Epistrophe aino (Matsumura, 1917)

Kim, Chan-Ouk, Hwang, Seul-Ma-Ro & Han, Hak-Seon Lee and Ho-Yeon, 2022, Ten species of the tribe Syrphini (Insecta: Diptera: Syrphidae) newly recorded in Korea, Journal of Species Research 11 (3), pp. 208-237 : 211-213

2. Epistrophe aino (Matsumura, 1917)

ƚǵÑHqỵỄOi (ljḑ) ( Figs. 1G- J , 4E- H )

Syrphus (Macrosyrphus) aino Matsumura and Adachi, 1917: 27 (type locality - Japan, Hokkaido, Sapporo; syntype 1♂, HUS; syntype 1♂, NIAES); Shiraki, 1930: 374 (redescription).

Epistrophe aino : Ninomiya, 1957: 188 (immature biology); Okuno, 1967: 126 (immature biology); Mutin and Barkalov, 1997: 185 (in review of Sakhalin and Kuril Islands syrphids); Mutin and Barakalov, 1999: 382 (in Russian Far East key); Rojo et al., 2003: 36 (in world aphidophagous syrphid revision); Ȏhara et al., 2014: 467 (in Japanese catalog); Mutin et al., 2016: 21 (in list of Tumnin river area, Russia); Barkalov and Mutin, 2018: 495 (in Russian checklist).

Diagnosis. Epistrophe aino can be distinguished from Korean congeners by the following combination of characteristics: 1) frons largely brownish yellow except for narrowly brownish-black posterior corner in males and posterior 3/4-4/ 5 in females ( Fig. 1G, I ); 2) lunule brownish yellow; 3) antenna largely brownish yellow except for variably darkened dorsal area of postpedicel ( Fig. 1H, J ); 4) wing-cell br almost bare; 5) abdominal sternites yellowish without any blackish markings except for male sternite 8 having large blackish spot; 6) basiphallus with 2 pairs of ventral processes ( Fig. 4 G-a, -b, H); 7) basiphallic apico-ventral processes relatively wide with serrated apex in ventral view ( Fig. 4 H-a); and 8) basiphallic baso-ventral processes with irregularly serrated posterior side in lateral view ( Fig. 4 G-b).

