About Pachypsylla celtidisvesicula Riley, 1890
Pachypsylla celtidisvesicula, commonly known as the hackberry blistergall psyllid, is a species of aphalarid psyllid native to North America. Nymphs of this species induce the formation of blister-like galls on the leaves of various hackberry species (Celtis spp.) across the entire area where the psyllid occurs. This species is closely related to the more widespread hackberry nipplegall psyllid (Pachypsylla celtidismamma), and adult individuals of the two species strongly resemble one another.
