Hypselosyrphus vexillipennis, Reemer, Menno, 2013

Reemer, Menno, 2013, Taxonomic exploration of Neotropical Microdontinae (Diptera: Syrphidae) mimicking stingless bees, Zootaxa 3697 (1), pp. 1-88 : 38-40

Hypselosyrphus vexillipennis spec. nov.

Figs 105–107.

Studied type specimens. HOLOTYPE. BRAZIL. Female. Label 1: " 1.I.1955 / Barueri / S. Paulo / 3409"; label 2: "K. Lenko leg.". Coll. USNM.

PARATYPES. BRAZIL. Female. Label 1: " BRASIL Rio de Janeiro / D.F. Corcovado / XI.1957 / Seabra e Alvarenga”. Coll. MZUSP.

Female. Label 1: "Barueri, / São Paulo, Brasil / 15.I.1966 / K. Lenke col.". Coll. MZUSP.

Redescription (based on holotype)

Adult female Body size: 10 mm.

Head. Face occupying 1/5 of head width in frontal view; black; entirely white pilose. Gena hardly developed. Oral cavity directly bordering eye margins; with lateral margins not produced. Frons black; sparsely black pilose medially, white pilose along lateral margins. Vertex convexly produced, shining black; black pilose; ocellar triangle not elevated compared to rest of vertex. Occiput black; very narrow, barely visible in lateral view; dorsally black pilose; ventrally white pilose. Eye entirely with short, pale pile, a little longer than ommati diameter. Antennal fossa a little higher than wide. Antenna black, except basoflagellomere blackish brown; antennal ratio approximately as 5:1:2.5.

Thorax. Scutum, postpronotum and postalar callus dark brown; densely black pilose. Scutellum trapezoid, with posterior margin apicomedially slightly sulcate; dark brown; black pilose. Anepisternum convex, without sulcus; dark brown; anterior part and posterior margin black pilose. Anepimeron entirely black pilose. Katepisternum dark brown; black pilose dorsally; bare ventrally. Katatergum long black microtrichose. Anatergum short microtrichose. Other pleurae bare. Calypter brown, halter yellowish white.

Wing: dark brown on basal 3/5 and apical 1/5, with yellow fascia of 1/5 of wing lentgh in between, somewhat infuscated around vein DM-Cu; colours most clear on anterior half, fading posteriorly. Microtrichose, except bare on 1st costal cell, basal 1/6 of cell br, basal 1/10 of cell bm.

Legs: Brown; black pilose, except yellow pilose on apical four tarsomeres of front and mid tarsus.

Abdomen. More or less oval, but apical segments narrower than basal ones; a little wider than thorax, widest at posterior 1/4 of tergite 2. Tergites dark brown; black pilose, except tergites 1, 5 and posterolateral corners of tergite 4 yellow pilose. Basal sternites pale brown, apical sternites darker; yellow pilose.

Male. Unknown.

Etymolgy. The name vexillipennis (flag-winged) refers to te painted wings of this species.

Diagnosis. The wing marks and the unwidened hind-tibiae of this species immediately distinguish it from other known Hypselosyrphus -species, except H. pingo . From that species it differs by the completely black scutum and scutellum (yellowish brown pilose in H. vexillipennis ).

Notes. Compared with the holotype, the paratype is darker, almost black, in overall colouration. In this species the hind tibiae are not widened or corbiculate, unlike in other species of Hypselosyrphus (except H. pingo ) and Stipomorpha. It is a matter of taste whether this species should be considered as a mimic of stingless bees or not. Nevertheless, it posesses all characters described as diagnostic for Hypselosyrphus .

Distribution. Only known from Brazil (São Paulo & Rio de Janeiro).