Volucella thompsoni, Choi & Ôhara & Han, 2006

Choi, Deuk-Soo, Ôhara, Kenji & Han, Ho-Yeon, 2006, Taxonomic notes on the Volucella pellucens species group (Diptera: Syrphidae) with a description of one new species from the Eastern Palaearctic, Zootaxa 1185, pp. 1-19 : 4-8

Volucella thompsoni n.sp. ( Figs. 1A–I , 5A–D )

Volucella matsumurai Han et Choi, 2001: 125 , 206 (as new name of V. pellucens var. japonica Matsumura, 1916 ), misidentification (see Remarks of V. pellucens tabanoides ).

Diagnosis

This species can be readily distinguished from other members of the Volucella pellucens group by its longer abdominal tergite 2 (longer than tergite 3, or at most 2.4x wider than long; Figs. 5A, C ). Males can be further differentiated by their basoflagellomeres in lateral view slightly constricted in middle ( Fig. 1C ) and the surstyli greatly shortened in lateral view ( Figs. 1G, H ).

Description

Measurements and Ratios. Body length 11–16mm; wing length 11–13.8mm; antennal length 0.92–1.26mm; wing­mesonotum ratio 2.46–2.89; eye ratio 0.51–0.59; eye contiguity­vertex ratio 0.44–0.59; eye contiguity­frons ratio 0.4–0.57; basoflagellomere ratio 2–2.57; vein R 4+5 ratio 0.26–0.3; vein M ratio 0.48–0.56; fore tibia­basotarsomere ratio 2.25–2.6; 2nd tergite ratio 2–2.39; 2nd tergite­scutellum ratio 1.64–1.95.

Male. Head ( Figs. 1A–C ) yellow brown ground color with dark brown to black vertical triangle, post­ocular orbit, posteroventral portion of face, and gena; face yellow brown pilose with varying size of black macula posteroventrally; ventral portion of face distinctly protrude with more or less pointed apex; gena shiny black with short yellow setulae; lunule shiny yellow brown; frons yellow brown with black and yellow setulae mixed; eyes holoptic, dense pilose; antenna almost entirely yellow brown with black setulae; basoflagellomere 2.1–2.6x longer than wide, slightly constricted in middle. Thorax ( Figs. 5A, B ) with black setae and dense black to yellow brown setulae; 4–6 notopleurals, 4–5 supra­alars, 4–5 postalars; 4–6 prescutellars; 4–7 marginal scutellars; 3–5 anepisternals; scutum smooth, shiny black with brown to dark brown lateral margins; postpronotum pale yellow with yellow brown setulae; notopleuron smooth, shiny dark brown with yellow brown and black setulae mixed; scutellum smooth, shiny brown densely with short black setulae; pleural and sternal sclerites short pubescent; anterior anepisternum black with long yellow brown setulae; posterior anepisternum black with yellow brown and black setulae mixed; katepisternum black, mostly with long black setulae; anterior anepimeron shiny black with long black setulae; posterior anepimeron brownish black without any setulae; katepimeron brown to dark brown with yellow setulae; meron dark brown with few setulae posteriorly; metasternum black with long black setulae ventrally; katatergite dark brown with black setulae; anatergite dark brown without setulae. Wing ( Fig. 5A ) hyaline with broad discal and anterior apical dark brown maculae; narrow areas along veins M 1, dm­cu, CuA 1, and CuA 2 dark brown; wing surface microtrichose except for bare areas in anterior half of cell BM and anal lobe, and anterior 2/3 of cell CuP; 3–7 setulae along vein RS; calypter pale yellow, short pubescent with long plumose marginal hairs, lengths of hairs vary but longest one about 1/3 as long as halter; halter pale to yellow brown. Legs almost entirely black except basal 1/3–1/2 of fore and midtibiae dark brown; densely covered with black setulae. Abdomen ( Figs. 5A, B ) 1.3–1.7x longer than wide; tergite 1 shiny dark brown with yellow brown setulae; tergite 2 ivory white medially with narrow yellow brown longitudinal stripe, densely with pale setulae; tergites 3 and 4 shiny black with black setulae; sternite 1 black with yellow brown setulae; sternite 2 ivory white with pale setulae; sternite 3 anteriorly ivory white and posteriorly black; sternite 4 black with black setulae. Genitalia ( Figs. 1G–I ) dark brown in ground color; epandrium roughly square in lateral view; cercus yellow brown with yellow brown setulae, short, truncated in lateral view, surstylus greatly reduced with sharp posteromedial projection in lateral view, posterodorsally with inward directed 3–4 black teeth; hypandrium ventrally with whitish membrane; superior lobe basally with small triangular membranous area, single hook­like, curved downward; aedeagus pale yellow, largely membranous, and apically swollen.

