Predatory Mites

General Description

The western predator mite (Galendromus occidentalis) and other phytoseiid mites are able to provide biological control of plant-feeding spider mites and many rust mites when populations are not disrupted by harmful pesticides.  


All stages of plant-feeding mites.



Egg - Western predatory mite eggs are shiny, oval, translucent, larger than the round spider mite eggs; Z. mali eggs are round, lemon yellow, smaller than spider mite egg.

Adult - Western predatory mite is pear-shaped, translucent body that varies in colour from cream to amber depending on what they have fed on. Z. mali is wedge-shaped, bright yellow to reddish and smaller than western predatory mite (Fig.1). Both species move faster than their prey.








Figure 1. Adult Z. mali (left), western predatory mite (centre) and European red mite. (AA-FC)

Life History

Overwinter as adults on or near fruit trees. Become active in spring and produce several generations per summer depending on temperature. Both species rely on rust mites as prey in the spring until European red mites and spider mites become available.


Visual inspection of leaves or leaf brushing for microscopic examination.