Rhodostrophia crypta, a new species from Middle Asia (Lepidoptera: Geometridae)

Corresponding author: Jaan Viidalepp (vjaan@emu.ee), Igor Kostjuk (ikostjuk@univ.kiev.ua) Academic editor: Axel Hausmann Received: 25 Mar 2020 | Accepted: 27 Apr 2020 | Published: 13 May 2020 Citation: Viidalepp J, Kostjuk I (2020) Rhodostrophia crypta, a new species from Middle Asia (Lepidoptera: Geometridae). Biodiversity Data Journal 8: e52462. https://doi.org/10.3897/BDJ.8.e52462 ZooBank: urn:lsid:zoobank.org:pub:CB6381E3-1AD7-4407-B148-5C0B122832BF


Introduction
Hugo Christoph (Christoph 1877, Christoph 1885) collected a series of moths in the vicinity of Krasnovodsk (now Turkmenbashi) on the Turkmen shore of the Caspian Sea and supplemented his original description of Rhodostrophia vastaria Christoph, 1877 with line illustrations of a male and a female moth. Uvarov (1910) referred to R. vastaria from the South Urals.
Rhodostrophia vastaria was recorded as occurring in the territories of the Turkmen and Kazakh Soviet Republics in check lists by Viidalepp (1976), Viidalepp (1988) and Hausmann (2004), with a figure of male genitalia. However, a recent search for R. vastaria types in the collection of the ZISP, St. Petersburg has yielded information about two female specimens (Trusch and Hausmann 2007). New localities for R. vastaria in western Kazakhstan were listed by Gorbunov (2011). The species is repeatedly collected on the Ustjurt plateau, some hundreds of kilometres north of the type locality of R. vastaria.

Materials and methods
Materials from the collections of the Estonian University of Life Sciences, Tartu (the Institute of Zoology and Botany of Estonian Academy of Sciences -IZBE collection), the Zoological Museum of the Taras Shevchenko National University, Kyiv and the Zoologischer Staatssammlung München were studied.
New 'Rhodostrophia vastaria Christoph' records come from eastern Kazakhstan, specifically in the vicinity of Balkhash lake when the large lepidopterological collection of Dr A. Pototski was deposited in the IZBE insect collection. The distance between western collecting sites and new localities near Lake Balkhash is quite large. Authentic lectotype data for R. vastaria were published by Trusch and Hausmann (2007) and some material of Rhodostrophia vastaria for dissection was found in the Museum of Zoology of the Taras Shevchenko National University.
Digital images of the female lectotype of R. vastaria and the corresponding genitalia slide were studied, as well as digital images of R. vastaria moths and their genitalia slides from Ustjurt plateau (western Kazakhstan) from D. Shovkoon and a paper photo of a male from "Ili" in the collection of the Zoologisches Forschungsinstitut und Museum A. Koenig (Bonn).
Detailed comparison of moths from eastern and western populations of putative R. vastaria yields differences both in the external appearance of adults and in the build of their genitalia. In this study we describe the eastern Kazakh populations as a new species.

Taxon treatment
Rhodostrophia crypta, sp. n. Rhodostrophia vastaria and Rhodostrophia crypta, sp. n. are superficially similar but differing in characteristics of male and female genitalia, as discussed below.
Rhodostrophia crypta, sp. n. This new species is characterized with a wing span of 25-26 mm (Fig. 1a, b). The Uch-Aral male is grey with a conspicuous dark grey pattern and dusting (Fig. 1a); its hindwing postmedial line is outwardly dentate at the vein M3 and the forewing medial area seems relatively broader. West Kazakh moths (Fig. 1c, d) of R. vastaria are evenly sand-coloured, yellowish-grey and with sparse grey maculation. The sandy grey ground colour of the moths from the Balkhash region is more intensively covered by brown spots and the postmedial line is more suffused on hindwings (Fig. 1a, b).
The distal edge of the valva in the male genitalia is roundly bulged at the saccular corner in R. vastaria (Fig. 2a;Hausmann 2004: Fig. 174b), but it is straight in R. crypta, sp. n. (Fig. 2b). Female genitalia of moths are also different; moths of western population have the seventh segment of the abdomen and the tubular sclerotisation of the ductus bursae distinctly longer in moths of the western population (Fig. 3a) and the forked sclerite in the corpus bursae is also larger in western moths than in those moths from the eastern Kazakh population (Fig. 3b).
The differences in male and female genitalia structures and wing pattern between the western and eastern Kazakh populations justify the separation of the Balkhash lake shore populations as Rhodostrophia crypta Viidalepp & Kostjuk, sp. n.
Rhodostrophia jacularia (Hübner) has a very different, clear and contrasting wing pattern but similar male genitalia (with the distal margin of the valva smoothly rounded) and R. tabestana (Trusch and Hausmann 2007) has quite similar wings and colouration, but the distal margins of valvae are not straight; rather they are slightly concave. Genetically nearest species: Rhodostrophia jacularia (3.7%). The distally truncate shape of valva and the presence of a cornutus on the vesica in R. jacularia, R. crypta, sp. n., R. vastaria and R. tabestana allow them to be combined together in the Rhodostrophia jacularia species group. Distribution map of R. vastaria and R. crypta, sp. n.