Williams, D.J., & Matile-Ferrero, D. 2005a Mealybugs from Zanzibar and Pemba islands with a discussion of a potential invasive species (Hemiptera, Pseudococcidae).. Revue Française d'Entomologie 27(4): 145-152.

Notes: This paper provides a list of mealybug species known from Zanzibar and Pemba islands based on specimens in The Natural History Museum, London, and from published records. Trionymus longipilosus (a possible invasive species) is here redescribed and transferred to the genus Crisicoccus. Formicococcus cocotis sp. nov. is described from Zanzibar on coconut. Some species described in the genus Eurycoccus from Africa and neighbouring areas are transferred to Crisicoccus, and all African species formerly included in the genus Planococcoides are transferred to Formicococcus. The name Planococcoides lamabokensis is here synonymized with Planococcoides njalensis syn. nov. and transferred herein to Formicococcus.