Synanthedon bastak O. Gorbunov et Koshkin, 2023

Gorbunov, O. G. & Koshkin, E. S., 2023, A new species of the genus Synanthedon Hübner, 1819 (Lepidoptera: Sesiidae) from the Russian Far East, Far Eastern Entomologist 473, pp. 20-28 : 21-27

Synanthedon bastak O. Gorbunov et Koshkin , sp. n.

https://zoobank.org/NomenclaturalActs/ 137B7B8D-CE39-4992-A91F-1C5BCB2A374E

Figs 1, 2 , 7–11

MATERIAL. Holotype – ♂ ( Figs 1, 2 ) with labels: “ Russia / Jewish Autonomous Oblast /

Obluchenskii district / Bastak Nature Reserve / cordon “39th km” 49°05ʹ25ʺ N, / 133°05ʹ21ʺ E, 150 m / willow thickets along stream / 11.06.2022, leg. E.S. Koshkin ”; “ in trap with pheromone of / Synanthedon flaviventris / (produced by Pherobank BV, / Netherlands) / time of catch 14.00–16.00”; “ SESIIDAE / Pictures No. / 0005-0006–2023 / Photo by O. Gorbunov ”; “ HOLOTYPUS ♂ / Synanthedon bastak / O. Gorbunov et Koshkin, 2023 / O. Gorbunov des., 2022”. Paratypes: 3 ♂♂, with same locality as in holotype, 11.06.2022, 12.06.2022 and 13.06.2022, leg. E.S. Koshkin ( SESIIDAE / Pictures No. / 0007-0010–2023), 1 ♂ with genitalia preparation No. OG–001-2023 .

DESCRIPTION. Male (holotype) ( Figs 1–2 ). Alar expanse 20.5 mm; body length 11.2 mm; forewing 9.4 mm; antenna 6.1 mm.

Head: antenna and scapus black with dark blue shine; frons dark gray-brown with anthracitic shine medially and greenish-blue shine laterally; labial palpus black with purple-blue shine exterior-dorsally and yellow interior-ventrally; vertex and pericephalic hairs black with bright anthracitic shine; neck plate black with greenish-blue shine.

Thorax dorsally entirely black with bright greenish-violet shine; thorax laterally black with bright violet shine and large yellow-orange spot medially; both metepimeron and metameron posteriorly black with dark violet shine densely covered with black, long, hair-like scales.

Legs: fore coxa dark brown to black with bright violet shine and few pale yellow scales exterior-distally; fore femur dark brown to black with bronze-violet shine and a few pale yellow scales interior-distally; fore tibia dorsally dark brown to black with bronze shine, ventrally whitish with golden shine; fore tarsus dorsally dark grey-brown with golden shine, ventrally whitish with golden shine; mid coxa dark brown to black with greenish-violet shine; mid femur dark brown to black with blue-violet shine; mid tibia dark brown to black with greenish-violet shine; spurs whitish with oily shine; mid tarsus dorsally dark grey-brown with bronze shine and small yellowish spot distally on basal tarsomere, ventrally whitish with oily shine; hind coxa dark brown to black with greenish-violet shine; hind femur dark brown to black with blue-violet shine; hind tibia dark brown to black with greenish-violet shine; spurs whitish with oily shine; hind tarsus dorsally dark grey-brown with bronze-violet shine on basal tarsomere and bronze shine on remaining tarsomeres, ventrally yellowish with golden shine.

Forewing dorsally with basal part black with bright greenish-violet shine; costal and anal margins, CuA-stem, veins within external transparent area and apical area black with blue-violet shine; discal spot trapeziform, black with dark greenish shine; ventrally costal and anal margins, CuA-stem and surface between veins R 3 and CuA 1 within apical area yellow; discal spot, stripe between veins R 1 – R 3 and veins distally of discal spot dark brown to black with dark purple-violet shine; cilia dark brown with bronze shine; transparent areas well-developed, densely covered with translucent scales with light golden hue; posterior transparent area reaching distal margin of discal spot; external transparent area large, rounded distally, divided into five cells between veins R 3 and CuA 1, level to vein M 2 about 2.2 times as broad as discal spot and 1.1 times ad broad as apical area; cilia dark brown with bronze shine.

Hindwing transparent; dorsally costal margin, discal spot, veins and outer margin black with purple-violet shine; ventrally costal margin yellow, discal spot, veins and outer margin dark brown to black with bronze-purple shine; cilia dark brown with bronze shine, anally yellow; discal spot triangular, not reaching base of common stem M 3 –CuA 1; outer margin narrow, about 0.5 times as broad as cilia.

