New and interesting findings of scarab beetles (Coleoptera, Scarabaeoidea) from Tajikistan

Abstract We report on new findings of nearly 50 species that represent four families of the superfamily Scarabaeoidea, which were collected during an expedition to western Tajikistan that was carried out in June and July 2014. Rhyssemodes transcaspicus Rakovič, 1982 is recorded from the country for the first time. Moreover, we describe and illustrate the differences in the external morphology between Euonthophagus gibbosus (Scriba, 1790) and E. koshantschikoffi (Reitter, 1891), the latter of which has a doubtful systematic position. In the collected material of approximately 1,000 specimens, more than 90% of the species and 95% of the individuals belong to the family Scarabaeidae. The other species represent the families Geotrupidae, Glaphyridae, and Hybosoridae.


Introduction
The first comprehensive study that contained information on the scarabaeoid beetle fauna of Tajikistan was presented by Medvedev and Lopatin (1961), who reported on 183 species in the country but provided scant data on habitats, biology, and distribution. More information on the local Scarabaeoidea of the subfamilies Melolonthinae, Rutelinae, and Dynastinae, as well as on the family Glaphyridae, can be found in the earlier monographs of the notable "Fauna SSSR" series (Medvedev 1949(Medvedev , 1951(Medvedev , 1952(Medvedev , 1960 and on the subfamilies Cetoninae and Valginae in the later continuation of this series (Medvedev 1964). These works also contain identification keys to species. Additionally, some information on the scarabaeoid beetles of the subfamily Aphodiinae that occur in Tajikistan was included in the studies of Protzenko (1968), Nikritin (1973), and Nikolajev (1987). Nikolajev (2003) published another work of a great importance for recognising the fauna of the family Geotrupidae; the paper included species of the genus Lethrus Scopoli, 1777 (Lethrinae), which constitutes a significant share in the local beetle fauna. Three years later, an extensive monograph containing comprehensive information on the subfamily Scarabaeinae (Scarabaeini, Gymnopleurini, Onthophagini, Onitini) of Russia and adjacent countries, including Tajikistan, was released (Kabakov 2006). According to the latest edition of the Catalogue of Palaearctic Coleoptera, 274 species of scarabaeoid beetles are currently known from Tajikistan (Löbl and Löbl 2016).
The majority of the works on the Scarabaeoidea of Tajikistan were published in the last century. They treat the scarabaeoid Tajik fauna in the context of areas that often reach far beyond the current boundaries of the country, and sometimes even beyond the commonly accepted borders of Central Asia. Consequently, many records have a rather general character without any precise locality data. Therefore, we aim to supplement the current information on the distribution of the taxa of the superfamily Scarabaeoidea in the country. An additional goal of our study is to gather and disseminate information contained in valuable publications that are, however, difficult to access and were usually published exclusively in Russian.

