Semioscopis fareastenica Ponomarenko et Koshkin, 2025

Ponomarenko, Margarita G. & Koshkin, Evgeny S., 2025, New species of the spring flat moths of the genera Semioscopis Hübner and Luquetia Leraut (Lepidoptera: Depressariidae) from Far East of Russia with notes on related species, Zootaxa 5666 (4), pp. 529-549 : 533-537

Semioscopis fareastenica Ponomarenko et Koshkin sp. nov.

Figs 1–3 , 11–14 , 23–25 , 37–40 .

Semioscopis japonicella auct. (nec Saito, 1989): Lvovsky (1999: 59); Lvovsky & Dubatolov (2007: 56); Lvovsky (2016: 76, 2019: 53); Koo et al. (2023: 514) .

Type material. Holotype (red label with species name and authors): ♂, labeled: “ Russia, Khabarovskii Krai , Verkhnebureinskii district , Bureinskii Nature Reserve , Bureya River , 3 km SW of confluence of Levaya Bureya and Pravaya Bureya rivers, cordon “Strelka”, 51°38'39" N 134°15'45" E; 570 m a.s.l., 19.05.2021 (E.S. Koshkin leg.)”, GS 309 MP, FSCB.

Paratypes: Russia, Khabarovskii Krai: 1♀, same collecting data as for holotype (E.S. Koshkin leg.), GS 298 MP ; 1♂, 2♀♀; same locality and collector, 19.v 2016, GS 302 (♂) MP, 303 (♀) MP , 311 (♀) MP ; 1♂, Bikinskii district, 8 km SE Boitsovo village, upper reaches of Shivki river , vicinity of “Shivki” scientific station, 46°55'06" N 134°23'04" E, 165 m a.s.l., 24.iv 2021 (E.S. Koshkin leg.), GS 299 MP . Primorskii Krai: 1♀, Ussuriiskii district, “Suputinskii” [Ussuriiskii] Nature Reserve , 17.v 1948 (A.I. Kurentsov leg.), GS 310 MP ; 1♂, 1♀, Ussuriiskii district, 20 km SE Ussuriisk, Gornotajezhnoe village , 28.iv, 08.v 1995 (M.G. Ponomarenko leg.) ; 2♀♀, Shkotovskii district , 13 km E Novaya Moskva village, 43°20'32" N, 132°54'39" E; 420 m a.s.l., 28, 29.iv 2009 (M.G. Ponomarenko leg.), GS 297 MP , 304 MP; all in FSCB.

Diagnosis. The new species differs from all congeneric species by socius rectangular in shape and shorter than half width of tegumen in distal part, saccular process (cuiller) 2.2 times shorter than width of valva in place of its arising, aedeagus 7 times longer than cornutus and almost equal to valva in length, and by right digitiform process on anellus in the male genitalia.

Description. Adult ( Figs 1–2 , 11 ). Head with grey frons and vertex and dark-grey scales around eyes. Ocelli present. Antenna dark grey with scattered light-grey scales, with short cilia on ventral side in male; scape without pecten. Labial palpus with first segment 2 times shorter than second one, second segment 1.5 times longer than third one; first segment with alternating whitish and greyish-orange scales; second segment whitish in proximal part and brownish grey in distal part with white scales distally on outer side, and whitish on inner side; third segment whitish in proximal part and apically and dark brown in distal part on outer side, and light grey on inner side, darker distally. Ratio of eye diameter along anterior-posterior line and length of the labial palpus 1:4. Tegulae and thorax brownish grey. Forewing length 13.8–14.2 (♂), 10.7–13 (♀) mm, wingspan 29.2–30 (♂), 23–27.6 (♀). Forewing groundcolour pale beige with cross-hatching of short dark brownish and blackish strokes; pattern formed by longitudinal sinuous black thick streak from base of costa, which extending through part of cell, and a curved mark at end of cell; costal margin with blackish spot beyond middle and at 4/5 wing length; termen with 4–5 small blackish dots; brownish orange blurry and indistinct spots beyond discal cell and 4/5 wing length; fringe light grey, darker at base. Hindwing greyish beige; fringe light grey, darker at base. Forewing with Sc to costa beyond middle of wing length; R1–R5 to costa, R1, R2 and R3 separate at base, R4 and R5 stalked basally, diverging at distal third; M1–CuA1 to termen and CuA2 to tornus; M1– M3 free basally; CuA1 and CuA2 close basally, CuP reduced in basal part; 1A and 2A merged in distal 4/5 length. Hindwing with Sc to costa near 4/5 of wing length, Rs to costa before apex; M1–CuA1 to termen, M1 and M2 separate basally, M3 and CuA1 connate basally, CuA2 to tornus; A1–A3 separate basally, to dorsal margin.

