Phytoseiidae

The Phytoseiidae are a family of mites which feed on thrips and other mite species. They are often used as a biological control agent for managing mite pests. Because of their usefulness as biological control agents, interest in Phytoseiidae has steadily increased over the past century. Public awareness of the biological control potential of invertebrates has been growing, though mainly in the US and Europe. In 1950, there were 34 known species. Today, there are 2,731 documented species organized in 90 genera and three subfamilies. The family Phytoseiidae contains these subfamilies: Amblyseiinae Muma, 1961 Phytoseiinae Berlese, 1916 Typhlodrominae Scheuten, 1857 Phytoseiid eggs can be found along the vein of the bottom side of a leaf. They are oblong and translucent white. The larvae of these mites range from translucent white to tan in colour. They are tiny and oval in shape and size, have six legs, and are wingless. Nymphs look similar to larvae, with the exception of being slightly larger and having eight legs. Adult phytoseiids are less than 0.5 mm in size, pear-shaped, wingless, and have eight legs. They are translucent white, but turn a pale tan, orange/red, or green after feeding. Developmental rate is species-specific, ranging from less than a week to four weeks, with temperature and diet affecting the rate. The body of Phytoseiidae is divided into two parts: the gnathosoma (anterior) and idiosoma (posterior). The gnathosoma includes chelicerae, sensorial palps, and a stylophore. Males have an added feature- a spermatodactyl to transfer spermatophore to females. Phytoseiid mites are best known as predators of small arthropods and nematodes, but many species are also known to feed on fungi, plant exudates, and pollen. Scientists have proposed classifications of the Phytoseiidae based on their food sources. In the most current version, developed in 2013, phytoseiids are grouped into four types. Type I includes species that are specialized mite predators, with three subgroups determined by the type of prey.