Material and methods
Tajikistan is a relatively small intra-continental country that is situated at the boundary of the subtropical and temperate climatic zones. It is located in the mountain desert zone of the Eurasian continent, in the southern part of Central Asia. In this region, diverse ecosystems such as deserts, steppes, conifer forests, mixed mountain forests, and high-mountain deserts are widely represented. The formation of this unique biological diversity in the country, which counts numerous endemic and relict species, is due to the varied mountain climatic conditions and historical natural processes (Safarov 2003).
An entomological expedition, which consisted of four scientists from the former Department of Zoology, University of Silesia in Katowice (Poland), was undertaken over 25 days from 24 June to 18 July 2014. During the research, several field surveys in various locations in the western part of Tajikistan were conducted (Fig. 1). The most extensive studies were carried out in the central part of the region and in the southwestern part of the country along the Afghanistan border. Our investigations were conducted in several research plots including the villages or environs of Arykboshi, Dushanbe, Dohanaklik, Ganchi, Gharm, Iskanderkul, Jilikul, Kangurt, Karatag, Komsomolabad, Kulob, Nurobod, Romit, Sarichashma, Shahrinav, Shurroabad, Takob, Tojikobod, and Vose (Table 1).
The area covered by our study includes several different nature ecosystems such as alpine meadows, mesophilic shrubs, shrub steppes, broad-leaf forests, and tugay, as well as agroecosystems such as gardens, orchards, fields, and pastures (Figs 2, 3). Various field methods were used because scarabaeoid beetles comprise species with a very diverse biology. However, because coprophagy is the main type of feeding behaviour in this group, most of the sampling took place in pastures and semi-desert areas where dung of domestic and wild animals was examined (Fig. 2E). Additionally, beetles were attracted to the artificial light sources during the night.
Beetles were photographed in their habitats with Canon EOS 550D, Canon EOS 600D, and Olympus XZ-1 cameras. Mounted specimens were imaged using a Leica  M205C stereomicroscope with Leica LED5000 HDI high-diffuse dome illumination and equipped with a Leica DFC495 digital camera. The images that were produced were stacked, aligned, and combined using Leica application suite v. 4.9.0 software. The images selected were cleaned, retouched, and arranged into figures using Adobe Photoshop CS6 software. The geographical coordinates were recorded using a Garmin Oregon 550T 3-Inch Handheld GPS Navigator. For each specimen that was collected, the exact location, altitude, date, and the names of the collectors are given. All the specimens listed below were collected by Artur Taszakowski (AT), Lech Karpiński (LK), Marcin Walczak (MW), and Wojciech T. Szczepański (WTS). Taxa were identified by Adam Byk (AB), Andrzej Matusiak (AM), and Marek Bunalski (MB). The specimens are preserved in the entomological collection of the Department of Natural History of the Upper Silesian Museum, Bytom, Poland (USMB) and in the collections of the authors. The systematic arrangement and nomenclature were adopted from the Catalogue of Palaearctic Coleoptera (Löbl and Löbl 2016).

Results
As a result of this study, about 950 beetles belonging to 48 species in four families of the superfamily Scarabaeoidea were collected: Geotrupidae (1 sp.), Glaphyridae (2 spp.), Hybosoridae (1 sp.), and Scarabaeidae (44 spp.), including Scarabaeinae (17 spp.), Aphodiinae (12 spp.), Melolonthinae (5 spp.), Cetoniinae (5 spp.), Rutelinae (3 spp.), and Dynastinae (2 spp.). The list of the recorded taxa along with their new localities is presented below.  Remarks. Three species from the subgenus Mesolethrus Nikolajev, 2003 were recorded from Tajikistan, and another two from the neighboring Uzbekistan (Bagaturov and Nikolajev 2015). Females of these species are extremely similar and thus almost unidentifiable. The determination was additionally hindered by significant degree of body damage of our specimens. Remarks. This species occurs in Uzbekistan, southern Turkmenistan, northeastern Iran, and northern Afghanistan. In Tajikistan, it was reported from a number of localities: Mumilabad, Kulab, Langar, Darvaz (Medvedev 1960). This is an early spring species, which is usually found from March to May (Medvedev 1960;Medvedev and Lopatin 1961).
We collected it at the end of June in high mountain meadows near Romit and Takob. Two individuals were found on flowers of herbaceous plants.

