Metadon achterbergi Reemer

Reemer, Menno & Stahls, Gunilla, 2013, Generic revision and species classification of the Microdontinae (Diptera, Syrphidae), ZooKeys 288, pp. 1-213 : 104-105

Metadon achterbergi Reemer sp. n. Figs 163-166

Type specimens.

HOLOTYPE. Adult female. VIETNAM. Label 1: "C. VIETNAM: Ha Tinh / Vu Quang N.P., 53 m, N 18° / 20'50" E105°26'37.8", 22.ix.- / 6.x.2009, Mal. trap 1, RMNH-09 / C. v. Achterberg & R. de Vries". Coll. RMNH. Voucher code M. Reemer: 284. DNA voucher labcode MZH:Y1086.

Diagnosis.

Within Metadon , five other described Oriental species have a dark (sub)apical wingspot. These species are listed here (in parentheses a character is given that distinguishes them from Metadon achterbergi sp. n.): Microdon auricinctus Brunetti, 1908 (tergite 4 red); Metadon bicoloratus Hull, 1944 (thorax and abdomen without fasciae of golden pile); Metadon fuscicornis Sasakawa, 1960 (wing infuscated at entire apical half); Metadon pendleburyi Curran, 1931 (thorax and abdomen without fasciae of golden pile); Metadon wulpii Mik, 1899 (mesoscutum without fascia of golden pile along transverse suture, scutellum reddish brown).

Description (based on holotype).

Adult female. Body size: 13 mm.

Head. Face occupying about 1/3 of head width in frontal view; dark brown; golden pilose, very narrowly bare medially on ventral half. Gena brown, golden pilose. Lateral oral margin produced. Frons, vertex and occiput brown; golden pilose, except occiput ventrally white pilose. Eye bare. Antennal fossa about as high as wide. Antenna black; antennal ratio approximately as 4:1:3.

Thorax. Mesoscutum blackish brown; golden pilose, with transverse fasciae of thicker golden pile along anterior margin, transverse suture (fascia medially interrupted) and posterior margin. Postpronotum and postalar callus yellow; golden pilose. Scutellum semicircular; blackish brown; golden pilose. Anepisternum with deep sulcus; yellowish brown; entirely golden pilose. Anepimeron yellowish brown; entirely pilose. Katepisternum blackish brown; golden pilose dorsally, very sparsely pilose ventrally. Other pleurites yellowish brown. Katatergum long microtrichose, anatergum short microtrichose. Calypter and halter yellowish.

Wing: Yellow on basal 2/3, blackish on apical 1/3, with colouration in posterior half less conspicuous. Microtrichose, except bare on cell bc, narrowly along vein Rs in cell r1, basal 3/4 of cell br, basomedian 3/4 of cell bm, anterobasal 1/4 of cell cup, and basomedian 9/10 of alula.

Legs: Yellow; yellow pilose. Front coxa yellow, mid and hind coxae blackish brown; yellowish pilose. Trochanters blackish brown; yellowish pilose.

Abdomen. Tergites black. Tergites 1 and 2 golden pilose. Tergite 3 golden pilose anterolaterally; black pilose otherwise. Tergite 4 with fascia of golden pile along anterior margin, laterally widening and expanding along lateral margin, and with pair of sublateral oblong maculae of golden pile, black pilose in between. Tergite 5 golden pilose anterolaterally, black pilose otherwise. Sternites blackish brown; pale pilose, except sternite 5 mostly black pilose.

Male. Unknown.

Etymology.

This species is named after its collector, Dr. C. van Achterberg, in acknowledgment of the many ways in which he has been helpful to the senior author during his PhD work. The epithet is a noun in the genitive case.