On the taxonomy of the genus Eugoa Walker, 1858, with descriptions of two new species from Laos and Vietnam (Lepidoptera, Erebidae, Arctiinae, Lithosiini) Author Volynkin, Anton V. Altai State University, Lenina str. 61, RF- 656049, Barnaul, Russia. E-mails: volynkin _ a @ mail. ru, barsine @ yahoo. com & Tomsk State University, Institute of Biology, Ecology, Soil Science, Agriculture and Forestry, Lenina Avenue, 36, RF 634050, Tomsk, Russia & Corresponding author Author Bucsek, Karol Slovak Academy of Sciences, Institute of Zoology, Dúbravská cesta 9, Bratislava 845 06 Slovak Republic. E-mail: monosyntaxis @ gmail. com Author Černý, Karel Tiergartenstrasse 27, A- 6020 Innsbruck, Austria. E-mail: natura. cerny @ aon. at Author Saldaitis, Aidas Nature Research Centre, Akademijos str., 2, LT- 08412, Vilnius- 21, Lithuania. E-mail: saldrasa @ gmail. com text Ecologica Montenegrina 2018 2018-11-20 19 102 109 http://dx.doi.org/10.37828/em.2018.19.11 journal article 10.37828/em.2018.19.11 2336-9744 13360118 urn:lsid:zoobank.org:pub:41E9BB8A-A7CB-4839-86A5-D495A07C8BD8 Eugoa sinxayi Volynkin, Bucsek & Černý , sp. nov. ( Figs 4 , 10 ) Type material examined . Holotype ( Figs 4 , 10 ): male, “ Nam Phao , 620 m , Bolikhamxai prov. , Laos . Date : August 9, 2010 . Collect : Kenichiro Nakao, No. 100809232”, slide slide AV 4097m (Coll. MWM / ZSM ). Diagnosis . Eugoa sinxayi sp. nov. is a sister species of E. dubatolovi sp. nov. Externally the two species are very similar ( Figs 1–4 ), only pattern elements of E. sinxayi sp. nov. seem to be slightly paler, brown. The main differences between these species can be found in the male genitalia structures: in E. sinxayi sp. nov. ( Fig. 10 ) the uncus is narrower basally than that of E. dubatolovi sp. nov. ( Figs 7–9 ), the penicular lobes are shorter, with more smoothly curved margins, the juxta is longer, the basal lobe of sacculus distally narrower and rounded, the apex of valva is slightly longer, apically dentate, the subbasal lateral diverticulum is much broader, the medial lateral diverticulum is broader and weaker granulated, the medial ventral diverticulum is much longer, the apical diverticulum is narrower. Description . Adult ( Fig. 4 ). Forewing length 12 mm . Male antennae bipectinate. Head and thorax dark brown; tegula with large blackish spot; abdomen ochreous brown. Ground color of forewing pale grayish brown, with strong dark brown suffusion. Pattern dark brown. Two diffuse blackish dots in cell; basal line interrupted into broad costal spot and thin, trigonal medial stroke; antemedial line as two large spots; postmedial line S-like curved, strongly broadened at costa and anal margin; subterminal line thin, diffuse, broken; terminal line as row of dots between veins; cilia pale brown, with row of dark dots between veins. Hindwing pale brown with grayish suffusion; cilia pale brown. Male genitalia ( Fig. 10 ). Uncus spearheadlike, dorso-ventrally flattened; scaphium narrow, weakly sclerotized, subscaphium weakly setose; tegumen short, penicular lobes medium-broad, smoothly rounded; juxta large, trapezoidal, apically elongated, with small apical medial concavity; vinculum very short, U-like. Valva elongated, distally slightly narrowed and dorsally curved; broad row of strong hair-like setae in medial area of valva; apex of valva heavily sclerotized, broad, apically dentate; subapical ventral process of valva trigonal, directed ventrally; sacculus broad, its basal lobe large, broad, apically rounded, setose, extends beyond costal margin. Aedeagus medium-long, proximally broadened, slightly curved distally; vesica broad, membranous, with membranous, broad and round subbasal ventral diverticulum, granulated, long, broadly conical medial ventral diverticulum, granulated, round medial lateral diverticulum, and membranous, finger-like apical diverticulum; row of five thorn-like cornuti of different size medio-laterally; vesica ejaculatorius directed dorsally. Female unknown. Figures 7–10. Eugoa spp. : male genitalia. 7, E. dubatolovi , holotype, S Laos, slide AV3112m; 8, E. dubatolovi , paratype, S Vietnam, slide AV3105m; 9, E. dubatolovi , paratype, S Vietnam, slide AV4098m; 10, E. sinxayi , holotype, C Laos, slide AV4098m. Distribution. The species is known only from Central Laos . Etymology . „Sinxay‟ is a hero, a character of the Lao epic poem „Sang Sinxay‟.