Insect of the Week (July 16, 2018) - The new canola flower midge (Contarinia sp., Diptera: Cecidomyiidae)

This week’s Insect of the week is a new find on the prairies, tentatively called the canola flower midge, Contarinia sp. (Diptera: Cecidomyiidae). The canola flower midge has been found throughout central Alberta, Saskatchewan, and the Swan River Valley in Manitoba. The female lays eggs on developing canola flower buds. Upon hatching, the larvae feed within the developing flower and cause the formation of a “pop-bottle”-shaped gall. To date, this is the only damage associated with the midge, and it has been minimal across the prairies.

Adult canola flower midges appear similar to swede midge (Contarinia nasturtii). They are tiny, delicate flies, 2-5 mm in size. They can be differentiated from swede midge based on the appearance of the female antennae, the damage symptoms they produce and genetically.

Many thanks to Scott Meers and Shelley Barkley (Alberta Agriculture and Forestry) for organizing the Alberta surveys for the canola flower midge.  

Submitted by Dr. Boyd Mori and Dr. Meghan Vankosky

Find out more about the insect pests that plague your crops and the natural enemies that keep them in check at the Insect of the Week page!

“Pop-bottle”-shaped galls created by the canola flower midge.
(c) 2016 Boyd Mori, AAFC