|Delia floralis |
It occurs mainly in agriculture land infesting Cruciferae crops. The main cultivated hosts in the Canadian Prairie Provinces are turnip, rutabaga, cauliflower, cabbage and rapeseed canola varieties. Strickland (1938) reported that in 1929 this species destroyed a large areas of stinkweed (Thlaspi arvense L.) in the Peace River Region of northern Alberta.
Adults are found during early-to late June in the northern Alberta.
Delia floralis may be distinguished from other Delia species occurring in the field by the following combinations of characters: In males, in the hind femur, the long setae (anteroventral setae) commences close to the base and there are no posteroventral setae except at the base and the tip. The 5th sternite processes have 3-4 outstandingly long pairs of outer lateral setae. In females, the hind femora have an uninterrupted row of anteroventral setae but lack posteroventral setae on basal half.
Appears to be one generation a year in the Prairie provinces of Canada. Females lay their eggs close to the host plants normally in large batches. Hatching takes 1-3 weeks, and larvae feed on roots. After five to six weeks the larvae are fully developed and pupariate in the soil, where they overwinter.
Not of concern.
Larvae of Delia floralis feed on roots of host plants.
This species is native to Western North America. The known range extends from subarctic localities ( Firth river, Yukon Territory; Reindeer Depot, North western Territories) to Colorado and California (Huckett 1965).
As cited by Griffiths(1991) Delia planipalpis (Stein) is included under Delia radicum subsection along side with Delia radicum ( Linnaeus) and Delia floralis (Fallen). Hylemyia planipalpis (Stein) is one of the synonyms used for this species in the past. There are a wide range of natural enemies from families Carabidae and Staphalinidae of order Coleoptera and Family Cynipidae of order Hymenoptera are associating with Delia planipalpis as in the case of Delia radicum.
|species page author||Subramaniam, R.||2007 |