Aberrasine ryabinini Koshkin, 2025

Aberrasine ryabinini Koshkin View in CoL sp. nov.

urn:lsid:zoobank.org:act:8442D22A-F5E2-47E9-A642-36DFE852CCB5

( Figs 1A–D View FIGURE 1 , 2A View FIGURE 2 , 3A View FIGURE 3 )

Type material. Holotype ( Figs 1A, B View FIGURE 1 , 2A View FIGURE 2 ): ♂, Vietnam, Kon Tum Province, 9 km NW Mang Den, Ngoc Le Mount , 14°37’55” N, 108°12’57” E, 1550 m, 11–12.IV.2024, leg. Evgeny S. Koshkin (ex EKC, will be deposited in ZISP). GoogleMaps

Paratypes ( Figs 1C, D View FIGURE 1 , 3A View FIGURE 3 ): 2 ♀, same data as holotype ( EKC, ZISP). GoogleMaps

Diagnosis. Aberrasine ryabinini is easily distinguished from all its congeners by the following combination of external features: contrasting yellow veins on forewings and hindwings, the absence of a discal spot, and an almost straight medial line parallel to the outer margin on the forewing. In the male genitalia, the new species is characterized by a sharply separated wide distal part of the valva with several toothed processes of irregular size on the costa. Vesica of Aberrasine ryabinini sp. n. bear a single cluster of cornuti, while all other Aberrasine species have two. Externally, the new species resembles Aberrasine atuntseensis ( Daniel, 1951) in the shape of the antemedial and medial lines and in the absence of a discal spot on the forewing. However, unlike A. ryabinini sp. n., A. atuntseensis is larger, the costal margin of its forewing is dark, and the postmedial line continues from the costa to the CuA2 vein (in A. ryabinini sp. n. it reaches the inner margin of the wing); all veins from the postmedial line to the outer margin are black, and in the rest of the forewing and on the hindwing the veins are not yellow ( Daniel 1951; Fang 2000). A faint yellow color appears along limited sections of some veins in several specimens of A. aberrans ( Butler, 1877) , but is not nearly as well developed as in A. ryabinini sp. n., in which all veins are strongly outlined in yellow. All other Aberrasine species lack the yellow contrasting coloration of the veins. The discal spot on the forewing, except A. ryabinini sp. n. and A. atuntseensis , is absent also in several other Aberrasine species: A. variata , A. shiou , A. dingjiai , all three species of the strigivenata group. At the same time, these species are clearly distinguished from A. ryabinini sp. n. by other external characters. A straight medial line with a similar slope (so that it is almost parallel to the outer margin of the forewing), except A. ryabinini sp. n. and A. atuntseensis , is also present in three species of the strigivenata group ( A. strigivenata ( Hampson, 1894) , A. pangsau N. Singh, Kirti & Bisht, 2021 and A. tiani S.-Y. Huang, Volynkin, N. Singh & M. Wang, 2021 ).At the same time, other elements of the wing pattern are practically absent in the above-mentioned species. The female genitalia of A. ryabinini sp. n. are most similar to those of A. aberrans , differing in a wider ostium bursae, a shorter ductus bursae, a larger appendix bursae with a more extensive area covered with spinules, and a less strongly concave posterior margin of the 7th sternite than in A. aberrans .

Description. Adult. Male ( Figs 1A, B View FIGURE 1 ). Wingspan 24.5 mm. Forewing length 12.5 mm. Head. Antennae yellowish, weakly ciliate. Labial palps yellowish, short. Proboscis short, short, slender, light brown. Head and frons yellow. Eyes rounded, brown. Thorax. Thorax yellow-orange with two rounded black spots dorsally; patagium unicolor orange-yellow; tegula orange with black spot. Legs unicolorous, yellowish. Forewing narrow, costa medially curved; ground color orange-red; veins yellow; transverse antemedial, medial and postmedial lines black; basal dot black; subbasal area with two elongated black spots; antemedial line curved at right angle in upper third; medial line straight, slightly curved at inner margin of forewing; antemedial and medial lines join at right angles near forewing costa; postmedial line strongly zigzagging; subterminal area with black streaks along veins; discal spot absent. Hindwing pale pink with pale yellow veins. Cilia on fore and hind wings yellow. Underside of forewing pinkish with slightly translucent dark pattern ( Fig. 1B View FIGURE 1 ). Underside of hindwing pinkish with yellowish costa and veins. Abdomen. Abdomen paler than thorax, yellow, terminal segments with long dark hairs. Female ( Figs 1C, D View FIGURE 1 ) similar to male, but antennae filiform, forewing costa not curved, antemedial and medial lines not joined. Abdomen pale yellow without long dark hairs. Wingspan 23–24.5 mm. Forewing length 12–13 mm.

Male genitalia ( Fig. 2A View FIGURE 2 ). Uncus long, slender, pointed; tegumen short and broad; vinculum broad; saccus broad, rounded; costa with rounded protrusion medially; distal part of costa differentiated by a deep notch and bearing several toothed processes of irregular size; apical process large, spine-like; distal part of valva wide, with membranous lobe; distal saccular process long, pointed; phallus straight, short and thick. Vesica about size of phallus, sack-shaped, with two subbasal short, rounded diverticula and one cluster of tooth-like cornuti; series of cornuti beginning as a wide area of 7–8 rows of cornuti, continuing to distal end as a long sinuous band 1–2 cornuti thick, with a slight widening in the middle; base of vesica ejaculatorius with crescentic sclerotized plate. Female genitalia ( Fig. 3A View FIGURE 3 ). Papillae anales broad, rectangular with rounded edges; apophyses anteriores and posteriores long and thin, about equal in length; 7th sternite wide, its posterior margin slightly concave; ostium bursae wide; ductus bursae wide and short; corpus bursae oval, densely covered with spinules, which are small in basal half of corpus bursae and larger in its distal part; appendix bursae large and long, strongly curved inwards, densely covered with large spinules on inner side.

Ecology. Aberrasine ryabinini sp. n. was collected in a slightly disturbed mountain deciduous forest at an altitude of 1550 m ( Fig. 4 View FIGURE 4 ). The new species occurs sympatrically with another species of the genus, A. peraffinis ( Fang, 1991) , which is found at the foot of Mount Ngoc Le at an altitude of about 1000 to 1100 m.

Distribution. Currently, Aberrasine ryabinini sp. n. is only known from Ngoc Le Mount in the northern part of the Central Highlands region (Kon Tum Province, Central Vietnam).

Etymology. The new species is dedicated to the memory of Prof. Dr. Nikolay Andreevich Ryabinin (1946– 2023), a famous Russian soil zoologist, my teacher and friend.