Watson, G.W., Williams, D.J., von Ellenrieder, N., & Kinnee, S.A. 2017 Evidence for a cryptic species-group around Phenacoccus madeirensis Green, 1923 (Hemiptera: Pseudococcidae). The Pan-Pacific Entomologist 93(3):115–126
Notes: The Madeira mealybug, Phenacoccus madeirensis Green, 1923 (Hemiptera: Coccomorpha: Pseudococcidae) is a highly polyphagous, invasive pest species that is actively extending its geographical range. There has been some uncertainty as to how to separate it reliably from a less invasive species, P. gossypii Townsend & Cockerell, 1898, due to the occurrence of intermediate morphologies. In this study, molecular and morphological analysis of Phenacoccus mealybugs intercepted on fresh plant material entering California provided evidence that there is a complex of undescribed cryptic species around P. madeirensis.