Acaridae

Tyrophagus putrescentiae

Rhizoglyphus echinopus

Sancassania sp.

The Acaridae are a family of mites in order Sarcoptiformes.^[1]

Distribution

There are several acarid genera with cosmopolitan distributions, such as Acarus^[2], Sancassania^[3] and Tyrophagus.^[4] There are even Tyrophagus found in Antarctica and (spacecraft in) low Earth orbit.^[4]

Ecology

Acaridae live in various habitats and have various diets.

Many are generalists that live in natural (e.g. soil, litter, animal nests, decomposing plant material) and artificial (e.g. human dwellings, granaries, greenhouses, plant nurseries) environments. They feed on decomposing organic material, fungi and nematodes.^[2][3][4]

There are also more specialised acarids. Some Acarus inhabit nests of warm-blooded animals, mostly rodents and birds.^[2] Within Sancassania, there are species associated with certain bees, associated with scarabaeid beetles (riding phoretically on live beetles and feeding on dead beetles) or feeding on mushrooms.^[3] A lineage of Tyrophagus, comprising T. formicetorum and related species, only occurs in ant nests.^[4] A number of Histiogaster species live beneath bark (subcortical) and feed on fungi.^[5]

Dispersal

Various Acaridae have a phoretic deutonymph stage in their life cycle, a non-feeding nymph stage that can disperse to new habitats by riding on larger animals.^[2][3][4][5] Hyperphoresy (riding an animal which is itself riding a third animal) has also been reported, with acarid deutonymphs on a larger Uropodidae mite which in turn was on a beetle.^[6]

Most Tyrophagus species do not form deutonymphs (except for the T. formicetorum lineage), instead dispersing as feeding life stages. They may disperse phoretically, by active movements or by air currents.^[4]

Pests

Some Acaridae species are stored product pests, such as Acarus siro, A. farris, Tyrophagus putrescentiae, Tyrophagus longior and Tyrolichus casei. These infest stored organic materials such as grains, flour, dried fruit, milk products, hams, cheeses, straw, animal hides, invertebrate culture media, vertebrate bedding materials and animal feed. They thrive in humid conditions and on damp materials. Acaridae can cause dermatitis via piercing human skin (in attempts to feed) or via contact allergens.^[7]

There are also Acaridae which are pests of living plants. These include the genus Rhizoglyphus (pests of plants with bulbs)^[8] and the species T. longior (pest of some ornamental plants).^[9]

Genera

References