Female. Similar to male except for: frons almost entirely yellow brown; eyes ( Figs. 1D–F ) dichoptic; basoflagellomere transversely elliptic (1.9–2.3x longer than wide) without medial constriction; scutum with more extensive brownish portion than in male ( Figs. 5A vs. C).

Type materials

Holotype Male , KOREA: Gangwon­do : Wonju­si : Panbu­myeon, Mt. Baegunsan, 28.VI.2000, D.­S. Choi & S.­K. Kim . Paratypes: KOREA: Chungcheongbuk­do: Jecheonsi: Songgye­ri, Jeolgol , 29. VI.1997, H.­Y. Han et al., 1♂, 2♀ , Chungcheongnam­do: Boryeong­si: Cheongna­myeon, Mt. Oseosan , 20.VII.1999, H.­Y. Han et al., 1♀ , Gangwon­do: Wonju­si: Heungeop­myeon , Yonsei Univ. Campus , 3.VIII.1999, D.­S. Choi, 1♀ ; ditto, 16.VII.2003, H.­W. Byun, 1♀ ; ditto, 22. VI.2004, H.­W. Byun, 1♀ ; ditto, 5.VII.2004, D.­S. Choi et al., 3♀ ; Panbu­myeon, Mt. Baegunsan , 21.VII.1998, D.­S. Choi & S.­K. Kim, 1♂ , Yeongwol­gun: Yeongwol­eup, Mt. Taehwasan , 9. VI.2001, D.­S. Choi & S.­K. Kim, 1♂ , Gyeonggi­do: Seongnam­si: Namhansanseong , 17.VIII.1993, S.­J. Park, 1♀ , Yangpyeong­gun: Yongmun­myeon, Mt. Yongmunsan , 30.VII.1998, H.­W. Byun et al., 1♀ , Gyeongsangbuk­do: Yeongju­si: Sunheung­myeon, Mt. Sobaeksan , 11. VI.2004, H.­W. Byun et al., 1♂ , Gyeongsangnam­do: Goseong­gun: Yeonghyeon­myeon, Bongrimri , 21. VI.1987, 1♀ , Hamyang­gun: Macheon­myeon, Mt. Jirisan , Chilson Valley (706m), Malaise trap (70% EtOH), 27. VI –23.VII.2001, D.­S. Ku, 1♀ ; Yeohang­myeon , 31. V.1987, 1♀ , Sancheong­gun: Samjang­myeon, Naewonsa , 13.VII.1990, D.­S. Ku, 2♀ , Ulju­gun: Samnam­myeon, Mt. Yeongchuksan , 29. VI.2003, H.­Y. Han et al., 1♀ , Ulsan: Sangbukmyeon, Mt. Gajisan , 23. VI.1987, 1♀ ; ditto, 24. VI.1987, J.­K. Kim, 1♀ ; ditto, 27. VI.1989, K.­S. Kim, 1♀ ; ditto, 1.VII.1990, J.­E. Park, 1♀ ; ditto, S.­S. Kim, 1♀ , Jeollabuk­do: Mujugun: Sangbuk­myeon, Mt. Deogyusan , 24.VII.1999, K.­H. Kang, 1♀ . JAPAN: Hokkaido: Kushiro, Lake Mashu (N. crater rim, Akan Nat. Park ), 23–24.VII.1980, FC Thompson, 1♂ ( USNM) ; Zenibako, Otaru , 20.VII.1965, T. Kocha, 1♂ ( HUS) , Zenibako, Otaru , 20.VII.1965, T. Kocha, 1♂ ( HUS) ; Mitsumata, Kamishihoro, Tokachi , 21.VIII.1993, K. Kuromoto, 1♂, 1♀ ( TPMT) ; Obihiro , 14.VIII.1995, H. Inoue, 1♀ ( OUHJ) ; Koibuku Riv., Hidaka , 16.VII.1962, 1♀ ( OUHJ) ; Hokkaido Univ. Exp. Forest, Tomakomai , 19.VIII.1977, K. Ôhara, 3♀ ( TPMT) ; ditto, M. Suwa, 1♀ ( TPMT) ; Ohnuma, Oshima , 30.VIII.1977, M. Yamamoto, 1♀ ( TPMT) , Honshu: Mt. Hayachine , Iwate Pref., 26.VII.1975, K. Tsuruta, 1♂ ( TPMT) ; Renge Spa, Niigata Pref., 29.VII.1977, K. Baba, 1♀ ( TPMT) ; Japon: Chunzenji ( Nikko , Tochigi Pref.,), 22. –7–15, Edme Gallois ( HUS), Uenohara, Minakami, Gunma Pref., 10.VIII.1987, N. Tamaki, 1♀ ( TPMT) ; Kiso­Ontake , Nagano Pref., 30.VII.1994, H. Ohishi, 2♀ ( TPMT) ; Mt. Tateshinayama , Nagano Pref., 1.VII.1971, R. & F. Ishikawa, 1♂ ( NSMT) ; Mt. Nyukasayama , Nagano Pref., 13.VII.1980, N. Koda, 1♂ ( TPMT) ; Mt. Mitsu­toge , Yamanashi Pref., 31.VII.1981, Y. Kurosawa, 1♀ ( NSMT) ; Gozaishi , Nirasaki, Yamanashi Pref., 3.VIII.1992, H. Ohishi, 2♀ ( TPMT) ; Daibosatu , Enzan, Yamanashi Pref., 19.VIII.1991, H. Ohishi, 1♀ ( TPMT) ; Hirkura , Mie Pref., 9. VI.1991, H. Ohishi, 2♂ ( TPMT) ; Sugi­toge , Kyoto City, Kyoto Pref., 25.VII.1992, H. Ohishi, 1♀ ( TPMT) ; Seryo , Kyoto Pref., 12.VIII.1937, T. Kimura, 1♀ ( TPMT) ; Kitayama Riv. , Okutama­dani, Nara Pref., 26. VI.1994, Keitaro Harusawa, 1♀ ( TPMT) , Shikoku: Mt. Takashiro­yama , Kisawa, Tokushima Pref., 17–18.VII.1994, Kiyoshi Masaki, 1♂, 1♀ ( TPMT) . Except for the Japanese paratypes (depositories shown in parenthesis), all the other type specimens including the holotype are deposited in YSUW.