Description of Korean material. Male. Lengths and ratios: body length 8.9-11.5 mm; wing length 7.73-9.73 mm; head ratio 0.71-0.74; face ratio 0.43-0.45; eye ratio 0.52-0.57; gena-eye ratio 0.05-0.06; antenna-head ratio 0.39-0.43; postpedicel-pedicel ratio 1.78-2.00; arista-antenna ratio 1.03-1.18; wing ratio 3.56-3.63; wing-thorax ratio 2.23-2.42; vein M ratio 1.59-2.08; vein R 4+5 ratio 2.95-3.57. Head holoptic with eye contiguity slightly shorter than vertical triangle ( Fig. 1G ); compound eye dark brown with slight purplish tinge, bare; vertex black with slightly wavy brownish yellow and black hairs; frons largely brownish yellow except for narrowly brownish-black posterior corner, about posterior half with yellowish grey pruinosity, with variably mixed wavy brownish yellow and black hairs (usually brownish-yellow hairs more than black hairs); lunule brownish yellow, bare; antenna largely brownish yellow except for variably darkened dorsal area of postpedicel ( Fig. 1H ); face almost entirely brownish yellow ground color except for pair of small brownish-black lateral spots on lower facial margin ( Fig. 1 H-a), with greyish pruinosity, with wavy pale yellow hairs; facial knob rounded, almost bare; gena pale yellow to brownish yellow with greyish pruinosity, with pale yellow hairs ( Fig. 1H ). Thorax largely blackish with yellowish-grey pruinosity, with wavy brownish-yellow to pale yellow hairs ( Fig. 1G ); scutum with 4 wide longitudinal subshiny yellowish-grey pruinose stripes connected postero-marginally; medial scutual area between 2 inner yellowish grey stripes with pair of longitudinal greyish pruinose stripes (can be observed under appropriate lighting) interrupted at anterior 3/4; lateral margins of scutum matte yellow ( Fig. 1G, H ); scutellum brownish yellow, largely with wavy black hairs, but anterior to lateral side with wavy brownish-yellow hairs (sometimes brownish-yellow haired area larger than black haired area); pleura blackish, mostly with yellowish-grey pruinosity ( Fig. 1H ); anterior anepisternum, anterior 1/4-1/3 of posterior anepisternum, dorsomedial anepimeron, posterior anepimeron, meron, anatergite, mediotergite and metasternum bare; katepisternum with upper and lower wavy pale yellow hair patches, narrowly connected on posterior margin; halter with stem brownish yellow to pale yellow, knob pale yellow to yellow. Legs with coxae and trochanters basally brownish black, apically brownish yellow (sometimes almost entirely brownish yellow), with brownish-yellow hairs ( Fig. 1H ); femora brownish yellow with brownish-yellow hairs (hind femur apically mixed with short black hairs); fore and mid tibiae brownish yellow with short brownish-yellow hairs; hind tibia largely brownish yellow to pale brown, apically partially darkened, largely with short black hairs but apico-ventrally with short brownish-yellow hairs; fore and mid tarsi basally brownish yellow, apically pale brown to brown, with short brownish-yellow hairs (sometimes a few short black hairs sparsely mixed); hind tarsus dorsally brownish black to dark brown with short black hairs, ventrally pale brown to brown with short brownish-yellow hairs. Wing largely hyaline with slight pale brownish tinge ( Fig. 1G ); veins pale brown to brownish black; pterostigma pale brown; cell sc before pterostigma yellowish; wing membrane largely covered with microtrichiae except for basal bare areas (especially, cell br almost bare); upper and lower calypters pale yellow to brownish yellow with long brownish-yellow marginal hairs. Abdominal tergites unmargined, brownish-yellow ground color with black markings, with wavy brownish-yellow and black hairs (wave getting weaker towards apex) ( Fig. 1G ); tergite 1 largely brownish yellow except for subshiny black posterior margin (occasionally subshiny black area covering half or more area); tergite 2 with anteriorly widened black mid-stripe connected to narrow black transverse postero-marginal band; tergite 3 postero-marginally with narrow black transverse band, anetero-medially slightly protruded; tergite 4 with narrow black transverse subposterior band, antero-medially slightly protruded; terigte 5 entirely brownish yellow; sternites 1 and 2 pale yellow with wavy pale yellow hairs; sternites 3 and 4 pale yellow, largely with wavy pale yellow and short pale yellow hairs but posterior 1/3-1/2 mixed with short black hairs; sternite 5 brownish yellow to pale brown, anteriorly with brownish-yellow hairs, posteriorly with black hairs; sternites 6 and 7 pale brown to brown, largely with black hairs but anteriorly mixed with some brownish-yellow hairs; sternite 8 with rounded blackish spot of about 1/3-4/5 of sternite width, medially with black hairs, marginally with brownish-yellow hairs. Male genitalia ( Fig. 4E- H ) with epandrium slightly longer than height in lateral view ( Fig. 4F ); surstylus longer than width in caudal view (middle width about 2/3 of length when oriented to show broadest area) ( Fig. 4E ), slightly curved anteriorly with rounded apex in lateral view, basally with long brownish-yellow hairs, apically with short hairs ( Fig. 4F ); hypandrium with slightly up-curved lingula ( Fig. 4F ); lateral protuberance of hypandrium slightly longer than lingula, with widely rounded apex; distiphallus apically slightly widened in lateral view ( Fig. 4G ); about apico-ventral 2/5 of distiphallus densely with short spiny hairs; basiphallus with 2 pairs of ventral processes ( Fig. 4 G-a, -b, H); apico-ventral processes relatively wide, with serrated apex in ventral view ( Fig. 4 G-a, H-a); baso-ventral processes with irregularly serrated posterior side in lateral view ( Fig. 4 G-b). Female. Similar to male except for the following characteristics. Lengths and ratios: body length 10.2-11.8 mm; wing length 8.93- 9.60 mm; head ratio 0.70-0.74; face ratio 0.42-0.45; eye ratio 0.53-0.56; gena-eye ratio 0.04-0.07; antenna-head ratio 0.44-0.46; postpedicel-pedicel ratio 2.20- 2.27; arista-antenna ratio 1.02-1.08; wing ratio 3.39- 3.60; wing-thorax ratio 2.20-2.48; vein M ratio 1.53- 2.00; vein R 4+5 ratio 2.75-3.21. Head dichoptic with vertex about 0.15 × as wide as head in dorsal view ( Fig. 1I ); anterior 1/5-1/4 of frons brownish yellow, posterior 3/4-4/5 brownish black to black, with variably mixed brownish yellow and black hairs except for antero- and postero-marginal bare areas; frons heavily pruinose except for narrow median longitudinal and posterior 1/3 areas. Thorax ( Fig. 1I ): 4 wide longitudinal scutal pruinose stripes with more bluish tinge. Abdominal tergites: black mid stripe on tergite 2 distinctly narrow ( Fig. 1G vs. I); black bands on tergites 3 and 4 almost straight ( Fig. 1G vs. I).

