Taxonomic placing: Acari, Prostigmata
Common name: Gall mites; bud mites, rust mites, blister mites
Morphology: Eriophyids are minute mites (0.15-0.35 mm long) with elongate, annulate, worm-like bodies, two pairs of anteriorly placed legs and, close behind them, a transverse genital aperture. The prodorsal shield bears 2 pairs of or none. The tarsi lack claws but bear a feather-shaped empodium, commonly called featherclaw. The chelicerae are stylettiform. About 3,400 species in more than 250 genera have so far been named.
Life history: All Eriophyidae feed on plants and most are highly specific to their hosts (and at times even to particular organs or sites). They have a foreshortened life cycle, consisting of egg, larva, nymph and adults, a cycle often requiring less than one week. Reproduction is mostly by arrhenotoky. Males deposit spermatophores that the females locate (probably due by an unidentified pheromone) and insert into their bodies. Some species, especially those living on evergreens, have a heteromorphic female form, the deutogyne, which conserves the species during harsh (usually cold) seasons. Deutogynes breed only in the year following their own genesis, when they give rise to protogynes, the homeomorphic females, which reproduce in the same year.
Eriophyids are often dispersed by winds, the females moving to exposed sites and positioning themselves against the wind. Single wind-borne females can then establish new colonies. Dispersal also takes place on infested plant material and (more seldom) on animals.
Economic importance: The Eriophyidae include major plant pests such as the citrus rust mite, Phyllocoptruta oleivora and the tomato russet mite, Aculops lycopersici. They cause various kinds of damage; their common names derive from the specific injury. They induce gall formation, russetting, plant stunting, brooming and leaf rolling; some injuries are due to injected toxins, others to wounding the epidermal layer. In addition, some eriophyids transmit plant viruses. In severe cases these mites can totally destroy the crop, or seriously reduce its economic value.
Eriophyid pests included in this compendium
Acalitus phloeocoptes (plum tree bud mite).
Aceria mangiferae (mango bud mite).
Aceria oleae (olive gall mite).
Aceria sheldoni (citrus bud mite).
Aceria tosichella (wheat curl mite).
Aceria tulipae (ry bulb mite).
Aculops lycopersici (tomato russet mite).
Aculus cornutus (silver peach mite).
Aculus schlechtendali (apple rust mite).
Colomerus vitis (grape erineum mite).
Phyllocoptruta oleivora (citrus rust mite).
Amrine, J.W. Jr. 1996. Keys to the World Genera of the Eriophyoidea (Acari: Prostigmata). Indira Publishing House, West Bloomfield.
Amrine J.W. Jr. & Stasny, T.A. 1994. Catalog of the Eriophyoidea (Acarina: Prostigmata) of the World. Indira Publishing House, West Bloomfield.
Baker, E.W., Kono, T., Amrine, J.W. Jr., Delfinado-Baker, M. & Stasny, T.A. 1996. Eriophyoid Mites of the United States. Indira Publishing House, West Bloomfield.
Evesl, D., de Lillo, E., Monfreda, R. and Çobanoğlu, S. 2015. Eriophyoid mite fauna (Acari: Trombidiformes: Eriophyoidea) of Turkey: New species, new distribution reports and an updated catalogue. Zootaxa 3991: 1-63.
Lindquist, E.E., Sabelis, M.W. & Bruin, J. (Eds.) 1996. Eriophyoid Mites, Their Biology, Natural Enemies and Control. Elsevier, Amsterdam, pp. 790.
Navia, D., Ochoa, R., Welbourn, C. and Ferragut, F. 2010. Adventive eriophyoid mites: a global review of their impact, pathways, prevention and challenges. Experimental and Applied Acarology 51: 225–255.
Ueckermann, E.A. 2010 (Ed.). Eriophyoid mites: progress and prognoses. Experimental and Applied Acarology 51: 1-307.