Microdon (Myiacerapis), Hull

Reemer, Menno & Stahls, Gunilla, 2013, Generic revision and species classification of the Microdontinae (Diptera, Syrphidae), ZooKeys 288, pp. 1-213 : 45-46

Subgenus Myiacerapis Hull Figs 215-220

Myiacerapis Hull, 1949: 309. Type species: Microdon villosus Bezzi, 1915: 135, by original designation.

Description.

Body length: 12 mm. Broadly built flies with bee-like pilosity and long antennae. Head wider than thorax. Face convex; wider than an eye. Lateral oral mar gins not produced. Vertex flat. Occiput ventrally narrow, dorsally widened. Eye bare or very short and sparsely pilose. Eye margins in male hardly converging at level of frons, with mutual distance about 5 times as large as width of antennal fossa. Antennal fossa about as wide as high. Antenna longer than distance between antennal fossa and anterior oral margin; basoflagellomere longer than scape; bare. Postpronotum pilose. Scutellum semicircular; without calcars. Anepisternum weakly sulcate; pilose anteriorly and posteriorly, widely bare in between. Anepimeron entirely pilose. Katepimeron convex; with wrinkled texture; bare. Wing: vein R4+5 with posterior appendix; vein M1 slightly recurrent, but more or less perpendicular to vein R4+5; postero-apical corner of cell r4+5 rounded, without appendix; crossvein r-m located around basal 1/4 of cell dm. Abdomen oval, about 1.5 times as long as wide. Tergites 3 and 4 fused. Sternite 1 pilose. Male genitalia: phallus furcate, with furcation point near base; epandrium with ventrolateral ridge; surstylus unfurcate.

Diagnosis.

Abdomen oval, about 1.5 times as long as wide. Vein R4+5 with posterior appendix. Postpronotum pilose. Proepimeron bare. Antenna longer than distance between antennal fossa and anterior oral margin. Basoflagellomere longer than scape. Anepisternum with bare ventromedian part extending to dorsal half. Sternite 1 pilose. Scutellum without calcars.

Discussion.

Myiacerapis was described as a subgenus of Microdon . In morphology it is quite similar to Microdon s.s. as defined in the present paper, also in the male genitalia (deeply furcate phallus with equally long processes, epandrium with ventrolateral ridge). However, unlike Microdon s.s. it has a bare proepimeron (pilose in Microdon s.s.) and a wrinkled texture of the katepimeron. Therefore, it is not placed in Microdon s.s. here, but in Microdon s.l, in awaitance of better understanding of its phylogenetic affinities.

Diversity and distribution.

Described species: 1. Africa (Uganda). An undescribed species is known from South Africa (coll. BMNH).