Mites are small arachnids. Mites span two large orders of arachnids, the Acariformes and the Parasitiformes, which were historically grouped together in the subclass Acari. However, most recent genetic analyses do not recover the two as each other's closest relative within Arachnida, rendering the group non-monophyletic. Most mites are tiny, less than 1 mm (0.04 in) in length, and have a simple, unsegmented body plan. The small size of most species makes them easily overlooked; some species live in water, many live in soil as decomposers, others live on plants, sometimes creating galls, while others are predators or parasites. This last type includes the commercially destructive Varroa parasite of honey bees, as well as scabies mites of humans. Most species are harmless to humans, but a few are associated with allergies or may transmit diseases.
Abacarus hystrix, the cereal rust mite or grain rust mite, belongs to the family Eriophyidae. They are extremely small with adults measuring up to 1 millimetre in length and only have four legs at the front of the body. Viewing by the human eye requires a 10 – 20X lens. The adult mites are usually yellow but also have been seen to be white or orange. The cereal rust mite was first found on Elymus repens, a very common perennial grass species. It has now been found on more than 60 grass species including oats, barley, wheat and ryegrass, found in Europe, North America, South Africa and Australia. Mites migrate primarily through wind movement and are usually found on the highest basal sections of the top two leaf blades. Abacarus hystrix produces up to twenty overlapping generations per year in South Australian perennial pastures, indicating that the species breeds quite rapidly. It has been noted that the cereal rust mite can cause losses in yield of up to 30-70%.
Wheat streak mosaic virus (WSMV) is a plant pathogenic virus of the family Potyviridae that infects plants in the family Poaceae, especially wheat ; it is globally distributed and vectored by the wheat curl mite, particularly in regions where wheat is widely grown. First described in Nebraska in 1922, stunted growth and the eponymous “streaks” of yellowed, non-uniform discoloration are characteristic of WSMV infection. As it has been known to cause 100% crop mortality, WSMV is a subject of ongoing scientific research.
Eriophyoidea are a superfamily of herbivorous mites. All post-embryonic instars lack the third and fourth pairs of legs, and the respiratory system is also absent.
Aceria is a genus of mites belonging to the family Eriophyidae, the gall mites. These tiny animals are parasites of plants. Several species can cause blistering and galls, including erineum galls. A few are economically significant pests, while others are useful as agents of biological pest control of invasive plants such as rush skeletonweed, creeping thistle, and field bindweed.
Aceria guerreronis, the coconut mite, is an eriophyid mite which infests coconut plantations. It is economically devastating, and can destroy up to 60% of coconut production. The immature nuts are infested and injured by mites feeding in the portion covered by the perianth of the immature nut.
Floracarus perrepae is a species of herbivorous mite belonging to the family Eriophyidae. It is native to Australia (Queensland), China and New Caledonia. As it is known to attack and eat the invasive fern species Lygodium microphyllum, it is being considered for use as a biological pest control agent in Florida.
Aceria anthocoptes, also known as the russet mite, rust mite, thistle mite or the Canada thistle mite, is a species of mite that belongs to the family Eriophyidae. It was first described by Alfred Nalepa in 1892.
Acalitus is a genus of mites in the family Eriophyidae. These cosmopolitan, microscopic arthropods form galls on various plants, and some species such as Acalitus essigi and Acalitus vaccinii are pests of agricultural significance associated with berry crops. This genus includes the following species:
Aceria clianthi is a species of mite belonging to the family Eriophyidae. It is found only in New Zealand. It is notable for being host specific to threatened plants of the genus Clianthus. It is classified by Buckley et al. as "nationally critical" under the New Zealand Threat Classification System. They stated "Aceria clianthi (Eriophyidae), has been recorded only from kakabeak in cultivation and once on Lotus cornalatus [Lotus corniculatus] (Fabaceae), an introduced plant growing near kakabeak. It is given the same threat classification as kakabeak ." Heenan had earlier stated that "the two species [of Clianthus] are considered to be threatened, with C. maximus having a rank of vulnerable, whereas C. puniceus is critically endangered", but the conservation status of C. maximus was subsequently found to be more serious. These threat classifications for Clianthus apply to plants in the wild, but the species are widely cultivated. Aceria clianthi occurs on both plants in the wild and in cultivation.
Brevipalpus phoenicis, also known as the false spider mite, red and black flat mite, and in Australia as the passionvine mite, is a species of mite in the family Tenuipalpidae. This species occurs globally, and is a serious pest to such crops as citrus, tea, papaya, guava and coffee, and can heavily damage numerous other crops. They are unique in having haploid females, a condition caused by a bacterium that change haploid males into females.
Schinopsis brasiliensis is a species of flowering plant in the cashew family known by the common names baraúna or braúna.
High plains disease is a viral disease afflicting wheat and maize. It is caused by the negative-sense ssRNA virus High Plains wheat mosaic emaravirus. Symptoms are similar to Wheat streak mosaic virus, with leaf veins showing yellow flecks and streaks, followed by leaf margin purpling in maize. Depending on the timing of infection, stunting and death occur. Plants can be doubly infected with high plains virus and wheat streak mosaic virus.
High Plains wheat mosaic emaravirus (WMoV), or High Plains virus (HPV) or Maize red stripe virus (MRSV/MRStV) is the causative agent of High plains disease of maize and wheat. It is spread by wheat curl mite, Aceria tosichella, which also transmits Wheat streak mosaic virus. The mite's ability to transmit a number of different viruses to cereal crops make it an economically important agricultural pest. In late June 2017 this virus was first detected in Canada, in Alberta. The Alberta samples were 99% similar to those in the USA. As Wheat streak mosaic virus is already present in Alberta, and coinfection with these two causes even more severe damage, this could cause much higher yield losses.
Poacevirus is a genus of viruses, in the family Potyviridae. Poaceae plants serve as natural hosts. There are three species in this genus.
Eriophyes tulipae, commonly known as the dry bulb mite, is a species of mite in the genus Eriophyes. This mite feeds on members of the lily family, and has damaged garlic crops. At one time, it was also thought to feed on wheat and other grasses, but the wheat curl mite is now regarded as a different species, Aceria tosichella.
Magdalena Kathrina Petronella Smith Meyer was a South African acarologist who was regarded as a world authority on plant-feeding mites of agricultural importance and was known as the "mother of red-spider mites of the world". She described more than 700 new species and 25 new genera, mostly of mites of agricultural importance. Meyer was involved in the promotion of biological control of mites using predatory mites, spiders and insects.
Pycnocomon is a genus of flowering plants belonging to the family Caprifoliaceae. They were formerly placed in the defunct family of Dipsacaceae.
Aleuroglyphus ovatus, commonly known as brown-legged mite or brownlegged grain mite, is a species of mite in the family Acaridae. It is a cosmopolitan pest of grain.
Nalepella, the rust mites, is a genus of very small Trombidiform mites in the family Phytoptidae. They are commonly found on a variety of conifers, including hemlock, spruce, balsam fir, and pine. They sometimes infest Christmas trees in nurseries. Nalepella mites are vagrants, meaning they circulate around the tree; females overwinter in bark cracks. Infested spruce emit a characteristic odour.
