Doros aequalis Loew
Synonym:
Syrphus vittatifrons Harris, 1835: 598 (nomen nudum; a Say manuscript names it according to Johnson 1925).
Synonym:
Syrphus vittatifrons Harris, 1835: 598 (nomen nudum; a Say manuscript names it according to Johnson 1925).
Species elongate, robust, wasp-like, with wing darkened anteriorly; with abdomen parallel-sided, margianted at least on terga 4th and 5th and with narrow yellow maculae or fasciae on terga. Only Nearctic species of the genus Doros, with abdomen less petiolate than Palaeractic species.
D. aequalis has katepisternum with dorsal yellow macula, and the abdomen strongly convex in cross section.
New description:
MALE.
Head: Face with facial tubercle, yellow dorsally and medially, brown ventrad to mouth tip, black pilose; gena brown, yellowish pilose; lunule dark brown; frontal triangle yellow, black pilose; vertical triangle black, black pilose; holoptic, eye bare; antenna dark brown,black pilose; occiput black, silver pollinose, withish-yellow pilose except black pilose on dorsal 1/4.
Thorax: scutum black with 2 dorsomedial grey pollinose vittae and two small yellow maculae on posterior margin close to scutellum, yellow and black pilose; postpronotum bare, yellow; notopleuron and supra-alar area mostly yellow, black lateral half, yellow pilose except black pilose on black area; postalar callus black; scutellum yellowish, black pilose with few yellow pili on anterior margin. Pleuron mostly black, except proepimeron with small yellow macula, and katepisternum with dorsal yellow macula; anterior anepisternum bare; metasternum bare; calypter yellow, fringe with yellow pile; plumula brown; halter brownish yellow; spiracular fringes yellow. Wing: Wing membrane yellowish, almost hyaline, dark yellow to brown on anterior margin (costal cells, stigma and area around furcation of RS; entirely microtrichose. Alula broad, microtrichose. Legs entirely brown except apical extreme of femora and basal half of tibiae yellow.
Abdomen: Almost parallel-sided, strongly convex in cross section, 4th and 5th terga vaguely margined. Dorsum mainly black, black pilose dorsally and laterally except 1st tergum yellow pilose laterally; 2nd tergum yellow pilose laterally on anterobasal 2/3 and dorsally on yellow maculae, and 3rd tergum yellow pilose laterally on basal 1/4; 1st tergum black; 2nd tergum black with 2 mesolateral oblique yellow maculae; 3rd and 4th terga black with a narrow, about 1/3–2/5 of tergum length, yellow fascia on anterior 1/3 of the tergum, medially divided; 4th tergum with narrow yellow fascia on posterior margin; 5th tergum black with medial triangular yellow macula on posterior margin; sterna black with yellow fascia on anterior and posterior margins, mostly yellow pilose.
Species strongly resembling wasps of genus Ancistrocerus Wesmael (Eumenidae) (Vockeroth 1992).
Body length: 11.5-15.5 mm.
From Wisconsin to Quebec, south to North Carolina.
Doros aequalis Loew, 1863.
Loew, H. (1863) Diptera Americae septentrionalis indigena. Centuria quarta. Berliner entomologische reitschrift 7, 275-326.