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Genus Alydus

Alydus eurinus Alydus pilosulus ? - Alydus pilosulus Broad-headed Bug - Alydus pilosulus Stairs bug - Alydus Alydus pilosulus Herrich-Schäffer - Alydus pilosulus Ant, sawfly, something else? - Alydus eurinus Alydid - Alydus eurinus Bug ~11mm - Alydus
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 Coreoidea (Leatherbugs)
Family Alydidae (Broad-headed Bugs)
Subfamily Alydinae
Genus Alydus
Other Common Names
Ant Bugs
Explanation of Names
Alydus Fabricius 1803
6 spp. in our area, 9 total(1)
11-15 mm
Elongate, dark bugs with very broad heads. Some species have red mark on abdomen, possible mimicry of wasps. Nymphs resemble ants.
Key to eastern species [adapted from(2)]:
-Pronotum with humeral angles acute, the side margins calloused and pale-->pilosulus
-Pronotum with humeral angles obtusely rounded, the side margins not distinctly paler than the disk
Head and pronotum with numerous erect hairs; pronotum usually blackish-bronzed, rather coarsely and densely punctate; membrane dark without fuscous spots; claspers of male twisted, not curved; lateral plates of female genitalia acute at apex-->eurinus
Head and pronotum with few if any erect hairs; basal half of pronotum brown, very finely and sparsely punctate; membrane pale with vague fuscous spots; claspers of male curved, divaricate at base, convergent at tip; lateral plates of female genitalia broadly rounded at apex-->conspersus
images of several spp., incl. those not yet in the guide, here(3)
Holarctic and Oriental(1)
Varied: fields, forest edges, usually found on herbaceous plants
May-frost in NC(4); Jun-Oct in MN (adults typically late summer)
Suck plant juices, but sometimes found on carrion. A. eurinus and A. conspersus often found on bush-clover, Lespedeza.