Spurge hawkmoth - Hyles euphorbiae
The Spurge hawkmoth, Hyles euphorbiae (Sphingidae), was the first classical biological agent released against leafy spurge in the United States, with approval for introduction granted in 1965. The moth was also introduced from Europe into Ontario, Canada, to help control various weed spurges, and then into Alberta where specimens are occasionally still taken.
Originally the Spurge hawkmoth occurs from south and central Europe to central Asia.
Caterpillars may approach 10 cm in length, and are variously patterned with green, yellow, and black (young); or red, black, yellow, and white (older). They are distinctive by having the so-called “ring-spots” (spots that lack a nucleus), which is thought to have an aposematic function, being used as signals of distastefulness.
The body of the adult moths is light brown with various white and dark brown markings, while the wings have a conspicuous tan, brown, and pink or red color pattern. The upperside of the hindwing is a rosy-pink, but there is a great deal of variation among the adults.
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Photo credit: [Top: ©Adam Gor | Locality: Nagykovácsi, Pest, Hungary, 2013] - [Bottom: ©Tony Morris | St. Margaret’s at Cliffe, England, 2007]