Parasitiformes are a superorder of

Arachnid Arachnida () is a class of joint-legged invertebrate animals (arthropods), in the subphylum Chelicerata. Arachnida includes, among others, spiders, scorpions, ticks, mites, pseudoscorpions, harvestmen, camel spiders, whip spiders and vinegar ...

s, constituting one of the two major groups of mites, alongside

Acariformes The Acariformes, also known as the Actinotrichida, are the most diverse of the two superorders of mites. Over 32,000 described species are found in 351 families, with an estimated total of 440,000 to 929,000 species, including undescribed specie ...

. Parasitiformes has, at times, been classified at the rank of order or suborder. It is uncertain whether Parasitiformes and Acariformes are closely related, and in many analyses they are recovered more closely related to other arachnids. Amongst the best known members of the group are the

tick Ticks (order Ixodida) are parasitic arachnids that are part of the mite superorder Parasitiformes. Adult ticks are approximately 3 to 5 mm in length depending on age, sex, species, and "fullness". Ticks are external parasites, living by ...

s, though the

Mesostigmata Mesostigmata is an order of mites belonging to the Parasitiformes. They are by far the largest group of Parasitiformes, with over 8,000 species in 130 families. Mesostigmata includes parasitic as well as free-living and predatory forms. They can ...

is by far the most diverse group with over 8,000 described species, including economically important species such as the

varroa mite ''Varroa destructor'', the ''Varroa'' mite is an external parasitic mite that attacks and feeds on the honey bees '' Apis cerana'' and ''Apis mellifera''. The disease caused by the mites is called varroosis. The ''Varroa'' mite can reproduce o ...

Description

Taxonomy

Holothyrida The Holothyrida are a small order of mites in the superorder Parasitiformes. No fossils are known. With body lengths of more than they are relatively large mites, with a heavily sclerotized body. It is divided into three families, Allothyridae, ...

- small group of scavenging mites native to former Gondwana landmasses *

Ixodida Ticks (order Ixodida) are parasitic arachnids that are part of the mite superorder Parasitiformes. Adult ticks are approximately 3 to 5 mm in length depending on age, sex, species, and "fullness". Ticks are external parasites, living by ...

– ticks *

– a large order of predatory and parasitic mites *

Opilioacarida Opilioacaridae is the sole family of mites in the order Opilioacarida, made up of about 13 genera. The mites of this family are rare, large (1.5 to 2.5 mm) mites, and are widely considered primitive, as they retain six pairs of eyes, and a ...

– a small group of large, long-legged segmented mites. Many species are parasitic (most famous of which are

s), but not all. For example, about half of the 10,000 known species in the suborder

are

predatory Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...

and

cryptozoa ''Cryptozoa'' is the collective name for small animals who live in darkness and under conditions of high relative humidity, as in the wet soil underneath rocks, decomposing tree bark etc. Examples include pseudoscorpions, slugs, centipedes and ear ...

n, living in soil-litter, rotting wood, dung, carrion, nests or house dust. A few species have switched to grazing on

fungi A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from ...

or ingesting spores or pollen. Phylogenetic relationships of the groups, after Klompen, 2010: The phytoseiid mites, which account for about 15% of all described Mesostigmata are used with great success for

biological control Biological control or biocontrol is a method of controlling pests, such as insects, mites, weeds, and plant diseases, using other organisms. It relies on predation, parasitism, herbivory, or other natural mechanisms, but typically also i ...

. There are over 12,000 described species of Parasitiformes, and the total estimate is between 100,000 and 200,000 species.

Gallery

Evolutionary history

The oldest known fossils of Parasitiformes, representing three out of the four modern groups, Ixodida, Mesostigmata, and Opilioacarida, are known from Cretaceous aged

amber Amber is fossilized tree resin that has been appreciated for its color and natural beauty since Neolithic times. Much valued from antiquity to the present as a gemstone, amber is made into a variety of decorative objects."Amber" (2004). In ...

, dating to around 100 million years ago. They are suspected to have diversified substantially earlier. The genetic divergence between the groups is less than that of Acariform mites, suggesting a younger origin, likely dating to the late

Paleozoic The Paleozoic (or Palaeozoic) Era is the earliest of three geologic eras of the Phanerozoic Eon. The name ''Paleozoic'' ( ;) was coined by the British geologist Adam Sedgwick in 1838 by combining the Greek words ''palaiós'' (, "old") and ' ...

References

Arachnid orders {{Acari-stub