Udea tritalis (Christoph, 1881)

(Figs. 1N, 4G, 4H)

Botys tritalis Christoph, 1881: 20. TL: Russia, Primorsky Kraj, Vladivostok.

Udea tritalis: Nuss et al., 2003 –2021.

Material examined. 1 male, Is. Ulleungdo, GB: Ulleung, 2018.07.08. (Kim SS).

Diagnosis. Udea tritalis can be diagnosed by the dark grayish forewing with the large snow-man shaped discal dot on the broad central fascia and the grayish hindwing with the dark subtermen. Udea tritalis is externally similar to U. lugubralis (Leech, 1889) in wing pattern elements but can be distinguished by the smaller wingspan, the blackish wings, and the waved subterminal line of the forewing.

Description. Wingspan 22mm.Antennae filiform; frons broad, dark brown; maxillary palpi minute; labial palpi long in length, about three times to eye diameter, dark brown. Body white. Forewing dark gray in ground color; basal part tinged with dark grayish; antemedial line blackish, slanted, medially strongly incurved; postmedial line blackish, undulating; central fascia broad, tapered from middle to dorsum, a long black snow-man shaped discal dot; subtermen dark gray; subtermen lined with blackish; fringe dark gray. Hindwing grayish in ground color; antemedian with a dark brown lunular short line; subtermen dark grayish. Male genitalia. Uncus mushroom-shaped with thin slender base and hairy apex; gnathos small rounded process; juxta broad; saccus broad, rounded. Valva long, slender, hairy; costa long, sclerotized, basally thicker, distally tapered; fibula straight, slender process; sacculus weakly sclerotized, basally bent, distally narrowed. Aedeagus long, slender, cornuti long sclerotized plate with a pair of dentate processes.

Distribution. South Korea, Japan, Russian Far East, and northern China.

DNA barcoding. One specimen from South Korea (OK501208) was sequenced, and the genetic difference between U. tritalis and its relative, U. fulvalis (Hübner) was 15.6%.

Remarks. The genus Udea, one of the species-rich groups of the Crambidae, comprises 214 species worldwide and the tribe can be diagnosed by the several synapomorphies: the depth of gap of juxta is 10%–60% of the dorsoventral length of juxta, the strongly sclerotized colliculum anterior of the antrum, the elongate rhombical to ovate signum (Mally et al., 2019). In South Korea, nine species of Udea are recorded including U. tritalis.