Male genitalia ( Figs 12–14 , 23–25 ). Uncus almost equal to tegumen in length, with rounded notch on posterior margin, with rectangular socii. Gnathos with triangular lateral arms and rounded pineal median sclerite. Valva almost parallel-sided in basal 2/3, gradually narrowed towards rounded apex; saccular process (cuiller) slightly shorter than half width of valva in place of its arising, with pointed apex; saccular sclerotisation with narrowing at middle and significantly extended in distal part ( Figs 12 , 23 ). Anellus surrounding distal part of aedeagus, with right digitiform process on posterior margin ( Fig. 25 ); juxta with lateral setaceous lobe and wedge-shaped cut on each side of anterior part. Aedeagus almost equal to valva in length, cylindrical and blindly closed basally, curved at 2/5 length, with inflated basal 2/5 and truncated apex; cornutus 7 times shorter than aedeagus; opening for ejaculatory ductus shifted on left side of basal part ( Fig. 24 ).

Female genitalia ( Figs 37–40 ). Ovipositor short, membrane between 8 th and 9 th segments 2.6–3 times shorter than papillae analis; the latter sclerotised laterally. Apophysis posterioris 2.8 times longer than apophysis anterioris ( Fig. 37 ). Sternal part of segment 8 with trapezoidal notch on posterior margin and extended anterior margin, cup–shaped vaginal sinus with rounded ostium submerged under posterior edge of segment 7, ostium surrounded by granular area extended caudally ( Fig. 38 ). Antrum weakly sclerotised, with hard fold shortly beyond ostium and with thorned walls ( Figs 38, 39 ); ductus seminalis arising beyond antrum. Ductus bursae wrinkled, spirally twisted, slightly widened towards corpus bursae. Corpus bursae membranous, oval, with rhomboid gutter-shaped signum placed approximately at half of its length ( Fig. 40 ).

Distribution. Russia ( Far East: Khabarovskii Krai and Primorskii Krai), South Korea.

Etymology. The specific name is derived from the name of Far Eastern region, where it was discovered. Treated as a noun in the nominative singular standing in apposition to the generic name.

Remarks. The new species is most similar to S. japonicella Saito, 1989 and S. steinkellneriana ([Denis et Schiffermüller], 1775) in appearance by a longitudinal black sinuous streak on the proximal part of the forewing, which outlines the discal cell distally. The study of the holotype of S. japonicella allowed to clarify the differences in the appearance and the male genitalia between the type-specimen described from Japan and S. fareastenica sp. nov. The new species can be distinguished from S. japonicella by light grey forewing with thinner sinuous streak and semi-oval arc outlining discal cell, whereas S. japonicella has brownish forewing with relatively thick sinuous streak and semi-circle arc outlining discal cell ( Fig. 15 ). The most significant differences of the new species from S. japonicella in the male genitalia: saccular process (cuiller) shorter than width of valva in the place of its arising, socius rectangular in shape and less than half width of tegumen in distal part, aedeagus with distal part 2 times narrower than its basal part, cornutus 7 times shorter than total aedeagus length ( Figs 23–25 ). S. japonicella possesses a saccular process (cuiller) almost equal to width of valva in the place of its arising; socius trapezoidal and extended distally, longer than half width of tegumen in distal part; aedeagus slightly narrowed in distal part; cornutus 4 times shorter than total aedeagus length ( Figs 19–22 ). Main characters by which these two similar species can be distinguished are included in Table 2.

