Williams, D.J. 1987c Phenacoccus gossypii Townsend & Cockerell, P. madeirensis Green and some related mealybug species (Hemiptera: Pseudococcidae).. Bulletin of Entomological Research 77: 335-356.

Notes: Identity of P. gossypii is established as a local species in Mexico and southern US; has been mistaken for P. gossypii; redescriptions and illustrations; P. harbisoni synonymized with P. madeirensis; P. baccharidis, new sp. described from Brazil; P. sphaeralceae, new sp. described from Arizona; P. hurdi redescribed; key to 15 related species in North and South America.