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Species Arocatus melanocephalus - Elm Seed Bug

Unknown species in Box Elder County Utah - Arocatus melanocephalus Arocatus 2 - Arocatus melanocephalus Arocatus 3 - Arocatus melanocephalus Elm Seed Bug - Arocatus melanocephalus little bug - Arocatus melanocephalus Heterogastridae? - Arocatus melanocephalus Lygaeidae - Arocatus melanocephalus Elm seed bug - Arocatus melanocephalus
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 Lygaeoidea
Family Lygaeidae (Seed Bugs)
Subfamily Lygaeinae
Genus Arocatus
Species melanocephalus (Elm Seed Bug)
Explanation of Names
Arocatus melanocephalus (Fabricius 1798)
5.5—7.5 mm
Native to, and widespread in S. & C. Europe, established and spreading in w. NA (BC-OR-ID-UT)(1)
Invades homes during summer, may stay through the winter
primarily elm seeds (Ulmus, Ulmaceae)(1)
Life Cycle
One generation per year; adults overwinter. Doesn't pose a threat to trees, but may show up indoors in huge numbers.
earliest record in our area: ID 2009(1)
Can emit unpleasant odor, especially when crushed
Internet References
First report in UT (Davis 2014)
Works Cited
1.First Canadian records for two invasive seed-feeding bugs, Arocatus melanocephalus (Fabricius, 1798) and Raglius alboacuminatus
Acheampong S., Strong W.B., Schwartz M.D., Higgins R.J., Thurston M.A., Walker E.J., Roberts J. 2016. J. Ent. Soc. B.C. 113: 74-78.