Body oval; slightly rounded in lateral view; body color variable from light yellow to brown; legs red; covered by white, mealy wax; some specimens with medial wax crest; with faint submedial bare areas on abdomen of some specimens, these areas forming 1 pair of longitudinal lines on dorsum; ovisac absent; with 18 pairs of short lateral wax filaments, anterior pairs broken or very small, thim, posterior pairs broad, longest, about 1/8 or less of length of the body. Primarily occurring on subterranean parts of host, but occasionally on foliage. Surface of lateral filaments rough.
This species was intercepted 187 times at U. S. ports-of-entry between 1995 and 2012, with specimens originating from Austria, Azores, Bangladesh, Belgium, Canada, China, Colombia, Costa Rica, Dominican Republic, Ecuador, El Salvador, Guatemala, Guyana, Honduras, India, Indonesia, Israel, Italy, Jamaica, Japan, Kenya, Malaysia, Maldives, Mexico, Morocco, The Netherlands, Nigeria, Palestinian Territory, Peru, The Philippines, Puerto Rico, Singapore, Spain, South Africa, Syrian Arab Republic, Taiwan, Thailand, Vietnam and Zimbabwe. It is polyphagous; therefore, we have not recorded older quarantine records. ScaleNet lists the species from more than 30 families of host plants. It occurs in all zoogeographic regions but is most common in the new world. Several species of Phenacoccus other than P.defectus Ferris, P. franseriae Ferris, P. gossypii Townsend & Cockerell, P. hakeae Williams, P. helianthi (Cockerell), P. madeirensis Green, P. parvus Morrison, P. solani, P. solenopsis Tinsley and P. stelli (Brain) have been taken at U. S. ports-of-entry including: P. alleni McKenzie (Mexico, on Artemisia); P. avenae Borchsenius (Turkey, on Stachys); P. azaleae Kuwana (Japan, on azalea); P. graminicola Leonardi (New Zealand, on Feijoa); P. hurdi McKenzie (Mexico, on Dendranthema and Capsicum); P. indicus Avasthi & Shafee (Thailand, on Euphorbia); P. multicerarii Granara de Willink (Mexico, on unknown host); P. manihoti Matile-Ferrero (Central Africa and South America, on Manihot); P. nephelii Takahashi (Thailand, on Garcinia; Vietnam, on Nephelium); P. pergandei Cockerell (Japan and Korea, on Diospyros, Magnolia, Malus, Prunus, Punica, and Rhododendron); and P. persimplex Borchsenius (Kazakhstan, on Malus).