Sphegina (Asiosphegina) pusilla, 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 : 53-54

Sphegina (Asiosphegina) pusilla sp. n.

Figs 33 A–D

MALE. Body length 4.9–5.5 mm, wing length 4.2–4.6 mm. Head. Face strongly concave and weakly projected antero-ventrally; frontal prominence very weakly developed (similar to Fig. 1E). Width of vertex at anterior ocellus:width of head 1:4.3; depth of occipital concavity ca. 1/6 of the width of an eye in dorsal view. Width of face:width of head 1:4.8. Face dark brown, pale pollinose. Gena shiny brown. Frons and vertex black, lunula brownish; frontal prominence shiny dark brown, the more posterior parts densely pale pollinose, behind frontal prominence with diffused fascia of denser pollinosity; the pile short, erect and pale. Occiput dull black. Eye with a large area of enlarged facets at anterior margin. Antenna with scapus and pedicellus yellow or brownish, basoflagellomere darker brown, oval; arista nonpilose. Thorax. Colour black, faintly pale pollinose, the pile pale, short, almost invisible on dorsal parts; scutellum semicircular, shiny, a pair of thin, short, pale setae at apical margin. Wing. Hyaline, stigma brownish. Legs. Pro- and mesoleg yellow, tarsomeres 4 and 5 black. Metaleg: coxa brown; trochanter simple, yellow; femur yellow, the apex 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 1:4.1:2.0:1.4. Tergites shiny brown, tergite III with a yellow subanterior fascia, its width about 1/3 of the tergite length, the pile of tergites pale, short, adpressed, with some brown pile on posterior 1/2 of tergite; tergite I with an oblique row of 3–4 pale setae laterally; sternite IV ( Fig. 33 A) brownish, the posterior part paler yellowish, the pile pale; sternites VI–VIII black, the pile short and pale. Genitalia, Figs 33 B–D. Note the slightly modified cercus and the asymmetrical surstyli. The superior lobes are symmetrical. Sternite IX is asymmetrical. FEMALE. Unknown.

Type material. HOLOTYPE. ♂, N.E. Burma, Kambaiti, 7000 ft, 14.v.1934, R. Malaise ( SMNH). PARATYPE. 1♂ with same data as holotype, also labeled Sphegina asciiformis Brun , det. v. Doesburg ( NBC).

Etymology. The name is Latin, pusilla , very little, referring to the small size of the fly.

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

Figures

FIGURE 33. Sphegina (Asiosphegina) pusilla sp. n. (holotype). A. Posterior part of sternite IV, ventral view. B. Genitalia, lateral view. C. Right surstylus, lateral view. D. Left surstylus, lateral view. Scale 0.5 mm.