Assessment of Hemicheyletia wellsina (Acari: Cheyletidae) as a Potential Predator for Biological Control of Arthropod Pests on Orchids

Hemicheyletia wellsina was found living on orchids in a greenhouse in association with several orchid pests. Little research on predators of plant-feeding mites in this family has been published, and there is none on this species. Because no information on its biology is available, studies to evaluate this species as a possible natural enemy in a pest-management program for orchids is justified.

            Because there is much variation in biologyamong species in the family Cheyletidae, the mode of reproduction, sex ratio of the progeny, longevity, and fecundity were studied using Tetranychus urticae, the two-spotted spider mite, as prey. All are important factors in determining if H. wellsina could be an efficient predator. The feeding method of this mite was assessed as well, because cheyletids are known to both actively search for prey as well as use an ambush method.

            In addition, a DNA sequence was obtained from H. wellsina from the mitochondrial cytochrome c oxidase 1 or “CO1” gene region using high fidelity PCR in order to submit to the Barcode of Life Database. Photographs of slide-mounted life stages were used to identify the setal patterns of each stage, as well as differences between the sexes. These morphological characteristics and DNA sequence will be useful for identification of H. wellsina specimens.