Didea alneti

Didea alneti is a Holarctic species of hoverfly.^[1][2][3]

Didea alneti
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Diptera
Family:	Syrphidae
Genus:	Didea
Species:	D. alneti
Binomial name
Didea alneti Fallén, 1817

Description

For terms see Morphology of Diptera

The wing length is 9 ·75-11·5 mm.

The face mostly yellow. Halteres with at least knob black or dark brown. Male vertex not long, less narrow than in Didea fasciata. Tergite 5 black, rarely with spots. Male tergite 4 with front edge of wedge-shaped bars clearly separated from the front margin of the tergite or just touching front of tergite on median line. ^{[4] [5][6]} The male genitalia and the larva are figured by Dusek and Laska (1967) .^[7]

Distribution

A Palearctic species with a wide distribution in Europe and East across Russia to the Pacific coast, Mongolia, Japan and Korea. ^[8][9] in North America from Alaska south to Colorado.^[10]

Biology

Habitat forest; conifer forest and taiga, Quercus woodland.^[11] Arboreal, descending to visit flowers of white umbellifers, yellow composites, Cirsium, Plantago, Potentilla, Rosa, Rubus idaeus, Salix, Sambucus ebulus, Valeriana officinalis, Viburnum opulus.^[12] The flight period is mid May to early September. The larva is arboreal and feeds on aphids associated with Larix, Prunus, Salix and Quercus.