External images
For terms see Morphology of Diptera
The wing length is 6·5-7·25 mm.
Apical antennomere small and without a sensory pit. Arista almost bare. Face less produced than in Brachyopa bicolor.[6] Scutellum with microtrichia only on anterior margin. The larva is illustrated by Rotheray (1993).[7]
Distribution
Brachyopa insensilis is a Palearctic species with a wide distribution in Europe[8] and east to Tajikistan, Siberia, Russian Far East and Kamchatka.[9]
The habitat is Abies, Quercus and Fagus forest with senile trees, but also occurs on old trees in suburban parks.[10]
Behaviour
Brachyopa insensilis is arboreal descending to visit sap runs and flowers (white umbellifers, Photinia, Prunus padus, Sorbus aria.[11] The flight period is from the beginning of May to the end of June. Brachyopa insensilis has a characteristic, rapid, zigzag flight and rarely descends lower than 3 metres from the ground. It may occur in small swarms around sap runs. Larvae feed in sap runs and rot holes.
^Stubbs, Alan E. & Falk, Steven J. (1983). British Hoverflies: An Illustrated Identification Guide (2nd (revised) ed.). British Entomological & Natural History Society. p. 271, xvpp. ISBN0-9502891-3-2.
^Van Veen, M. (2004) Hoverflies of Northwest Europe: identification keys to the Syrphidae. 256pp. KNNV Publishing, Utrecht.
^Van der Goot,V.S. (1981) De zweefvliegen van Noordwest - Europa en Europees Rusland, in het bijzonder van de Benelux. KNNV, Uitgave no.32: 275pp. Amsterdam.
^Bei-Bienko, G.Y. & Steyskal, G.C. (1988) Keys to the Insects of the European Part of the USSR, Volume V: Diptera and Siphonaptera, Part I. Amerind Publishing Co., New Delhi. ISBN81-205-0080-6.
^Rotheray G., 1993 Colour Guide to Hoverfly Larvae Diptera, Syrphidae in Britain and Europe Dipterists Forum pdfArchived 2019-04-03 at the Wayback Machine
^de Buck, N. (1990) Bloembezoek en bestuivingsecologie van Zweefvliegen (Diptera, Syrphidae) in het bijzonder voor België. Doc. Trav. IRSNB, no. 60, p. 1-167.