzhanovsky 1981(Kryzhanovsky , 1983)), where it is still relatively common (Yashchenko andMityaev 2005, E.V. Zinoviev 2018 pers. comm.).The northernmost specimens were found in the central Ural Mountains (Sverdlovsk oblast) between 1989 and 1996 in the vicinity of the cities of Asbest, Yekaterinburg, Belorechensk (Fig. 3) (Voronin 1999).The easternmost specimens were found in the southwest of Western Siberia in the Trans-Ural regions (Kurgan oblast) (Kalinin 1985, Molchanov 1989, Utkin 1999,

2
Utkin and Balahonova 2012).The south-eastern border of the area is formed by the mountains of Central Asia.
In the east, the distribution of C. sycophanta is limited to northeastern Kazakhstan, northwestern Mongolia, and a southwestern Altai within Russia (Jacobson 1905-1915, Breuning 1927, Kryzhanovsky 1981, 1983, Kryzhanovsky and Obydov, 2001, Bespalov et al. 2010).The latest records of C. sycophanta in Altai Krai (Zmeinogorsky district) were found in 1990 and 2001 (Obydov 2010) (Fig. 3).Calosoma sycophanta was not found in the dry steppes and deserts of central Kazakhstan.Thus, in the Asian part of its range, this species area occurs in 2 areas -a northern area, running through the southern Ural Mountains and Western Siberia, and a southern area, which includes the mountainous regions of Central Asia, Altai, and northwestern Mongolia (Fig. 3, inset).However, since the late 1990s there has been a large number of new records of this species in the territory of Western Siberia, including some from a considerable distance from its previously known range.These records were partially published in various local and regional natural history journals.An annotated list of all records, both new and previously published, and a discussion of possible reasons for the increase in the number and expansion of the area of C. sycophanta in the Asian part of Russia is given below.

Methods
We studied the collections of the Zoological Museum of Tyumen State University (Tyumen), the Museum Complex of Slovtsov (Tyumen), the Siberian Zoological Museum (Novosibirsk), private collections of M.A. Ananin and A.V. Litvinov (both amateur entomologists), and photographs and observations by local residents and naturalists.All literature was critically examined.The originals of rare and difficult-to-find publications were especially searched for.
Of the new material that we collected, most of the specimens were collected by hand.In some cases, beetles were caught in soil traps and cages with gypsy moth larvae.For some, only typical fragments of sclerotised elytra were found.

Results
Records.All records of Calosoma sycophanta in Western Siberia from the last 21 years  are listed in chronological order in Table 1.Many of the records were previously published, but mostly in local natural history journals and often with incomplete data.Other records are new, published here for the first time.Figure 3 maps these records; numbers correspond to records in Table 1.
Identification.Body length is 21-33 mm.Head and pronotum dark blue or blue-green.Elytra golden-green with copper-red tint, sometimes copper-red.Antennae and legs black.Wings are developed, capable of flying.The color of this species differs from other species Calosoma in Eurasia.

Discussion
Table 1 shows that Calosoma sycophanta significantly has expanded the northeastern edge of its range since the late 1990s (Fig. 3).Previously in the Asian part of Russia only a few records existed in the very south-west of that region and 1 record in the Altai.However, over the last 20 years, 24 new records were made in the plains and an another record for the Altai mountains.In addition, records of this species are becoming more northern, penetrating into the boreal zone.There is also an expansion of the range to the east.Early records of C. sycophanta were noted for Kurgan and Tyumen oblasts but since 2009, it has been recorded in the Omsk oblast, and since 2010, in eastern Novosibirsk oblast.The edge of the range has expanded 300 km to the north and 600 km to the east.It is probable that soon beetles from the 2 population areas (Eastern European-Trans Ural Mountains populations and Altai) will meet and the range of this species will become connected.
In some of the new locations, the number of individuals of C. sycophanta was very high.According M.E.Yurin, to a forest ranger of the Omutinsky Forest District of Tyumen region, in recent years this species occurs very often in the forests of that district (E.S. Bayanov 2016 pers. comm.).This species is now also common in the Kurgan oblast (Balahonova 2009), but no specific occurrence data were given.
The expansion of the range of C. sycophanta area has been noted in other regions as well.In North America, where the species was introduced in 1906 and 1907 to control the gypsy moth, its area continues to expand (Schaefer et al. 1999, Evans 2009).In eastern Kazakhstan (in the eastern part of the range) in recent years, several new records of this species have been noted (Bespalov et al. 2010).
As a reason for the increased number of records and the expansion of the range of C. sycophanta, we assume that global climate change is responsible.Earlier, since the edge of the 20th century and beginning of the 21st century, both in Europe and in Western Siberia, many steppe arthropod species, such as Argiope bruennichi (Scopoli, 1772), Mantis religiosa (Linnaeus, 1758), and Phaneroptera falcata Poda, 1761, have expanded their ranges to the north (Liana 2007, Bolshakov et  Calosoma sycophanta is an active predator, an entomophagus, feeding mainly on the larvae of 2 serious forest pests, the Gypsy Moth Lymantria dispar (Linnaeus, 1758) and the Nun Moth L. monacha (Linnaeus, 1758).Kryzhanovsky and Obydov found that population numbers of Calosoma are fluctuate highly depending on the number of Gypsy Moths.Since the end of the 20th century there has been an increase in the population numbers and ranges of both the gypsy Moth and Nun Moth in Russia, but primarily in Siberia, where they previously were not widespread (Gninenko 2000, Titkina et al. 2013, Yasyukevich et al. 2013).
Most of new records of C. sycophanta have been made in places of mass outbreaks of moths, at least in the most northerly locations.Thus, in the Kazansky district (record no.18), a very high abundance of imagines and larvae of C. sycophanta was noted (A.S.Afonin pers.сomm.2016).On repeated visits to the same locality on July 20, 2016 and July 31, 2017, Gypsy Moth numbers were very low, and C. sycophanta was not found.The records of C. sycophanta made in 2017 from the vicinity of the Lake Kuchak biostation of Tyumen State University (Nizhnetavdinsky district of Tyumen oblast) are significant in this regard.Since regular entomological monitoring in this area began in 1993 and until 2016, C. sycophanta had not been found.In 2016 a large Gypsy Moth outbreak occurred in this region, which in 2017 caused a mass deformation of the leaves of aspen and birch.In that year, during the outbreak, a male and a female of C. sycophanta were found.Unlike most other large ground beetles, C. sycophanta flies well (Kryzhanovsky 1983, Knyazev 2015).This allows this species to quickly follow its main prey object.Thus, we conclude that significant increases in the abundance of C. sycophanta and the expansion of its range to the north and east in Western Siberia is indirectly caused by global climate change, because of the expansion of the range of its main prey, the Gypsy Moth.

Table 1 .
(Aleksandrowicz 2011)olbovet al. 2016), as a result, it is thought, of aridization brought about by climate change.These range expansions look similar to what is now happening with Calosoma sycophanta.The northward expansion of a number of steppe ground beetles, including species of the genus Calosoma, has been noted in recent years in Belarus(Aleksandrowicz 2011), and the increase in the average annual temperature due to global climate change and human economic activity were noted as the main causes.
Figure 3. Dynamics of the distribution of Calosoma sycophanta (Linnaeus, 1758) in Western Siberia.Numbers correspond to the records in Table 1.Top right: the area in Palearctic (dark fill) (Krizhanovskii 1983).