Pachybrachis spumarius Species-Group

Barney, Robert J., 2017, Definition and Revision of the Spumarius Species-Group of North American Pachybrachis Chevrolat (Coleoptera: Chrysomelidae: Cryptocephalinae), The Coleopterists Bulletin 71 (3), pp. 449-460 : 451

Pachybrachis spumarius Species-Group

Group Diagnosis. Small beetles, measuring 1.75–2.63 mm in length. Dorsum yellow, glabrous, with brown, reddish brown, or rust-colored punctures; standard maculae diffuse, often dark brown or fuscous. Eyes of male moderately separated (IOD = 0.17–0.30 mm); front without ocular lines. Protarsal claws of males not or slightly enlarged. Median lobe in en-face view widest at base, narrowing to a gently rounded ALM with a prominent nodule, varying to a circular orificial space formed by a midpoint constriction; lateral basal plates moderately sclerotized; in lateral view, ventral surface well-inflated at base, forming tube-like median lobe that narrows sharply to terminus; ventral keel absent; setal beard short and fine at apicolateral angle; pencilli absent.

Biology. Almost nothing is known of the biology of the members of the spumarius species-group . Series of P. spumarius have been repeatedly collected on Rhus spp. (Anacardiaceae) . Larvae and larval habitats are unknown.