Megaselia labellifera Borgmeier 1969

Megaselia (Megaselia) labellifera

MALE.—Length 1.40 mm. Head width 0.46 mm. Frons black, slightly broader than long laterally (6:5), width 0.23 mm, pubescent, with a distinct median line. Su unequal, the lower thin and about one-half of the upper, the upper nearly one-fourth of frontal width apart, the lower one-ninth. Antials in line with upper su, farther from them than from anterolaterals which are a little higher near eye-margin. One upper and one lower postocular bristle. Cheeks with 2 or 3 setulae. Third antennal joint black, of normal size, globose; arista 0.39 mm, finely pubescent. Palpi brown, of normal shape, with bristles of moderate length. Proboscis short, dark brown; labellae large, shield-shaped, each labella excavated ventrally.

Thorax black-brown. Pubescence short, longer behind. Mesopleura bare. Scutellum with 2 bristles and 2 minute hairs.

Abdomen black-brown, venter dark. Tergites sub-equal in length, with scarce short pubescence, hairs on hind margin of 6th tergite bristle-like. Venter sparsely hairy. Hypopygium (Figure 59) small, dark brown, with some fine bristly hairs; ventral plate large, hairy. Anal segment short, yellowish brown, end-hairs hardly longer than the other hairs. Legs castaneous. Foretibia 0.28 mm; fore tarsus slender; metatarsus as long as 2 + 3. Midtibia 0.33 mm. Hind femur (Figure 60) nearly 3 times as long as broad, on basal half of ventral edge with about 7 longish curved hairs. Hind tibia 0.46 mm, with 10 short posterodorsal setulae.

Wing (Figure 58) distinctly yellowish brown, veins brown. Length 1.17 mm, width 0.52 mm. Costa 0.48 of wing length, ratio of segments 18:14:7. Cilia short (0.078 mm), there are 6 pairs between tip of 1st vein and apex of costa. Mediastinalis distinct. Fork acute. Third vein without a bristle at base; 4th vein curved near base, remainder nearly straight; 5th and 6th slightly sinuous; 7th weak. Axillary margin with 2 hairs. Halteres black.

Holotype, on slide (USNM 70254), Dominica, S. Chiltern Est. 20 Feb. 1965 (Wirth).