Species of Orthosia Ochsenheimer, 1816 and Anorthoa Berio, 1980 genera (Lepidoptera, Noctuidae) in Western Transbaikalia

We report for the first-time occurrence of three species from the genus Orthosia – O. ariuna Hrebl., O. askoldensis Stgr.; O. ella Butl., and a species Anorthoa munda Den. et Schiff on the territory of Western Transbaikalia. The faunas of these spring species are similar between Western and Eastern Transbaikalia (70%) and close to the fauna of the Far East (50%).


Introduction
Orthosia Ochs. is a large (more than 80 species) Holarctic genus of lepidopterans (Lepidoptera) from the Noctuidae family. The majority of the genus inhabits a temperate zone of Eastern and South-Eastern Asia [1,2]. It is divided into several subgenera. Recently, one of them (Anorthoa Berio) was recognized as a separate genus [3]. In Eurasia, Orthosia species are primarily localized in the coastal ocean areas. The majority of species live in rainforests. In the Far East, they live in broadleaved, cedar-broadleaved, and mixed forests [1]. Another particular feature of these insects is early adult activity: the second part of April and May. In Transbaikalia, it is observed in the first decade of June in cold years. Few specimens of the second generation of O. gothica L. can be active at the end of July -the beginning of August. In Russia, there are 22 species of Orthosia genus and only 2 species of Anorthoa genus. Fourteen of them are spread in the Far East [4,5] [5][6][7][8][9] were found in the whole region of Transbaikalia. In Western Transbaikalia, were known only 3 last species. We aimed to study faunas of Orthosia and Anorthoa inhabiting Western Transbaikalia in more detail.

Materials and Methods
The material of the Lepidoptera genus stored in the collection of the Laboratory of Ecology and Systematics of Animals (LESA) of the Institute of General and Experimental Biology SB RAS was examined. The field surveys were conducted in April-May 2012-2021 in forests of the southern coast of Lake Baikal, Ulan-Burgasy Mountain range, and the Selenga Midmountain area. Specimens were collected with standard sweep nets and ultraviolet lamps, including light traps. The insects were placed on cotton pads or in entomological boxes. Before 2000, the material used in the study was primarily collected by T V Vlasova (Gordeeva). After 2000 and up to date, the material has been collected by S Yu Gordeev. The reference list for insect findings below contains only the names of other collectors. The species identification of insects was conducted according to [1,3,10], for which the genitalia preparations were made with binocular Stemi 2000-C equipped with a video-ocular AxioCam ERc 5s. These preparations were stored in Eppendorf vials filled with glycerin together with specimens. The species were classified according to the system accepted in recent publications [2,5]. The comparison of the Orthosia faunas was based on species lists from the 'Catalogue of the Lepidoptera of Russia' [5] and our data. The analysis of the similarities in the compared faunas was made with BIODIV software. Of all the similarity measure indexes, the Kulczynski index was the most representative [11] because it gives more weight to shared characters maintaining the total number of characters. The clusters were established with the method of Unweighted Pair Group Average.
Small-leaved woods with pines near grass meadows.

Results
The following abbreviations are used: m -male; f -female (figure 1). In the northern part of the Selenga Midmountain area, this species is the most common Metaheterocera of early spring [13]. It was observed within the steppe, forest-steppe, and taiga belts. Earlier, a single female specimen was found in Buryatia in the Barguzin basin [9]. The image of the female genitalia, taken by T V Gordeeva, is stored in the records of LESA. Revision of the material showed that this species is frequently observed in the northern part of the Selenga Midmountain area (Ulan-Ude, Onokhoy settlement). One specimen was found in the wet forests of the Ulan-Burgasy Mountain range. This Euro-Siberian species may access the valleys of the rivers Selenga and Uda via this area.
6. Orthosia ella (Butler, 1878) Material: Bolshaya Rechka, May 1-2, 2019, 1m. The species is found in the Far East and the Eastern Transbaikal. It is systemically close to the Euro-Siberian species O. gracilis and hardly distinguishable from it by appearance. However, there are evident differences in the anatomy of the male and female genitalia [3]. The habitat in the eastern part of Europe needs to be verified [3]. In the region, it was known no further than the eastern part of the South-Eastern Transbaikal Region [6]. It should be noted that during the study period, this species was not found once in the northern part of the Selenga Midmountain area.
7. Anorthoa munda ((Denis & Schiffermüller), 1775) Material: Bolshaya Rechka, May 1-2, 2019, 10mm, 1f. Eurasian species that is not found in some regions of Eastern Siberia. This is the first time it is observed in the Transbaikal Region. Some moths were collected on the southern-western Baikal coast near the Bolshaya Rechka settlement.  Regions are numbered according to the 'Catalogue of the Lepidoptera of Russia' [5].