Remarks. Glaphyrus turkestanicus is distributed in Uzbekistan, Afghanistan (Medve
We collected a single male of this species in a mountain meadow near Shurroabad. The beetle was found inside a calyx of Carduus sp. (Fig. 3F).  Remarks. This species has been reported from Uzbekistan and the southern territory of European Russia. According to Rakovič and Král (2015), its presence in Uzbekistan is confirmed by the holotype's label: "Golodnaya Step" (about 120 km southeast   (2007) and Shokhin et al. (2014). Although Rh. transcaspicus had been synonymised with Rhyssemodes tenuisculptus Reitter, 1892 by Nikolajev (1987), it was restored 15 years later by Shokhin (2002). We collected 16 individuals of Rh. transcaspicus at three different sites in the western part of the country, about 300 km south of its type locality. All individuals were found near human settlements with semi-arid (environs of Jilikul) and farmland (environs of Kulob and Chavrok) habitats in the immediate vicinity. In all cases, imagines were attracted to UV light. This is the first record for Tajikistan. The material was additionally verified by Łukasz Minkina (Poland). Remarks. This is a widely distributed species known from the southern part of the European territory of Russia, Georgia, Armenia, Azerbaijan, Iran, and Afghanistan; it is also widespread in Central Asia: Turkmenistan, Uzbekistan, and Tajikistan. Moreover, it was reported from Syria, Turkey, and Greece (Kabakov 2006), as well as from Cyprus, Lebanon, and Israel (Bezděk 2016c). In Tajikistan, it has been recorded from numerous localities, such as Dushanbe, Gissarskiy Khrebet, Vakhshkiy Khrebet, Khoviling, and Darvaz (Medvedev and Lopatin 1961).
We found most individuals in cow and horse dung in warm and dry meadows at altitudes from 500 to 1050 m a.s.l.

Remarks.
We collected a series of individuals belonging to E. koshantschikoffi, a taxon with a uncertain systematic position. This species was described from the environs of Tashkent, Uzbekistan, under the name Onthophagus koshantschikoffi Reitter, 1891, and its range is limited to Central Asia. In 1972, this species was recognised as a junior synonym of Onthophagus gibbosus (Scriba, 1790), a much more widely distributed species which was described from southern Germany (Zunino 1972). Five years later, Kabakov (1977) maintained this synonymisation and added the area of the occurrence of O. koshantschikoffi to the distributional range of O. gibbosus. Nearly 30 years later, Kabakov (2006) gave this taxon the rank of subspecies-O. gibbosus koshantschikoffi-and indicated several morphological characters for distinguishing it; Kabakov (2006) once again demarcated the distributional range of O. gibbosus koshantschikoffi while pointing out that it occurs only in the south-eastern part of the species' range. On the other hand,

Character
Euonthophagus gibbosus (Fig. 6A-C) Euonthophagus koshantschikoffi (Fig. 6D-G) Head in males frontal suture arcuately widening towards lateral edges (frontal view), located near clypeus edge (Fig. 6B, C) frontal suture not widening towards lateral edges (frontal view), located clearly further from clypeus edge, about half of length of head (Fig. 6F, G) Pronotum surface matte, rarely with barely noticeable gloss (Fig. 6A) surface clearly shiny (Fig. 6D, E) Elytra surface matte, black, very rarely brown or reddish-brown (in the studied material all of the individuals were uniformly black) (Fig. 6A) surface slightly shiny, black or reddish-brown (in the studied material approx. 75% of the specimens had a light-coloured elytra) (Fig. 6D, E) Material examined 64 exx.; Georgia, Armenia, Turkey, Greece, Albania and Spain 55 exx.; Tajikistan (collected in six different localities) according to Löbl et al. (2006), Shokhin et al. (2014), and Ziani and Bezděk (2016), this taxon is a separate species, as Euonthophagus koshantschikoffi, but these authors gave no comments that would justify the restoration of a specific status for this taxon.
In considering the general distribution of these taxa and the differences in their morphology (Table 2), we support the position of Löbl et al. (2006), Shokhin et al. (2014), and Ziani and Bezděk (2016) that E. koshantschikoffi is a valid species and recognize as such. We emphasize, however, that the systematic position of these two taxa requires further research, including study of specimens from their contact zone, preferably using molecular methods. Remarks. The species is widely distributed in Central Asian countries, in Iran and Afghanistan (Kabakov 2006). It was recorded from Kazakhstan, Uzbekistan, Kyrgyzstan, Turkmenistan and Pakistan by Ziani and Bezděk (2016). In Tajikistan, it was noted inter alia from Argankun, Vakhshkiy Khrebet, Beshkentskaya Valley, Chiluchor Chashma, Darvaz (Medvedev and Lopatin 1961). This is a rather common species that mainly occurs on loess and sandy soils and it reaches the altitude of 3000 m a.s.l. (Kabakov 2006).

