Sphegina (Asiosphegina) index Hippa, van Steenis & Mutin, 2015

Steenis, Jeroen Van, Hippa, Heikki & Mutin, Valeri A., 2018, Revision of the Oriental species of the genus Sphegina Meigen, 1822 (Diptera: Syrphidae), European Journal of Taxonomy 489, pp. 1-198 : 102-103

publication ID	https://doi.org/ 10.5852/ejt.2018.489
publication LSID	lsid:zoobank.org:pub:B234C53F-BB56-4F3D-B400-F214E19DCF90
DOI	https://doi.org/10.5281/zenodo.3850010
persistent identifier	https://treatment.plazi.org/id/03AF879D-1945-FF81-6BB9-A16D74FEFC21
treatment provided by	Valdenar
scientific name	Sphegina (Asiosphegina) index Hippa, van Steenis & Mutin, 2015
status

Treatment

Sphegina (Asiosphegina) index Hippa, van Steenis & Mutin, 2015 View in CoL

Figs 45B View Fig , 50B View Fig , 52B View Fig

Sphegina (Asiosphegina) index Hippa, van Steenis & Mutin, 2015: 19 View in CoL View Cited Treatment . Type locality: Kambaiti, Myanmar (holotype, ♂, NHRS).

Material examined

CHINA • 1 ♀; “Fukien, S. China / Shaowu: Tachulan / 1000 m. T. Maa ”; “ 25–30.IV.1943 ”; BPBM .

MYANMAR • 1 ♀; “ N.E. Burma / Kambaiti 7000 ft / 26–5–1934 [leg] Malaise”; “ Paratype ♀ / Sphegina (Asiosphegina) / malaisei Hippa , / van Steenis & Mutin, 2015 ” [red label]; JSA .

THAILAND • 1 ♀; “ Thailand , Chiang Mai / Doi Inthanon NP / checkpoint 2 1700 m / 18°31.559 ʹ N, 98°29.941 ʹ E / 26.X–2.XI.2006 Malaise trap / Y. Areeluck leg. T 383”; QSBG GoogleMaps • 1 ♀; “ Thailand , Chiang Mai / Doi Inthanon NP / summit marsh, 2500 m / 18°35.361 ʹ N, 98°29.157 ʹ E / 12.X–19.X.2006 Malaise Trap / Y. Areeluck leg. T 368”; JSA GoogleMaps .

VIETNAM • 1 ♂, 1 ♀; “NW VIETNAM: Tonkin / Hoang Lien N.P., 15 km, / W Sa Pa c. 1900 m / 15–21.X.1999 Malaise traps / [leg] C. v. Achterberg, RMNH ‘99”; NBC • 1 ♀; same data as for preceding; JSA • 1 ♀; “NW Vietnam ( Ton Kin ) / Sin Chay / 15–21.X.1999 / 1900 mtr. Mal. Trap / C. van Achterberg ”; JSA .

Description

Female

LENGTH. Body 6.0– 6.9 mm, wing 4.8–5.5 mm

HEAD. Face in lateral view concave, strongly projected antero-ventrally; frontal prominence weakly developed. Ratio width of vertex at anterior ocellus: width of head 1: 2.9–3.3; ratio width of ocellar triangle: width of vertex 1: 2.5–2.9; ratio length of ocellar triangle: length of frons 1: 2.8–3.2. Face black; grey pollinose, long pilose along eye-margin. Hypostomal bridge black, long pale pilose. Gena and mouth edge dark brown to black with large subtriangular non-pollinose shiny area. Frons and vertex black, slightly pollinose, a rectangular non-pollinose and shiny area posterior of lunula; pile short, light yellow. Frons with wide circular pit and wide furrow medially. Occiput black, light grey pollinose, light yellow pilose. Antenna dark brown with black setae dorsally on scape and pedicel; basoflagellomere long-oval, ratio width: length 1: 1.5–1.6; arista long pilose, about 2.5 times as long as basoflagellomere.

THORAX. Colour black, postpronotum light yellow; weakly grey pollinose, pleuron entirely more heavily grey pollinose; scutum and pleuron with very short adpressed light yellow pile. Scutellum subtriangular, black, shiny, only slightly pollinose, with pile slightly longer than on scutum, with two closely set, long setae medially at posterior margin, ratio length of scutellum: length of seta 1: 1.9–2.3.

WING. Entirely microtrichose; hyaline, stigma yellowish, crossveins brown infuscated. Crossvein dm-cu meeting vein M perpendicularly and vein M

meeting vein R

4+5

perpendicularly.

LEGS. Pro- and mesoleg yellow, tarsomeres 4 and 5 black. Metaleg, Fig. 52B View Fig , with coxa dark brown, trochanter yellow; femur black with basal ⅓ yellow, slightly incrassate and basally curved, with a long black seta anterodorsally near apex, ratio width: length 1: 5.0–5.4; tibia black and yellow biannulate, without apicoventral dens; tarsus entirely black, first tarsomere thin, ratio width: length 1: 3.2–3.4.

ABDOMEN. Length ratio of terga I: II: III: IV: V 1: 2.7–3.0: 2.3–2.6: 1.5–1.8: 0.6–0.7; ratio width at posterior margin: medial length of tergum II and III 1: 2.5–2.9 and 1: 0.8–0.9. Terga black, tergum II with anterior dark-orange fascia; tergum III with orange-yellow macula latero-medially; terga III and IV dark-orange; pile of terga short, light yellow; tergum I with one anterolateral strong black seta; sternum III rectangular, ratio width: length 1: 1.3–1.5; sternum IV rectangular, ratio width: length 1: 0.6–0.7 and sternum V squarish with convex posterior margin, width: length 1: 1.0–1.1.

Distribution and biology

Known from Myanmar, SE China, Thailand and Vietnam. A montane (1700–2500 m) species apparently with two flight periods: mid-May and from mid-October to early November. In Myanmar it was collected in a cloud forest with streams and swampy areas at an altitude of 2000 m. The specimen from Vietnam was collected in a Malaise trap near the Tram Ton Pass, the highest mountain pass in Vietnam (1900 m), near Fan Si Pan mountain. The Malaise trap had been set up in an area of montane forest disturbed by grazing buffaloes, containing muddy areas and small streams. Despite the cold and wet weather insects were rather abundantly flying (C. van Achterberg, pers. comm).

Remarks

The species was previously known only by the holotype from Myanmar, Kambaiti ( Hippa et al. 2015). One of the female paratypes of Sphegina (Asiosphegina) malaisei turned out to be the hitherto undescribed female of S. (A.) index . This particular specimen has very faintly infuscated wing and a slightly darkened ventral side of the metatrochanter giving a false impression of a carina.