Bark-feeder
Guides
Longistigma
giant bark aphid
Longistigma is a genus of giant aphids in the family Aphididae, containing at least three described species. These are the largest aphids in North America, with Longistigma caryae (giant bark aphid) being particularly notable for its size. The genus was established by Wilson in 1909 based on the extremely long, slender stigma that extends around the end of the wing. Members of this genus feed on bark and are associated with trees including oak, hickory, walnut, and beech.
Pterocomma salicis
Black willow bark aphid
A bark-feeding aphid specialized on willow trees, commonly known as the black willow bark aphid. Forms mutualistic relationships with ants, particularly Lasius niger, which actively transport and tend colonies. The species has been documented in ant-mediated dispersal studies, suggesting ants may evaluate host quality when relocating aphid colonies.