Bullington, S.W., & Kosztarab, M.P. 1977 Morphology and taxonomy of gall-like insects Kermes spp. (Homoptera: Kermesidae) in Eastern North America.. Journal of the New York Entomological Society 85: 168-169.

Notes: Abstract only; separation of species recommended by examination of flaps or "pseudoventer", which project from highly vaulted venters attached to the substrate on postreproductive females; these flaps appear to differ in number, shape, or location depending on species.