Euonthophagus sulcicollis (Reitter, 1892)
We found 17 individuals in cow dung in rather warm sites in mountain pastures and semi-desert habitats.

Remarks.
Onthophagus haroldi is mainly distributed in Central Asia and Kazakhstan, in northeastern Iran, northern Afghanistan, and in the Xinjiang Autonomous Region of China (Kabakov 2006). In Tajikistan, Medvedev and Lopatin (1961) recorded it from the vicinity of Dushanbe, Vakhshkiy Khrebet, Beshkentskaya Valley, and Chiluchor Chashma.
We found a single individual in cow dung on a south-facing grassy slope. Remarks. This species occurs in the southernmost parts of Kazakhstan, Kyrgyzstan, and mountainous regions of Uzbekistan and Tajikistan; it has also been reported from Afghanistan by Kabakov (2006). Although it has been recorded from Syria, Turkey, Armenia, and Azerbaijan (Ziani and Bezděk 2016), these data most probably relate to another species, O. formaneki Reitter, 1897 (Kabakov 2006). We found four individuals of O. basipustulatus in cow dung.  Remarks. The species is widespread in Central Asia, from Köpet Dag mountain range in Turkmenistan to the Russian-Chinese border. The northern boundary of its distributional range is limited by the foothills of Tian Shan. It also occurs in Armenia, Iran, Afghanistan, and China (Xinjiang) (Kabakov 2006). In Tajikistan, O. pygargus is very common and was recorded from numerous localities including Zeravshanskiy Khrebet, near Marguzor Lake, and Gissarskiy Khrebet, Khozretisho (Medvedev and Lopatin 1961).

Onthophagus
We found this species to be one of the most frequently occurring dung beetles in our field survey. We collected it in large numbers in many localities, both in mountain and other pastures near highly urbanized areas. It was found in cow, horse, and sheep dung. Remarks. Scarabaeus carinatus inhabits mountains of Central Asia and Afghanistan; it is known from Turkmenistan, Uzbekistan, Tajikistan, and Kyrgyzstan. This species has also been recorded from southern and western Kazakhstan (Kabakov 2006) and Iran . It prefers mountain valleys to 3200 m a.s.l. (Kabakov 2006).
We found four individuals in cow dung in mountain pastures.

Subfamily Melolonthinae Leach, 1819
Polyphylla ( Remarks. The species has been reported from southeastern Uzbekistan, northwestern Tajikistan, and western Kyrgyzstan (Medvedev 1951). In Tajikistan, it is known from the Nauskiy region, Gissarskiy Khrebet, from the vicinity of Lake Iskanderkul, and in the village Obigarm (Medvedev and Lopatin 1961).
In the valley of a mountain river in the vicinity of Karatag, four males were attracted to a UV lamp. [AT] -4 exx.
Remarks. This species is distributed in Uzbekistan, northern Tajikistan, southern Kazakhstan, and Kyrgyzstan (Medvedev 1949). It has also been recorded from Eastern Siberia and China (Xinjiang) (Zorn and Bezděk 2016). In Tajikistan, Medvedev and Lopatin (1961) reported it from a number of localities, including Dushanbe, Gissarskiy Khrebet, Fayzabad, Muskinabad, Khozretisho, and Khujand, among others. This species inhabits dry steppes, and it is also often found in farmlands (Medvedev 1949). We caught this species in mountain meadows, and it was observed in large numbers. Adults were observed flying over the grass and became more active in the evening. It is worth noting that two color forms, the typical brownish form (Fig. 7G) and a melanistic form, were observed sympatrically. Remarks. Protaetia bogdanoffi was reported from Uzbekistan, Tajikistan, Kyrgyzstan, and Afghanistan (Medvedev 1964), as well as from Kazakhstan (Bezděk 2016a). In Tajikistan, it has been recorded in Zaalayskiy Khrebet (Trans-Alay Range), Darvaz, Gissarskiy Khrebet, and Khozretisho (Medvedev and Lopatin 1961). This species occurs in open areas, such as steppe and semi-desert habitats, and in river valleys, as well as in higher mountains up to 2500 m a.s.l.

