Parasitiformes
Holothyrans, ticks and mesostigmatic mites
David Evans Walter
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close boxIntroduction
The Parasitiformes is one of the three major lineages of chelicerate arthropods that are called mites. Ticks are among the most economically important parasitiform mites, but numerous Mesostigmata, especially in the Dermanyssoidea are also debilitating parasites of mammals, birds, and reptiles. The phytoseiid mites used in biological control belong to the Mesostigmata, as do numerous species of predators that inhabit soil-litter systems. Currently, both the Ixodida (ticks) and Holothyrida consist of three families; the Mesostigmata contains approximately 70 family-level taxa.
Characteristics
Parasitiform mites have free coxae, a ventral anal opening covered by a pair of plates, corniculli on the hypostome (lost in ticks), a sclerotised ring surrounding the gnathosoma (capitulum), and usually a biflagellate tritosternum (lost in ticks, many holothyrids, and some parasitic Mesostigmata).
Discussion of Phylogenetic Relationships
The hypothesis by Lehtinen (1991) supports a sistergroup relationship between Holothyrida and Ixodida; however, other acarologists have suggested that ticks and Mesostigmata are sistergroups. Phylogenetic analyses addressing the proper placement of ticks are underway in Queensland and Ohio.
References
Lehtinen, P.T. 1991. Phylogeny and zoogeography of the Holothyrida. In: Dusabek, F. and Bukva, V. (eds.) Modern Acarology, Volume 2. SPB Academic Publishers, The Hague, pp. 101-113.
Title Illustrations
SEM of Allothyrus sp. from Queensland (D.E. Walter)
| Scientific Name | Allothyrus sp. |
|---|---|
| Location | Queensland |
| Image Use |
 This media file is licensed under the Creative Commons Attribution-NonCommercial License - Version 3.0.
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| Copyright |
© 1996
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About This Page
University of Alberta, Edmonton, Alberta, Canada
Correspondence regarding this page should be directed to David Evans Walter at
Page copyright © 1996
Page: Tree of Life
Parasitiformes. Holothyrans, ticks and mesostigmatic mites.
Authored by
David Evans Walter.
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- First online 13 December 1996
- Content changed 13 December 1996
Citing this page:
Walter, David Evans. 1996. Parasitiformes. Holothyrans, ticks and mesostigmatic mites. Version 13 December 1996 (under construction). http://tolweb.org/Parasitiformes/2566/1996.12.13 in The Tree of Life Web Project, http://tolweb.org/
