|scientific name Euxoa divergens |
common name Divergent Dart
Open areas, including dry open woodlands.
In Alberta adults have been collected mid-June to mid-August, with the main flight in late June.
A medium-sized (3.1-3.5 cm wingspan) dark brown moth. The forewings are dark brown or dark grey-brown with a black basal dash and a contrasting pale cubital vein. Most likely to be mistaken for specimens of E. ridingsiana or some forms of E. tessellata. Divergens lacks the pale streak distal to the claviform spot and the streaking in the subterminal area found in ridingsiana. Males can also be distinguished by the long saccular extensions (longer than the harpes in divergens, half as long as the harpes in ridingsisana). Females of the two species can be separated by the absence in divergens of the sclerotized flanges on the ovipositor lobes found in ridingsiana. Males of divergens can be separated from those of tessellata by the absence of the yellow scale tufts at the forewing base found in tessellata, as well as by the more cylindrical saccular extensions and the less apically expanded cucullus in divergens. The ovipositor lobes of divergens are rounded and covered in fine setae; those of tessellata are truncate and covered in short, conical setae.
Specimens of divergens can be quite variable in both ground color (almost black to light grey-brown) and extent of white scaling along the cubital veins (well-marked to reduced to a few light scales). Divergens belongs in the subgenus Longivesica, characterized by the extremely long vesica in males and the appendix bursa being longer than the corpus bursa in females. Lafontaine (1987) provides keys to the subgenera and species and illustrates adults and the genitalia of both sexes.
Divergens is single brooded, and the adults are nocturnal and come to lights and bait. The immature stages are known only from laboratory-reared material. It is one of the earliest species of Euxoa on the wing in Alberta.
A common widespread species; no concerns.
No data; like most members of the genus, probably a general feeder on low plants.
Newfoundland to Alaska, south to New York and Michigan in the east, and in the mountains of the west south to New Mexico, Arizona and California. Present throughout much of Alberta, from the Milk River north to Zama, but apparently largely replaced by E. sinelinea in the northeastern part of the province.
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