Sphegina (Asiosphegina) pollinosa, 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 : 59-60

Sphegina (Asiosphegina) pollinosa sp. n.

Figs 38 A–D

MALE. Body length 4.5–5.5 mm, wing length 4.5–5.3 mm. Head. Face very weakly concave, weakly projected antero-ventrally; frontal prominence weakly developed (somewhat similar to Fig. 1F). Width of vertex at anterior ocellus:width of head 1:3.5; depth of occipital fossa ca. 1/6 of the width of an eye in dorsal view. Width of face:width of head 1:4.5. Face dark brown, densely pale pollinose. Gena weakly shiny yellow or brownish. Frons and vertex black, densely pale pollinose; lunula shiny brownish, the pile short, erect and pale; frons with a low medial pit posteriorly. Occiput dull black. Antenna brown; basoflagellomere semicircular, paler baso-ventrally; arista pilose. Thorax. Colour black, postpronotum brownish, all densely pale pollinose; scutum with short, adpressed reddish pile; scutellum semi-circular, ratio of length:width 1:2.3; the pile similar to posterior part of scutum, with a pair of long, thin, pale convergent setae at apical margin; the pile on pleura rare, adpressed and pale. Wing. Hyaline, stigma yellow. Legs. Pro- and mesoleg entirely yellow. Metaleg: coxa brownish; trochanter simple, yellow; femur dark brown, the basal 1/4 yellow; tibia without apico-ventral tooth, yellow, the apical 1/4 brown, with track of subbasal brownish annulus; tarsus brown. Abdomen. Length ratio of tergites I, II, III and IV 1:4.0:3.0:2.0. Tergites shiny black, the anterior 1/2 of tergite III yellow; the pile of tergites pale, dense, adpressed, short, longer on tergite IV, and becoming longer towards the lateral margin; tergite I with a subvertical row of long, thin, pale setae laterally; sternite IV ( Fig. 38 D) brown, the posterior lobe yellow, the pile pale; sternites VI–VIII simple, black, the pile pale. Genitalia, Figs 38 A–D. Note the symmetrical surstyli and superior lobe and the unusual lobes on the superior lobe. FEMALE. Unknown.

Type material. HOLOTYPE. ♂, N.E. Burma, Kambaiti, 7000 ft, 14.v.1934, R. Malaise ( SMNH). PARATYPE. 1♂ with same data as holotype except 12.v. ( NBC).

Etymology. The name is Latin, pollinosa , dusty or pollinose, referring to the general rather heavy pollinosity of the fly.

Discussion. Sphegina pollinosa is similar to S. pollex and S. culex . Male abdominal sternite IV is rather similar to that of S. culex in ventral view and differs from that of S. pollex by having the posterior membranous incision large. Except for the characters mentioned in the key the three species are distinguished by the following characters in the male genitalia ( Figs 38 , 39 , 40 ): in S. pollinosa the dorsal lobe of surstylus is much broader than in the two others, and like S. culex lacks a subbasal medio-dorsal thumb-like sublobe (present in S. pollex ) and the superior lobe is unusual, composed of several sclerites (usual and simple in the two others).

Figures

FIGURE 38. Sphegina (Asiosphegina) pollinosa sp. n. (holotype). A. Genitalia, lateral view. B. Left surstylus, lateral view. C. Left superior lobe, lateral view. D. Tergites III and IV and sternite IV, lateral view. Scale 0.5 mm.

FIGURE 39. Sphegina (Asiosphegina) culex sp. n. (holotype). A. Sternite IV, ventral view. B. Left surstylus, lateral view. C. Left superior lobe, lateral view. D. Genitalia, lateral view. Scale 0.5 mm.

FIGURE 40. Sphegina (Asiosphegina) pollex sp. n. (holotype). A. Posterior part of sternite IV, ventral view. B. Left surstylus, lateral view. C. Left superior lobe, lateral view. D. Genitalia, lateral view. Scale 0.5 mm.