There are approximately 16 genera and 455 species of soldier beetles in North America. Most adults eat nectar and pollen, although a few are reported to eat other insects like aphids. Larval soldier beetles are generally carnivorous and feed on small soft-bodied insects.
Two of the more common soldier beetles are:
Margined Leatherwing
(Chauliognathus marginatus)
The identifying characteristic of the Margined Leatherwing Beetle is the wide black line running from front to rear down the middle of its pronotum (the short body segment between head and abdomen. The Margined Leatherwing is also most likely to be seen in the spring and early summer. (Photo from 5/17/06)
Goldenrod Soldier Beetle
(Chauliognathus pensylvanicus)
The Goldenrod Soldier Beetle has an irregularly shaped dot in the middle of its pronotum. The dot does not run all the way to the front or rear. This beetle is also most likely to be seen in the late summer and fall. (Photo from 9/6/08)
(The amount of black on the elytra of both species varies among individuals and is not significant for making an ID.)
Sources and additional information:
BugGuide: Goldenrod Soldier Beetle
BugGuide: Margined Leatherwing Beetle
University of Kentucky: Soldier Beetles
Chicago Wilderness Magazine: Margined Soldier Beetle
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