Material examined. KOREA: Chungcheongbuk-do: Okcheon-gun, Gunbuk-myeon, Daechoeng Dam , N36° 21.363 ʹ E127° 35.33.7 ʹ, 31.V-2.VII.2005, P. Tripotin, 1 $; Daejeon-si: Daedeok-gu, Wa-dong , N36°24.02 ʹ E 127°25.98 ʹ, 17.IX-6.X.2006, P. Tripotin, 1 $; Gangwon-do: Donghae-si, Samhwa-dong , Mureung Valley , N37°28 ʹ 02 ʺ E129°01 ʹ 53 ʺ, 11.VI.2012, S.-W. Suk et al., 1♂ ( NIBR) ; Goseong-gun, Goseong-eup, Sottongnyeong , N38°18 ʹ 06 ʺ E126°21 ʹ 53 ʺ, 24.IX.2016, S.-S. Euo, C.- O. Kim, W.-R. Ha, 2♂ , 3$; Hongcheon-gun, Nae-myeon, Bangnae-ri , N37°51 ʹ 11 ʺ E128°16 ʹ 52 ʺ, 27.IX.2018, S.-S. Euo, C.-O. Kim, J.-H. Choi, 1 $; Hongcheon-gun, Nae-myeon, Gwangwon-ri , Woldoon-gol , N37°50 ʹ 52 ʺ E128°25 ʹ 24 ʺ, 16.VI.2018, S.-S. Euo, C.-O. Kim, J.-H. Choi, 4♂ ; ditto, 26.VII.2018, S.-S. Euo, C.-O. Kim, J.- H. Choi, 1♂ ; Inje-gun, Girin-myeon, Mt. Jeombongsan , from Jindong-ri to Gombaeryeong , N38°1 ʹ 40 ʺ E128° 25 ʹ 59 ʺ, 9.VII.2016, S.-S. Euo, C.-O. Kim, W.-R. Ha, 4♂ ; Wonju-si, Heungeop-myeon, Maeji-ri , Yonsei Univ. Mirae Campus , N37°17 ʹ 10 ʺ E127°54 ʹ 01 ʺ, 30.VI.2006, H.-W. Byun, J.-S. Lim, 1 $; ditto, 6.X.2016, S.-S. Euo, 2 $; ditto, 3.X.2017, S.-S. Euo, C.-O. Kim, 1♂ , 1$; ditto, 26.V.2018, S.-S. Euo, C.-O. Kim, J.-H. Choi, 1 $; ditto, 7.VI.2018, C.-O. Kim, J.-H. Choi, 1 $; ditto, 25. VI.2018, S.-S. Euo, 1 $; ditto, 29.VI.2018, S.-S. Euo, 1♂ , 2$; ditto, 30.VI.2018, S.-S. Euo, 1 $; ditto, 3.VII. 2018, S.-S. Euo, C.-O. Kim, J.-H. Choi, 1 $; Wonju-si, Panbu-myeon, Seogok-ri , Mt. Baegunsan , N37°14 ʹ 59 ʺ E127°57 ʹ 46 ʺ, 27.VI.2017, S.-S. Euo, C.-O. Kim, J.-H. Choi, 2♂ ; Gyeonggi-do: Gwacheon-si, Makgye-dong, Mt. Cheonggyesan , N37°24 ʹ 51 ʺ E127°02 ʹ 29 ʺ, 13.V. 2021, S.-S. Euo, C.-O. Kim, 1♂ ; Gyeongsangbuk-do: Pohang-si, Buk-gu, Heunghae-eup , Gokgang-ri , N36° 06 ʹ 51 ʺ E129°23 ʹ 37 ʺ, 4.VI.2011, S.-W. Suk et al., 1 $; Gyeongsangnam-do: Hamyang-gun, Hyucheon-myeon, Songjeon-ri , Mt. Jirisan , Munsusa Temple (400 m), N35° 24.739 ʹ E127°43.818 ʹ, 6-27.VI.2004, P. Tripotin, 2 $; ditto, 4-19.VI.2005, P. Tripotin, 1 $; Incheon-si: Gyeyang-gu, Gyesan-dong , Mt. Gyeyangsan , N37°32 ʹ 24 ʺ E126°41 ʹ 57 ʺ, 15.IX.2016, C.-O. Kim, 1♂ ; Jeollabuk-do: Sunchang-gun, Bokheung-myeon, Hwayang-ri , Mt. Hwagaesan , N35°27 ʹ 42 ʺ E128°54 ʹ 8 ʺ, 20.IX.2020, S.-S. Euo, C.-O. Kim, S.-P. Han, 1♂ ; ditto, 12.IX.2021, S.-S. Euo, C.-O. Kim, 3♂ . RUSSIA: Primorsky-Krai, Luk ̓ yanovka, lower Sukhodol River , N43°10.71 ʹ E132° 42.81 ʹ, 29-30.VIII.2002, K.-C. Holston, 1 $.

