Homaemus aeneifrons – Bronze-Headed Shield Bug

Early Sunday morning I saw a group of bronze-headed shield bugs (Homaemus aeneifrons) sunning themselves on the seed heads of Canadian hawkweed (Hieracium umbellatum). The previous night had been very cool with temperatures dipping to 40 degrees F and this cluster of seed heads facing due east into the sun was a perfect place to warm up. In all, there were six bugs catching the early morning sun.

Homaemus aeneifron is widespread in North America occurring as far south as Kansas and Arizona and as far west as Alaska, British Columbia, and California. It is frequently found in moist meadows and weedy areas. Some reports state that it feeds on grasses and sedges (Carex) and rushes (Juncus) but one has it feeding on Monarda fistulosa (wild bergamot) and Oenothera biennis (evening primrose). These on hawkweed did not appear to be feeding. Beyond catching some rays it was hard to say why they were all there.

CLASSIFICATION
Kingdom: Animalia (Animals)
Phylum: Arthropoda (Arthropods)
Subphylum: Hexapoda (Hexapods)
Class: Insecta (Insects)
Order: Hemiptera (True Bugs, Cicadas, Hoppers, Aphids and Allies)
Suborder: Heteroptera (True Bugs)
Infraorder: Pentatomomorpha
Superfamily: Pentatomoidea
Family: Scutelleridae (Shield-backed Bugs)
Subfamily: Pachycorinae
Genus: Homaemus
Species: aeneifrons (Homaemus aeneifrons)

SOURCES

Bug Guide

Williams, Andrew H. 2004. “Feeding Records of True Bugs (Hemiptera: Heteroptera) From Wisconsin,” The Great Lakes Entomologist, vol 37 (1)

Thomas, Donald B.; Werner, Floyd G. 1981. Grass Feeding Insects of the Western Ranges: An Annotated Checklist. Technical Bulletin (University of Arizona, Agricultural Experiment Station) No. 243