Goldenrod Soldier Beetle

Description:

Bright yellow insect, with hard outer wings covering lacy black wings. The outer wings are seen here as yellow with a large black oval on each wing. The body of the insect was rectangular (much like a lightning bug), and was yellow with black stripes. The insect itself wasn't very large (about 3/4 cm long), but it had extremely long antennae (over 1 cm), as you might be able to see from the picture.

Habitat:

Found in HUGE quantities (hundreds in just a small area) on a wild flower prairie at Beaver Creek State Park in SD.

Notes:

We thought this was a type of lightning bug, as it's shape and size are identical to that, but could not find a similar pic anywhere. We would appreciate any thoughts on the species!