Predatory mite

Amblyseius swirskii

Amblyseius swirskii is a small, pear-shaped predatory mite, the adults of which are about 0.4mm long (males being slightly smaller than females). Like most predatory mites, A swirskii has five life stages: egg, larva, protonymph, deutonmyph and adult. The larval stage is very pale in colour and has three pairs of legs, whereas the protonymph, deutonymph and adult stages all have four pairs of legs. The older stages are generally darker than the larvae, but colour can vary with diet: when feeding on whiteflies, they are typically yellowish to pale tan.

Amblyseius swirskii is a generalist predator which will feed on a Wide variety of prey, including various species and stages of thrips and mites, as well as the eggs and Young nymphs of both greenhouse whitefly (T. vaporariorum) and sweet potato whitefly (B. tabaci).
When prey is scarce, these mites can also survive and reproduce on pollen from various plants (including eggplant and bell pepper). Amblyseius swirskii is typically found amongst its prey on the underside of leaves, aften laying its eggs at the intersection of the main vein and lateral veins, or in similar protected areas.

This species can complete its development at temperatures between 18 to 35°C (64 to 95°F), but performs best when temperatures are above 25°C (77°F). At this temperature, the life-cycle can be completed in approximately S days. It is important to note, however, that humidity plays an important role in its population growth: relative humidity should be at or above for optimal egg development and hatching. This mite is not known to
enter diapause, and can be used for much of the growing season provided that day-time temperatures are consistently above 22°C (72°F).