Distribution

Korea, Japan.

Biology

Unknown.

Etymology

This species is named after Dr. F. Christian Thompson who contributed a great deal for the systematics of Syrphidae . He initially suggested the study of Volucella to the first author.

Remarks

We have occasionally found this species mixed with V. pellucens tabanoides specimens under same identification labels in the Korean institutions. These two species superficially resemble each other, but the new species is easily separable by the longer abdominal tergite 2 in both sexes, and much darker vertex in female. Further examination of the male genitalia strongly suggests that this species might not even be closely related to V. pellucens . The male genitalic structures (especially the highly reduced surstyli; Figs. 1G, H ) are so unique that we were not able to associate the new species with any other Volucella species. We are currently investigating this matter using both morphological and molecular data (Choi et al., in prep.). Our preliminary analysis based on mitochondrial 16S rRNA and COII gene sequences suggests that V. thompsoni n.sp. might be more closely related to V. nigropicta (the zonaria species group) than the other species of the pellucens species group.

Figures

FIGURE 1. Volucella thompsoni n.sp. A–C, male head in anterior, dorsal, and lateral view; D–F, female head in anterior, dorsal, and lateral view; G, male genitalia, lateral view; H, surstylus, inner view; I, male genitalia, posterodorsal view.

FIGURE 5. Volucella species (dorsal and lateral view). A–D, V. thompsoni n.sp. (A, B, male, C, D, female); E–H, V.inflata (E, F, male, G, H, female); I–L, V. nigricans (I, J, male, K, L, female); M–P, V. pellucens pellucens (M, N, male, O, P, female); Q–T, V. pellucens tabanoides (Q, R, male, S, T, female).