Tetranychoidea

Features of Linotetranus amiculus, from Meyer & Ueckermann (1997).

Belongs within: Eleutherengonides.
Contains: Tetranychinae, Bryobiinae, Tenuipalpidae, Tuckerella.

The Tetranychoidea is a group of small plant-feeding mites, including the spider mites (Tetranychidae) and related tax. Members of this group are characterised by the modification of the chelicerae into elongate, retractable stylets that form a single hollow tube when protruded, allowing the mite to penetrate the outer cortex of its host plant. Some species of tetranychoids are significant crop pests.

The spider mites of the Tetranychidae receive their vernacular name from their production of silk webbing from unicellular glands on the palpi. They are otherwise characterised by the presence of one or two long, slender, tapered solenidia on tarsi I and II that are often closely associated with a small or minute seta to form duplex sets (Walter et al. 2009). The small family groups Linotetranidae and Allochaetophora include relatively slender mites associated with the crowns and roots of grasses and sedges. Species of Allochaetophora have three pairs of setae on the prodorsum and two pairs of eyes; Linotetranidae have four pairs of setae on the prodorsum and lack eyes (Walter et al. 2009). Only two species of Allochaetophora are known to date, the Californian A. californica and the South African A. africana. Within Linotetranidae, the South African species Anoplopalpus inunguis has a reduced palpal setation with three phaneres (two eupathidia and one seta) on the palptarsus and no claw on the palptibia. Afrolinotus dictynus, also described from South Africa, has four phaneres on the palptarsus and lacks setae d1 and e1 on the opisthosoma (Meyer & Ueckermann 1997).

Characters (from Meyer & Ueckermann 1997): Cheliceral bases fused to form a stylophore that is movable independently of the subcapitulum and can be retracted into the prodorsum; movable cheliceral digits styletlike, greatly elongated and strongly recurved basally within the stylophore, thus allowing for a greater degree of retraction and protraction, forming a single hollow probe; a pair of well-developed peritremes are embedded on the anterior portion of the prodorsum, where they end in somewhat protuberant enlargements; true claws of the legs equipped with tenent hairs, or chaetoids; males provided with aedeagal structures for direct sperm transfer.

<==Tetranychoidea
    |--Tetranychidae [Tetranycides] MU97
    |    |  i. s.: ‘Allonychus’ Pritchard & Baker 1955 non Zaitzev 1905 H98
    |    |           `--A. braziliensis (McGregor 1950) [=Septanychus braziliensis] H98
    |    |         Anatetranychus Womersley 1940 [incl. Drepanonychus Davis 1969] H98
    |    |           |--A. hakea Womersley 1940 [=Neotetranychus hakea] H98
    |    |           `--A. hapsis (Davis 1969) [=Drepanonychus hapsis, Depranonychus (l. c.) hapsis] H98
    |    |         Neotetranychus Trägårdh 1915 H98
    |    |           `--N. victoriae Davis 1969 H98
    |    |         Notonychus Davis 1969 H98
    |    |           `--N. asper Davis 1969 H98
    |    |         Tenuicrus Womersley 1940 H98
    |    |           `--T. errabundus Womersley 1940 H98
    |    |         Tylonychus Miller 1966 H98
    |    |           `--T. tasmaniensis Miller 1966 H98
    |    |         Paraponychus corderoi OA96
    |    |--Tetranychinae BT72
    |    `--Bryobiinae BT72
    `--+--Tenuipalpidae MU97
       |--Tuckerella MU97
       |--Allochaetophora McGregor 1950 [Allochaetophoridae] MU97
       |    |--*A. californica McGregor 1950 MU97
       |    `--A. africana Meyer & Ueckermann 1997 MU97
       `--Linotetranidae MU97
            |--Austrolinus Beard & Walter 2004 WL09
            |--Afrolinotus Meyer & Ueckermann 1997 MU97
            |    `--*A. dictynus Meyer & Ueckermann 1997 MU97
            |--Anoplopalpus Meyer & Ueckermann 1997 MU97
            |    `--*A. inunguis Meyer & Ueckermann 1997 MU97
            `--Linotetranus Berlese 1910 MU97
                 |--*L. cylindricus Berlese 1910 MU97
                 |--L. achrous Baker & Pritchard 1953 MU97
                 |--L. amiculus Meyer & Ueckermann 1997 MU97
                 |--L. annae Meyer & Ueckermann 1997 MU97
                 |--L. edenvillensis Meyer & Ueckermann 1997 MU97
                 |--L. protractulus Athias-Henriot 1961 MU97
                 `--L. ramosus Meyer & Ueckermann 1997 MU97

*Type species of generic name indicated

REFERENCES

[BT72] Baker, E. W., & D. M. Tuttle. 1972. New species and further notes on the Tetranychoidea mostly from the southwestern United States (Acarina: Tetranychidae and Tenuipalpidae). Smithsonian Contributions to Zoology 116: 1–37.

[H98] Halliday, R. B. 1998. Mites of Australia: A checklist and bibliography. CSIRO Publishing: Collingwood.

[MU97] Meyer, M. K. P. S., & E. A. Ueckermann. 1997. A review of some species of the families Allochaetophoridae, Linotetranidae and Tuckerellidae (Acari: Tetranychoidea). International Journal of Acarology 23 (2): 67–92.

[OA96] Ochoa, R., H. Aguilar, G. Evans & C. Vargas. 1996. Knowledge of phytophagous mites (Prostigmata) of Central America. In: Mitchell, R., D. J. Horn, G. R. Needham & W. C. Welbourn (eds) Acarology IX vol. 1. Proceedings pp. 181–184. Ohio Biological Survey: Columbus (Ohio).

[WL09] Walter, D. E., E. E. Lindquist, I. M. Smith, D. R. Cook & G. W. Krantz. 2009. Order Trombidiformes. In: Krantz, G. W., & D. E. Walter (eds) A Manual of Acarology 3^rd ed. pp. 233–420. Texas Tech University Press.

Last updated: 23 June 2022.