Abdomen black with dark greenish-violet shine; laterally segments 1 and 2 narrowly yellow-orange; segment 4 with broad, slightly narrower dorsally, yellow-orange ring; anal tuft well-developed, black with dark greenish shine dorsally and blue-violet shine ventrally.

MALE GENITALIA (paratype, genital preparation № OG–001-2023) ( Figs 7–11 ). Tegumen-uncus complex relatively broad; scopula androconialis well-developed, about 0.5 times as long as tegumen-uncus complex ( Fig. 7 ); crista gnathi medialis long and broad; crista gnati lateralis subcordiform, short and slightly broader than crista gnathi medialis ( Fig. 7 ); valva ( Fig. 8 ) trapeziform, crista sacculi oblique, long, about 0.44 as long as length of valva, pocketshaped, covered with two rows of strong flat-topped setae; saccus ( Fig. 9 ) narrow, flatted basally, short, about 0.5 times as long as vinculum; phallus ( Fig. 10 ) rather thin, straight, slightly broadened subdistally, about 0.7 times as long as valva, with short finger-shaped projection and few strong thorns subdistally; vesica with numerous small cornuti ( Fig. 11 ).

FEMALE. Unknown.

INDIVIDUAL VARIABILITY. The specimens slightly varying in the number of yellow-orange scales on the thorax laterally and abdomen. Individual size is variable as follows: wings span 17.0– 20.5 mm; body length 10.0– 11.2 mm; forewing 7.8–9.4 mm; antenna 5.8– 6.1 mm.

DIFFERENTIAL DIAGNOSIS. Without a doubt, this new species belongs to the Synanthedon andrenaeformis (Laspeyres, 1801) species-group and is very close to S. soffneri Špatenka, 1983 (type locality: “ Bohemia mer., Šumava (Böhmerwald), Dobrá na Šumavě, …” ( Špatenka, 1983: 30)). These two species can be distinguished by the size of the external transparent area of the forewing (small, rounded distally, divided into five cells between veins R 3 and CuA1, level to vein M 2 about 1.75 times as broad as discal spot and about 0.75 times as broad as apical area in S. soffneri , vs. large, rounded distally, divided into five cells between veins R 3 and CuA 1, level to vein M 2 about 2.2 times as broad as discal spot and 1.1 times as broad as apical area in the new species; cp. Figs 1–2 with Figs 3–4 ), number of yellow scales on the forewing ventrally (visibly more numerous in S. bastak sp. n.; compare Figs 1–2 with Figs 3–4 ), and by some details in the male genitalia (crista gnathi lateralis subcordiform, short and slightly broader than crista gnathi medialis; crista sacculi long, about 0.44 as long as length of valva, covered with two rows of strong flat-topped setae; saccus narrow, flatted basally, short, about 0.5 times as long as vinculum; phallus rather thin, straight, slightly broadened subdistally, with short finger-shaped projection and few strong thorns subdistally in S. bastak sp. n., vs. crista gnathi lateralis subcordiform, short and visibly shorter than crista gnathi medialis; crista sacculi, long, about 0.41 as long as length of valva, covered with more numerous strong flat-topped setae; saccus broad, rounded basally, short, about 0.4 times as long as vinculum; phallus rather thick, straight, slightly broadened subdistally, with short, toothed, finger-shaped projection and numerous strong thorns subdistally in S. soffneri ; compare Figs 7–11 with Figs 12–16 ).

S. bastak sp. n. is separable from S. spatenkai O. Gorbunov, 1991 (type locality: “… USSR, Transcaucasus, Georgia, Meskhetian Mt. Range, appr. 6 km S Abastumani, 41°42’N, 42°50’E,” ( Gorbunov, 1991: 125)) by the colouration of the labial palpus (black with greenish-violet shine in S. spatenkai , vs. black with purple-blue shine exterior-dorsally and yellow interior-ventrally in S. bastak sp. n.; compare Fig. 2 with Fig. 6 ), forewing ventrally (surface between veins R 3 and CuA 1 within apical area dark brown to black with violet shine in S. spatenkai , vs. surface between veins R 3 and CuA 1 within apical area yellow in the new species; compare Fig. 2 with Fig. 6 ) and abdomen (dorsally black with bright greenish shine, laterally segments 1 and 2 without yellow-orange scales in the species compared, vs. black with dark greenish-violet shine, laterally segments 1 and 2 narrowly yellow-orange in S. bastak sp. n.), and by somewhat different size and shape of the discal spot of the forewing; compare Figs 1–2 with Figs 5–6 ). In addition, these two species differ from each other by some details in the male genitalia (compare Figs 7–11 with figs 1–4 in Gorbunov, 1991: 127).

