Microdon irwini Reemer sp. n.

(Figs 26–31)

Diagnosis. One of the two known Madagascan Microdon species with bronze coloured abdomen. Distinguishable from M. tsara by its largely black tibiae and entirely microtrichose alula.

Type material. HOLOTYPE. Adult male. MADAGASCAR. Label 1: " MADAGASCAR: Fianarantsoa / Prov., Parc National Ranomafana, /radio tower at forest edge, elev. / 1127 m., 12-25.vii.2005, ex: malaise / trap, 21°15.05'S 47°24.43'E, coll: / M. Irwin & R. Harin'Hala, MG-09B-119". Coll. CAS. PARATYPES. One male of same locality as holotype, but date 26.ii-5.iii.2005 (coll. RMNH). One female of Madagascar, Fianarantsoa Prov., Belle Vue, 1.2 km S of Ranomafana National Park entrance, Malaise in rainforest, 28.i- 4.ii. 2002, 1095 m., 21°15.99'S 47°25.21'E, leg. R. Harin'Hala & M.E. Irwin (coll. CAS).

Description of male holotype. Body size: 7 mm. Head. Face and gena black with strong bronze sheen; golden yellow pilose. Oral margin not produced. Frons blackish brown; black pilose anteriorly, golden yellow pilose posteriorly. Vertex bronze black; golden yellow pilose. Occiput bronze black; golden yellow pilose, thin white pollinose. Eye bare. Antennal fossa about as wide as high. Antenna with scape and pedicel brown, basoflagellomere black. Arista brown, about 4/5 of length of basoflagellomere. Thorax. Mesoscutum, postpronotum and postalar callus bronze black; long erect golden yellow pilose. Scutellum trapezoid, almost triangular; bronze black; golden yellow pilose; with pair of apical calcars approximately as long as half the length of the scutellum, with mutual distance about 1/4 of width of scutellum at base. Pleuron black. Propleuron bare. Anepisternum with slight sulcus separating anterior from posterior part; golden yellow pilose anteriorly and posterodorsally, with widely bare part in between. Anepimeron entirely golden yellow pilose. Katepisternum white pilose dorsally, bare ventrally. Katepimeron without pile, shining. Katatergum and anatergum long and short microtrichose, respectively. Calypter yellow, halter white. Wing. A little greyish antero-apically. Microtrichose, except bare on cell bc, basal 1/6 of c, basal 1/5 of r1, basal 3/4 of br, basal 4/5 of bm, and anterobasal 1/6 of cell cup. Legs. Femora blackish brown, somewhat paler posteriorly; black pilose, except white pilose posterobasally. Tibiae blackish brown, except yellow at apical 1/4 to 1/3; black pilose. Tarsi yellow; mixed yellow and black pilose. Coxae and trochanters blackish; white pilose, except fore coxa apically golden yellow pilose. Abdomen. Tergite 1 black; white pilose. Tergite 2 bronze black, except duller black anteromedially; golden yellow pilose. Tergite 3 bronze black, except duller black on anterior 1/3; golden yellow pilose. Tergite 4 bronze shining, black ground colour hardly visible, with ground colour posteriorly yellow; golden yellow pilose. Pregenital segments yellow; yellow pilose dorsally, black pilose ventrally. Sternites blackish brown. Sternite 1 bare. Sternite 2 yellow pilose. Sternites 3 and 4 mixed black and yellow pilose. Male genitalia as in Fig. 29.

Female. Body size: 8 mm. As male, except for usual sexual dimorphism.

Etymology. This species is named after Mike E. Irwin, one of the collectors of the specimens on which this description is based.