The Acari are a taxon of arachnids that contains mites and ticks. The diversity of the Acari is extraordinary and their fossil history goes back to at least the early Devonian period. Acarologists have proposed a complex set of taxonomic ranks to classify mites. In most modern treatments, the Acari are considered a subclass of the Arachnida and are composed of two or three superorders or orders: Acariformes, Parasitiformes, and Opilioacariformes; the latter is often considered a subgroup within the Parasitiformes. The monophyly of the Acari is open to debate, and the relationships of the acarines to other arachnids is not at all clear. In older treatments, the subgroups of the Acarina were placed at order rank, but as their own subdivisions have become better understood, treating them at the superorder rank is more usual.
The tangor is a citrus fruit hybrid of the mandarin orange and the sweet orange. The name "tangor" is a formation from the "tang" of tangerine and the "or" of "orange". Also called the temple orange, its thick rind is easy to peel and its bright orange pulp is sour-sweet and full-flavoured.
Eriophyidae is a family of more than 200 genera of mites, which live as plant parasites, commonly causing galls or other damage to the plant tissues and hence known as gall mites. About 3,600 species have been described, but this is probably less than 10% of the actual number existing in this poorly researched family. They are microscopic mites and are yellow to pinkish white to purplish in color. The mites are worm like, and have only two pairs of legs. Their primary method of population spread is by wind. They affect a wide range of plants, and several are major pest species causing substantial economic damage to crops. Some species, however, are used as biological agents to control weeds and invasive plant species.
The peacock mites of the genus Tuckerella are a significant herbivorous pest in the tropics, for example on citrus fruit. Other species dwell in grasses, possibly as root feeders.
Dioxathion, systematically known as p-dioxane-2,3-diyl ethyl phosphorodithioate, is an organophosphate pesticide. It is used as an insecticide on livestock and as an acaricide on citrus fruits, deciduous fruits and nuts.
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%.
Panonychus ulmi, the European red mite, is a species of mite which is a major agricultural pest of fruit trees. It has a high reproductive rate, a short generation time and produces many broods in a year, all of which contribute to its pest status. It has a cosmopolitan distribution, and a very wide host range, having been found on the following plants:
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 sheldoni, commonly called the citrus bud mite, is a species of mite belonging to the family Eriophyidae. It feeds in leaf- and flower-buds of Citrus spp., causing deformation to leaves, flowers and fruit, and is a worldwide pest of citrus fruit production.
Lorryia formosa, commonly known as the yellow mite or the citrus yellow mite, is a species of acariform mite. They are in the subfamily Tydeinae of the family Tydeidae. Commonly found on the foliage of citrus trees around the world, Lorryia formosa also associates with a variety of other plant types. The life cycle includes six discrete stages of development, and the lifespan averages about 37 days. The females of the species use an asexual form of reproduction where the growth and development of embryos occurs without fertilization by a male, a process called thelytoky.
Trombiculosis, is a rash caused by trombiculid which is often referred to as a chigger bite.
Eriophyes is a genus of acari that forms galls, specially on trees of the family Rosaceae. Some are called blister mites. The blue butterfly Celastrina serotina has been reported to feed on these galls and also on the mites, making it one of the uncommon carnivorous Lepidoptera.
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.
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.
Brevipalpus is a genus of mites in the family Tenuipalpidae, the flat mites. The genus includes several species that are among the most important economic pests in the flat mite family.
Cilevirus is a genus of viruses in the family Kitaviridae. Plants serve as natural hosts. There are two species: Citrus leprosis virus C and Citrus leprosis virus C2.
Citrus black spot is a fungal disease caused by Guignardia citricarpa. This Ascomycete fungus affects citrus plants throughout subtropical climates, causing a reduction in both fruit quantity and quality. Symptoms include both fruit and leaf lesions, the latter being critical to inter-tree dispersal. Strict regulation and management is necessary to control this disease since there are currently no citrus varieties that are resistant.
Citrus leprosis(CL) is an economically important viral disease affecting citrus crops. This emerging disease is widely distributed in South and Central America, from Argentina to Mexico. The disease is associated with up to three different non-systemic viruses, which cause similar symptoms in the citrus hosts and are transmitted by the same vector, mites of the genus Brevipalpus; although they have vastly different genomes. Citrus leprosis virus nuclear type (CiLV-N) is found in the nuclei and cytoplasm of infected cells, while Citrus leprosis virus cytoplasmic type (CiLV-C) is found in the endoplasmic reticulum. In 2012, a new virus causing similar symptoms was found in Colombia and it was named Citrus leprosis virus cytoplasmic type 2 (CiLV-C2) due to its close proximity to CiLV-C. The cytoplasmic type viruses are the most prevalent and widely distributed of the three species.
Typhlodromips swirskii, the Swirski mite, is a species of predatory mite in the family Phytoseiidae. It is used in biological pest control of western flower thrips in greenhouse or indoor grown crops.
Isaria fumosorosea is an entomopathogenic fungus, formerly known as Paecilomyces fumosoroseus. It shows promise as a biological pesticide with an extensive host range.