The similarity in appearance between S. japonicella and S. fareastenica sp. nov. actually contributed to the incorrect identification of the material from the south of the Russian Far East and South Korea as S. japonicella ( Lvovsky 1999; Koo et al. 2023). The illustrated male genitalia of the specimen from south of Russian Far East ( Lvovsky 1999: Fig. 19 , 6 ) are quite corresponding with those in the holotype of S. fareastenica sp. nov. and differ from the male genitalia of the holotype of S. japonicella by the characters listed above and in Table 2. The only specimen (female) from South Korea was found to be conspecific with S. fareastenica sp. nov. by the morphology of female genitalia ( Koo et al. 2023: Fig. 4 ). Besides, the genetic distance between the same sample from South Korea and the sample from southern Far East of Russia (Amurskaya Oblast’, Blagoveshchensk) is 0.2% on COI fragment ( Fig. 52 ), which also indicates that they belong to the same species. Since the samples from South Korea and Far East of Russia (Amurskaya Oblast’, Blagoveshchensk) posted to the GenBank (NCBI) and BOLD System databases were erroneously identified, their sequences in molecular analysis and in Table 1 are used under specific name in quotes S. “ japonicella ”.

character numbers in this table correspond to the numbers of the characters in circles in Figures 19–21, 23–25 .

Figures

FIGURE 52. Interspecific genetic distances in the genera Semioscopis and Luquetia.

FIGURES 1–10. Semioscopis spp. and Luquetia tigrina sp. nov., adults and heads with appendages. 1–3—Semioscopis fareastenica sp. nov., paratype male; 4, 5—S. strigulana; 6, 7—S. similis; 8–10—Luquetia tigrina sp. nov., holotype male. Figs 1, 4, 6, 8—adult; 2, 5, 7, 9—head with labial palpi, enlarged; 3, 10—flagellum with ciliation on ventral side, enlarged. Scale bar for figures 1, 4, 6, 8—2 mm.

FIGURES 11–18. Semioscopis fareastenica sp. nov. and S. japonicella Saito, adults and male genitalia, holotypes. 11–14—S. fareastenica sp. nov.: 11—adult, 12–14—male genitalia, GS 309, 12—ventral view, aedeagus removed; 13—aedeagus, lateral view; 14—uncus with socii in natural position in glycerin, enlarged; 15–18—S. japonicella Saito: 15—adult, 16—labels under holotype, 17—male genitalia, ventral view, aedeagus removed; 18—aedeagus, lateral view. Scale bar for figure 11—2 mm, figures 12–14—0.5 mm. Photographs 15–18 made by Dr. Yoshitsugu Nasu (Osaka Metropolitan University, Japan).

FIGURES 19–25. Semioscopis fareastenica sp. nov. and S. japonicella Saito, male genitalia, comparison of morphology. 19–22—S. japonicella Saito, holotype: 19, 21—male genitalia, ventral view, aedeagus removed; 20, 22—aedeagus, lateral view; 23–25—S. fareastenica sp. nov., paratype, GS 302: 23—male genitalia, ventral view, aedeagus removed; 24—aedeagus, lateral view; 25—juxta and lobes of transtilla in natural position in glycerin, enlarged. Scale bar—0.5 mm. The characters shown in Figs 19–25 under the numbers in circles correspond to the character numbers in Table 2. Photographs 19 and 20 made by Dr. Yoshitsugu Nasu (Osaka Metropolitan University, Japan), and drawings 21 and 22 are reproductions from the original description by Saito (1989).

FIGURES 37–43. Semioscopis fareastenica sp. nov. and Luquetia tigrina sp. nov., female genitalia. 37–40—Semioscopis fareastenica sp. nov., paratype, GS 303; 41–43—Luquetia tigrina sp. nov., paratype, GS 291. Figs 37, 41—ventral view; 38—ostial area (ostium, vaginal sinus, postvaginal plate, antrum); 39—inner side of antrum with thorns; 40, 43—signum; 42—ostial area (ostium, antevaginal and postvaginal plates, antrum). Figures 38–40, 42, 43 enlarged. Scale bar for figures 37 and 41—0.5 mm.