Sphegina (Asiosphegina) sinesmila, 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 : 49-50

Sphegina (Asiosphegina) sinesmila sp. n.

Figs 30 A–C

MALE. Body length 4.6 mm, wing length 3.8 mm. Head. Face moderately concave and very weakly projected antero-ventrally; frontal prominence very weakly developed (somewhat similar to Fig. 1E). Width of vertex at anterior ocellus:width of head 1:3.7; the depth of occipital concavity ca. 1/8 of the width of an eye in dorsal view. Width of face:width of head 1:4.2. Face black, pale pollinose. Gena shiny brown. Frons and vertex black, lunula shiny brown, frontal prominence shiny, more posterior parts pollinose, the erect pile short and pale. Occiput dull black. Eye with a large area of enlarged facets at anterior margin. Antenna brown; basoflagellomere dark brown, oval; arista nonpilose. Thorax. Colour dull black or partly brown laterally, pale pollinose, the pile scattered, short, adpressed and pale; scutellum semicircular, shiny, with a pair of very short, shorter than scutellum, thin, pale setae at posterior margin. Wing. Hyaline, stigma yellow. Legs. Pro- and mesoleg yellow, tarsomeres 4 and 5 black. Metaleg: coxa brown; trochanter simple, yellow; femur brown, the basal 1/5 yellowish and a broad annulus on the apical 1/2 yellow; tibia without apico-ventral tooth, brownish, the basal 1/4 and an annulus on the apical 1/2 yellow; tarsus dark brown or black. Abdomen. Length ratio of tergites I, II, III and IV 1:3.0:1.8:1.6. Tergites shiny black; tergite III with a yellow anterior fascia as wide as 1/2 of tergite length, the pile of tergites pale, short, adpressed, becoming longer towards the lateral margin; tergite I with an oblique row of 3–4 pale setae laterally; sternite IV ( Fig. 30 C) brown, with short pale pile; sternite VI ( Fig. 30 C) without a tubercle at posterior margin, black, the pile erect, pale; sternites VII and VIII simple, black, the pile short and pale. Genitalia, Figs 30 A, B. Note the slightly asymmetrical surstyli and the very large strongly asymmetrical cerci. The superior lobes are symmetrical. FEMALE. Unknown.

Type material. HOLOTYPE. ♂, N.E. Burma, Kambaiti, 2000 m, 24.v.1934, R. Malaise ( SMNH). PARATYPE. 1♂ with same data as holotype except 25.v. ( NBC).

Etymology. The name is composed of the Latin words -sine, without, and smila, carving-knife, referring to the lack of the knife-like lobe on the male tergite IV, which is possessed by the other similar species.

Discussion. Sphegina sinesmila is similar to S. cultrigera , S. ensifera and S. siculifera . It differs from the latter three by lacking a long sword-like lobe postero-laterally on the left side of the male sternite IV and by lacking a small short finger-like lobe at posterior margin of sternite VI. All these species can probably be distinguished by the colour of tergite III as mentioned in the key. The genitalia resemble those of S. ensifera but differ by having the cerci more asymmetric, surstylus narrower and the subtriangular sublobe at the ventral margin of the superior lobe being more anterior in position. S. sinesmila is also greatly similar to S. minuta , S. parvula and S. pusilla , to an extent that they may be very difficult to distinguish without reference to male genitalia (table 1). Thirty females belonging to these species have been left unnamed because of these difficulties. For further discussion, see under S. parvula .

Figures

FIGURE 30. Sphegina (Asiosphegina) sinesmila sp. n. (holotype). A. Genitalia, lateral view; aedeagus and left side cercus marked with broken line. B. Left side surstylus. C. Posterior part of abdomen, ventral view. Scale 0.5 mm.