Revision of the family Metarbelidae (Lepidoptera) of the Oriental Region. IX. Description of Marcopoloia svetlanae sp. n. from the Central Thailand Author Yakovlev, Roman V. Altai State University, Lenina pr. 61, Barnaul, 656049, Russia. E-mail: yakovlev _ asu @ mail. ru & Tomsk State University, Lenina pr. 36, 634050, Tomsk, Russia. Author Korshunov, Alexey V. Museum-Reserve " Tomskaya Pisanitsa ", Tomskaya 5 a, Kemerovo, 650099 Russia. Author Zolotuhin, Vadim V. Ulyanovsk State Pedagogical University, pl. 100 - letia Lenina 4, 432700, Ulyanovsk, Russia. text Ecologica Montenegrina 2022 2022-04-23 53 35 37 http://dx.doi.org/10.37828/em.2022.53.4 journal article 10.37828/em.2022.53.4 2336-9744 13240898 urn:lsid:zoobank.org:pub:477FED07-9635-4E38-AC75-3C6284923576 Marcopoloia svetlanae Yakovlev & Korshunov , sp. n. http://zoobank.org/ urn:lsid:zoobank.org:act: 50F6EA10-4780-483B-9201-3F490223B9AD Figs 1−4 Material . Holotype (male), Thailand , Nachon Ratchasima Province , Nong Bun Mak District , near Nong Bunnak village , N 14º40′51.8′′ , E 102º27′08.3′′ , leaf- falling gallery forest, 9−25.iii.2020 , leg. A. Korshunov ( ZISP ). 1 males , 2 females ( paratypes ), same locality and data ( RYB ). Figures 1−4. Marcopoloia svetlanae Yakovlev & Korshunov , sp. n. adult specimens and genitalia : 1. Male, holotype (ZISP); 2. Male genitalia (holotype); 3. Female, paratype (RYB); 4. Female genitalia (paratype). Description . Male ( Fig. 1 ). Length of fore wing 9−10 mm ( holotype – 9 mm ). Antenna short (slightly shorter than half of fore wing in length), bipectinate, setae twice longer than antenna rod diameter. Fore wing brown with poorly noticeable blurred pattern, marginal area and fringe mottled (brown at veins, ocher between veins). Hind wing light-grey, anal area light-brown, marginal area and fringe mottled (brown at veins, ocher between veins). Male genitalia ( Fig. 2 ). Uncus relatively long, slightly extended apically, with deep semi-oval notch on top; subscaphium long, funnel-like, significantly extended in medium third; gnathos arms thin, long; gnathos lamellar; valve short semicircular, with bundle of long setae on transtilla, saccular margin sclerotized, curved in distal third, small mastoid harpe on outer margin of valve; juxta ring-shaped, small; saccus poorly expressed; phallus very short with strongly extended coecum, robust finger-like cornutus in vesica. Female ( Fig. 3 ). Length of fore wing 11−13 mm . Antenna short (slightly shorter than half of fore wing in length), bipectinate, setae equal to antenna rod diameter. Fore wing grey-brown, with reticulated pattern, round grey spot with light-brown rim at top of discal cell, marginal area and fringe mottled (brown at veins, ocher between veins). Hind wing grey, fringe grey unicolorous. Female genitalia ( Fig. 4 ). Ovipositor very short, papillae anales lobe-like, wide, anterior apophyses very short, twice shorter than posterior apophyses, ostium cup-like, ductus basally sclerotized, distally membranous, bursa shaped as elongated bag. Diagnosis . The new species clearly differs from the known species of the genus in the reduced pattern on the male fore wing. In the male genital structure, it mostly resembles M. thaica Yakovlev & Zolotuhin, 2021 , from which it differs in the very deep semi-oval notch on the uncus apically (in M. thaica the apical notch on the uncus is small, semicircular), in the poorly curved saccular margin of the valve (in M. thaica the saccular margin is more curved throughout its length) and in the poorly developed harpe on the outer margin of the valve (in M. thaica the harpe is significantly larger ). Habitat and flight period . Collected by light in leaf-falling gallery forest, flight period – March. Etymology . The new species is named after Svetlana Oplachko ( Kemerovo , Russia ), the wife of the second author of this message.