Pentodon bidens bidens
The individuals caught in a mountain meadow in the environs of Takob were collected on flowers, most likely of Heracleum or Prangos. Another individual, caught at Chavrok, was attracted to a UV lamp near human settlements, in a typical agricultural landscape.

Discussion
Approximately 17% of the scarabaeoid fauna of Tajikistan was recorded during our 25-day survey, which was conducted from 24 June to 18 July 2014. We found one species, Rhyssemodes transcaspicus, that has not been previously recorded from the country. The occurrence of three species, Cheironitis eumenes, Onthophagus silus and O. ovatus (Kabakov 2006), had been omitted in the second edition of the Catalogue of Palaearctic Coleoptera (Löbl and Löbl 2016). Moreover, Nikolajev and Pak (2020) described from Tajikistan a new species of the genus Trochaloschema (T. dubium Nikolajev & Pak, 2020), and Pak and Gubin (2020) described two new species of the genus Lethrus (L. ahriman Gubin, 2020 andL. asmodeus Pak &Gubin, 2020). Therefore, with these recent publications and our finding of R. transcaspicus in Tajikistan, the number of scarabaeoid species in the country is increased to 281.
The most commonly observed species of pleurostict scarab beetles were Adoretus nigrifrons (35 exx.) and Oxythyrea cinctella (48 exx. Most of the coprofagous Scarabaeoidea of Tajikistan are species whose imagines appear in the spring or at the turn of spring and summer, so the relatively small number of taxa collected is undoubtedly due to the rather late period of our study. Species whose adults start to occur in the summertime constitute less than a half of the scarabeoid beetles of Tajikistan (Medvedev and Lopatin 1961).
Most of the field research on the scarabaeoid beetles of Tajikistan was conducted in the middle of the 20 th century and almost exclusively by Russian entomologists. This was partly caused by the political isolation of the country and partly by the lack of transport and tourist infrastructure. After its separation from the Soviet Union in 1991 and the introduction of tourism facilities, the intensification of research was possible for both scientists and amateur entomologists. This, in turn, undoubtedly contributed to a better understanding of the local entomofauna and in a relatively short time resulted in the description of new species and newly recorded taxa for this country (Novikov 1999;Gusakov 2003Gusakov , 2007Gusakov , 2008Nikolajev 2008;Ivanova 2012;Ivanova and Pak 2012;Akhmetova and Frolov 2014).
The richness of the scarabaeoid fauna of Tajikistan and the geography of the country clearly indicate the possibility of finding further species of this superfamily, in particular in near the borders with neighbouring countries where numerous other taxa have been recorded, for example Eremazus cribratus Semenov, 1893 (Bezděk 2016b), Acrossus rufipes (Linnaeus, 1758), and Rhodaphodius foetens (Fabricius, 1787) (Dellacasa et al. 2016). These beetles are rather common in Kazakhstan, Kyrgyzstan, Turkmenistan, or Uzbekistan, and there are suitable similar habitats available for them in Tajikistan. Considering the numerous isolated and largely inaccessible biotopes, the presence of as many as 80 endemic species of Scarabaeoidea, and a remarkably few representatives of the subfamily Aphodiinae, it is very likely to expect some new taxa for the local fauna and perhaps even some yet undescribed. Already, this was confirmed by the recent discovery of three new species of Scarabaeoidea, Trochaloschema dubium, Lethrus ahriman, and L. asmodeus, as well as by the results of studies of other groups of beetles (Greń et al. 2016;Kadyrov et al. 2016) and aphids (Depa et al. 2017). Therefore, new expeditions to Tajikistan are highly desirable.