Length: 9-14 mm
Arthromacra aenea is metallic green to coppery, with pale antennae. The overall shape is slender and elongate. Look too for dark legs with pale tarsi.
The Long-Jointed Beetles once made up their own family, Lagriidae, but taxonomists now consider them to be a subfamily within the Darkling Beetles. The common name "Long-Jointed" refers to the apical antennal segment, which is much longer than the other segments, especially in males.
Adults may be found on foliage, and are attracted to lights.
Insects of West Virginia