Sphegina (Asiosphegina) minuta, Hippa, Heikki, Steenis, Jeroen Van & Mutin, Valeri A., 2015

Hippa, Heikki, Steenis, Jeroen Van & Mutin, Valeri A., 2015, The genus Sphegina Meigen (Diptera, Syrphidae) in a biodiversity hotspot: the thirty-six sympatric species in Kambaiti, Myanmar, Zootaxa 3954 (1), pp. 1-67 : 52-53

Sphegina (Asiosphegina) minuta sp. n.

Figs 3 C, 32A–C

MALE. Body length 4.8–5.2 mm, wing length 4.0– 4.5 mm. Head. Face strongly concave, weakly projected antero-ventrally; frontal prominence very weakly developed (similar to Fig. 1E). Width of vertex at anterior ocellus:width of head 1:3.6; the depth of occipital concavity ca. 1/6 of the width of an eye in dorsal view. Width of face:width of head 1:4.2. Face black entirely or brownish ventrally, pale pollinose. Gena shiny brown or brownish (in pale specimens). Frons and vertex dull black, lunula shiny brownish, frontal prominence shiny brown, posterior part of frons with pale pollinosity which is diminishing towards vertex; the pile very short, erect and pale. Occiput dull black. Eye with a large area of enlarged facets at anterior margin. Antenna entirely brown or scapus and pedicellus paler than the basoflagellomere; basoflagellomere oval; arista nonpilose. Thorax. Colour black, faintly pale pollinose, the pile very short, adpressed and pale; scutellum semicircular, shiny, at apical margin a pair of thin convergent, pale, setae which are shorter than scutellum. Wing. Hyaline, stigma yellow. Legs. Pro- and mesoleg yellow, tarsomeres 4 and 5 black. Metaleg ( Fig. 3 C): coxa brown; trochanter simple, yellow; femur yellow, the apical 1/5–1/6 and a wide annulus on the basal 1/2 brown; tibia without apico-ventral tooth, yellowish, the apical part and an annulus on the basal 1/2 brown; tarsus dark brown. Abdomen. Length ratio of tergites I, II, III and IV 1:3.7:2.0:1.7. Tergites shiny black, tergite III with a yellow subanterior fascia nearly 1/2 as wide as tergite length, the pile of tergites short, adpressed and pale, becoming longer towards the lateral margin; tergite I laterally with an oblique row of 3–4 pale setae; sternite IV ( Fig. 32 C) brown, the pile pale; sternites VI–VIII black, the pile short and pale. Genitalia, Figs 32 A, B. Note the asymmetrical surstyli and the enlarged cercus. The superior lobes are symmetrical. Sternite IX is slightly asymmetrical ventrally. FEMALE. Unknown.

Type material. HOLOTYPE. ♂, N.E. Burma, Kambaiti, 2000 m, 19.iv.1934, R. Malaise ( SMNH). PARATYPES. 2♂ with same data as holotype except 7000 ft., 15.iv. ( SMNH, NBC); 2♂ with same data except 7000 ft., 14. v. and Sphegina asciiformis Brun , det. v. Doesburg ( SMNH, NBC).

Etymology. The name is Latin, minuta , small, referring to the small size of the fly.

Discussion. Sphegina minuta is similar to S. parvula and S. pusilla , and by lesser extent also to S. sinesmila . For further discussion, see under S. parvula above.

Sphegina tenuis Brunetti, 1915 is similar to other small species like S. minuta and S. pusilla by hyaline wings, yellow pro- and mesolegs with two black apical tarsomeres and subbasal pale fascia on tergite III. It differs from these species by having mesonotum with three infuscated vittae and metafemur pale basally and dark apically.

Figures

FIGURE 3. Metaleg, prolateral view (A, D female, B, C, E male). A. Sphegina (Asiosphegina) bilobata sp. n. (paratype). B. S. (A.) forceps sp. n. (paratype). C. S. (A.) minuta sp. n. (paratype). D. S. (A.) gigas sp. n. (paratype). E. S. (A.) carinata sp. n. (paratype). Scale 1.0 mm.

FIGURE 32. Sphegina (Asiosphegina) minuta sp. n. (holotype). A. Genitalia, lateral view. B. Left surstylus, lateral view. C. Posterior part of sternite IV, ventral view. Scale 0.5 mm.