From all other so-called “red banded” far eastern species of the genus, namely S. culiciformis (Linnaeus, 1758) (type locality: “Europe [ Sweden].” ( Špatenka et al., 1999: 125), S. velox (Fixsen, 1887) (type locality: “ Korea, Pung-Tung.” ( Špatenka et al., 1999: 131) = South Korea, Gangwon-do, Cheorwon-gun) and S. herzi Špatenka et O. Gorbunov, 1992 (type locality: “ Insel Sakhalin, Bezirk Anivsk, Novoalexandrovsk, …” ( Špatenka & Gorbunov, 1992: 378)) is distinguished by a combination of the colour signs of various parts of the body and by the structure of the male genitalia (compare Figs 1–2 , 7–11 with corresponding figures in Špatenka et al., 1999; Gorbunov & Tschistjakov, 1999; Arita et al., 2004; Gorbunov, 2022).

BIONOMICS AND HABITAT. All specimens were collected in a roadside borrow pit and a nearby swampy stream floodplain, where shrubs of Salix sp. , trees of Betula pendula subsp. mandshurica (Regel) Ashburner et McAll. and Alnus hirsuta (Spach) Rupr. grow mainly. On the adjacent territory there is a coniferous-broadleaved forest with predominance of Quercus mongolica Fisch. ex Turcz. , Tilia spp. , Betula costata Trautv. , Populus tremula L. and Pinus koraiensis Siebold et Zucc. The larval host plant is unknown, but the morphological similarity to S. soffneri suggests that they may be species of the genus Lonicera L., of which there are four in the type locality of this new species, namely L. chrysantha Turcz. ex Ledeb. , L. caeruleae L., L. maximowiczii (Rupr.) Regel , and L. ruprechtiana Regel. Specimens of the type series were collected in the first half of June using an artificial sex attractant for European populations of Synanthedon flaviventris (Staudinger, 1883) . They were attracted from 14:00 to 16:00.

DISTRIBUTION. The new species is known only from the type locality in the northeastern part of the Jewish Autonomous Oblast in the Russian Far East .

ETHYMOLOGY. This new species is named after the Bastak Nature Reserve, where it was collected.

For help in organizing and conducting expedition research, we are grateful to the team of the Bastak Reserve , namely director Dr. Alexander Y. Kalinin, deputy director for research Dr. Tamara A. Rubtsova, senior researcher Ekaterina S. Lonkina and staff of the department for the protection of the reserve area. We are indebted to Dr. Anatoly V. Krupitsky (Moscow, Russia) for carefully checking the English of an advanced draft .

The study was conducted using the equipment of the Joint Usage Center “Instrumental methods in ecology” at the A.N. Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences (Moscow, Russia). The investigation was fulfilled within the State research projects No. АААА-А18-118042490060 - 1 (OG) and No. 121021500060-4 (EK) .

Figures

Figs 1–6. Synanthedon spp. 1–2 – S. bastak O. Gorbunov et Koshkin, sp. n., holotype ♂, Sesiidae picture No. 0005-0006–2023; alar expanse 20.5 mm; 3–4 – S. soffneri Špatenka, 1983, Russia: Moscow Region, Serebryano-Prudsky District, Lishnyagi, 54°23.89ʹ N, 038°32.15ʹ E, 172 m, 08.VI.2021, O. Gorbunov leg., picture No. 0243-0244–2021; alar expanse 19.7 mm; 5–6 – S. spatenkai O. Gorbunov, 1991, holotype ♂, Sesiidae picture No. 0011-0012–2023; alar expanse 19.4 mm. 1, 3, 5 – dorsal view; 2, 4, 6 – ventral view.

Figs 7–11. Male genitalia of Synanthedon bastak O. Gorbunov et Koshkin, sp. n., paratype, genitalia preparation No. OG–001-2023. 7 – tegumen-uncus complex; 8 – valva; 9 – saccus; 10 – phallus; 11 – phallus distally. Scale bar: 0.5 mm and 0.2 mm for 11.

Figs 12–16. Male genitalia of Synanthedon soffneri Špatenka, 1983, Russia; Moscow Region, Serebryano-Prudsky District, Lishnyagi, 54°23.89ʹ N, 038°32.15ʹ E, 172 m, 08.VI.2021, O. Gorbunov leg., genitalia preparation No. OG–001-2023. 12 – tegumen-uncus complex; 13 – valva; 14 – saccus; 15 – phallus; 16 – phallus distally. Scale bar: 0.5 mm, and 0.2 mm for 16.