Acalitus adoratus

The eriophyid mite Acalitus adoratus Keifer was first collected from Chromolaena (Eupatorium) odorata (L.) King and Robinson (Asteraceae) (Acari: Eriophyidae) in Trinidad in 1968, and described from these specimens (Keifer 1970). The specific name adoratus derives from a misreading of the specific name of the plant on the hand-written specimen label. A. adoratus has also been found on C. odorata in Florida and is probably widespread in the native range of C. odorata in the Neotropics. 

The mite causes abnormal growth of the epidermal hairs on young leaves and stems. The resulting tangled masses of thickened and deformed hairs are called "erineum patches" and are visible without magnification as whitish patches 1-4 mm in dia, usually on the leaf underside and often accompanied by a convexity of the upper leaf surface. The mites, 0.14-0.18 mm long, live within the erineum patches protected by the abnormally dense hair growth. The damage caused to the plant is usually slight, but heavy attack can cause deformation and stunting of both leaves and stems (Cruttwell 1977). 

The Accidental Introduction of the Chromolaena Mite, Acalitus adoratus, Into South-East Asia