Distribution. Japan (Kuril Islands, Hokkaido, Honshu, Shikoku, Kyushu), Korea, Russian Far East.

Biology. Epistrophe aino is relatively common in Korea. Its flight period extends from May to October with a peak in June. To date, the following seven aphid species are recognized as its prey: Aphis medicaginis Koch, 1854 , Brevicoryne brassicae ( Linnaeus, 1758) , Hyalopterus pruni (Geoffroy, 1762) , Myzus persicae ( Sulzer, 1776) , Tuberocephalus sakurae (Matsumura, 1917) , and Uroleucon formosanum ( Takahashi, 1921) ( Ninomiya, 1957; Okuno, 1967).

Remarks. The examined Korean specimens agree well with the original description ( Matsumura and Adachi, 1917) and a syntype in HUS. The new Korean name of this species translates as “ Epistrophe fly having yellow abdomen” referring to its predominantly yellowish abdomen.

Figures

Fig. 1. A-F.Epistrophe aeka Kimura, 1989: (A, C) male body, dorsal and lateral view; (B) male abdomen, dorsal view (reconstructed from Fig. 1A); (D) male head, frontal view; (E, F) female body, dorsal and lateral view. G-J. Epistrophe aino (Matsumura, 1917): (G, H) male body, dorsal and lateral view; (I, J) female body, dorsal and lateral view. K-O. Epistrophe annulitarsis (Stackelberg, 1918): (K, M) male body, dorsal and lateral view; (L) male abdomen, ventral view;(N, O) female body, dorsal and lateral view. Voucher specimen codes:A-D - EpiAek_M1; E, F - EpiAek_F1; G, H - EpiAin_M4; I, J - EpiAin_F2; K, M - EpiAnn_M2; L - EpiAnn_M3; N, O - EpiAnn_F1.

Fig. 4. Male genitalia. A-D. Epistrophe aeka Kimura, 1989: (A) caudal view; (B) lateral view; (C) aedeagus, lateral view; (D) basiphallic ventral processes, ventral view. E-H. Epistrophe aino (Matsumura, 1917):(E) caudal view; (F) lateral view; (G) aedeagus, lateral view; (H) basiphallic ventral processes, ventral view. I-L. Epistrophe annulitarsis (Stackelberg, 1918):(I) caudal view; (J) lateral view;(K) aedeagus, lateral view; (L) basiphallic ventral processes, ventral view. Scale bars: 0.3 mm. Voucher specimen codes: A-D - EpiAek_F1; E-H - Epi- Ain_M5; I-L - EpiAnn_M3.