Agistemus fleschneri (Summers)
Zetzellia mali (Ewing)
Agistemus fleschneri is the principal species found in QC and northern ON orchards, while Zetzellia mali predominates in the US, southern ON and the maritime provinces. Immature stages are bright yellow. Adult females of Agistemus are orange-red (A) and can be confused with the European red mite (Panonychus ulmi), but do not possess its silky white hairs. Zetzellia adults are bright yellow (B), but can appear reddish after feeding on red mites (C). Eggs are round and yellow (D).
Note: In general, these mites are sensitive to broad-spectrum insecticides, but less so than phytoseiid mites.
Along with phytoseiids, stigmaeid mites are the most abundant predatory mites in apple orchards in this region; they feed on the eggs and larval forms of apple rust mite and European red mite, among others. It should not be confused with the yellow spider mite, Eotetranychus carpini borealis (Ewing), which is a pest of brambles but can occur on tree fruit.
Note: In combination with either the phytoseiid mites or other mite predators, these species contribute to maintaining pest mite populations below economic levels.
The MSU IPM Program maintains this site as an access point to pest management information at MSU. The IPM Program is administered within the Department of Entomology, fueled by research from the AgBioResearch, delivered to citizens through MSU Extension, and proud to be a part of Project GREEEN.