Exotic mite families

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Taxonomy

updated 2025

Common names

cryptic false spider mites

Probability of encounter

low

Quarantine importance

Low. The Linotetranidae are associated with soil and grasses around the world. None are known to be important plant pests.

Diagnosis

• Empodiumempodium:
  (pl. empodia) an unpaired structure arising between the tarsal claws, ranging from pad-like to claw-like and often bearing structures such as tenent hairs, dense setulae, or taking the form of a featherclaw (Eriophyoidea)..
  with tenent hairs
• Prodorsumprodorsum:
  the dorsal surface of the propodosoma.
  with 4 pairs of setaeseta:
  (pl. setae, from L. = bristle) cuticular process composed of a hollow shaft (sometimes filled with a refractive material) produced from a membranous socket (the alveolus); the hair-like, spine-like, branched or variously expanded structures on the surfaces of the legs and body.  Most setae function as mechanoreceptors, but others (e.g., solenidia) are chemoreceptors or have unknown or ambiguous functions.
  (vi, ve, sci, sce)
• Adult female with 3 pairs of anal setaeseta:
  (pl. setae, from L. = bristle) cuticular process composed of a hollow shaft (sometimes filled with a refractive material) produced from a membranous socket (the alveolus); the hair-like, spine-like, branched or variously expanded structures on the surfaces of the legs and body.  Most setae function as mechanoreceptors, but others (e.g., solenidia) are chemoreceptors or have unknown or ambiguous functions.
  (males with 5 pairs of ano-genital setaeseta:
  (pl. setae, from L. = bristle) cuticular process composed of a hollow shaft (sometimes filled with a refractive material) produced from a membranous socket (the alveolus); the hair-like, spine-like, branched or variously expanded structures on the surfaces of the legs and body.  Most setae function as mechanoreceptors, but others (e.g., solenidia) are chemoreceptors or have unknown or ambiguous functions.
  )
• Cheliceralcheliceral:
  of or pertaining to the chelicera.
  bases adnate, fused mesally into a stylophorestylophore:
  chelicerae formed of fused cheliceral bases bearing stylet-like movable digits as in Raphignathae (Prostigmata), e.g., the plant parasitic spider mites and their relatives (Tetranychoidea).  In predatory and parasitic Cheyletoidea and parasitic Myobiidae, the stylophore and subcapitulum are fused into a gnathosomal capsule.
  (sometimes withdrawn into the bodybody:
  the idiosoma of mites.
  ); chelicerae with fixed digitfixed digit:
  the distal extension of the middle article of the chelicera; usually bearing teeth and a distal hook and opposed to the movable digit in chelate-dentate forms, but often regressed; in Mesostigmata the fixed digit may bear the pilus dentilis.
  reduced and movable digit whiplike.
• Peritremes typically chamberedchambered:
  a structure with discrete compartments, e.g., the peritremes of some ologamasids (Mesostigmata) and prostigmatans.
  structures on the dorso-lateral surface of the prodorsumprodorsum:
  the dorsal surface of the propodosoma.
  ; naso absent; prodorsal trichobothriatrichobothrium:
  (pl. trichobothria) (= bothridial sensillum) an often elaborately modified seta set in a cup-like base; forms include filiform, ciliate, pectinate or variously thickened or clubbed (bat-like to globose or capitate).
  absent; 2 pairs of eye lenses usually present. Palps 5 segmented; usually (except Anoplopalpus) with thumbclaw process (claw-like setaseta:
  (pl. setae, from L. = bristle) cuticular process composed of a hollow shaft (sometimes filled with a refractive material) produced from a membranous socket (the alveolus); the hair-like, spine-like, branched or variously expanded structures on the surfaces of the legs and body.  Most setae function as mechanoreceptors, but others (e.g., solenidia) are chemoreceptors or have unknown or ambiguous functions.
  on the palp tibiatibia:
  (pl. tibiae) the leg segment between the genu and the tarsus.
  and a thumb- or button-like subterminal palp tarsustarsus:
  (pl. tarsi) the subdistal leg segment between the tibia and the pretarsus (apotele).
  ). Leg tarsitarsus:
  (pl. tarsi) the subdistal leg segment between the tibia and the pretarsus (apotele).
  usually with tenent hairs on claws or empodiumempodium:
  (pl. empodia) an unpaired structure arising between the tarsal claws, ranging from pad-like to claw-like and often bearing structures such as tenent hairs, dense setulae, or taking the form of a featherclaw (Eriophyoidea)..
  . Genital papillaegenital papillae:
   1-3 pairs of extrusible finger-like to button-like projections, usually retracted into in the genital vestibule of acariform mites; sometimes formed as sessile disks around the genital opening; thought to be osmoregulatory structures; modified or multiplied and dispersed over the body in many freshwater mites.  Genital papillae are absent in the larva, but may be added ontogenetically: protonymphs have one pair, deutonymphs two pairs, and tritonymphs (and adults) three pairs.  The tritonymphal pair of papillae is often lost.  The serially homologous Claparède's organ is usually present in the larvae (and prelarvae) of mites exhibiting genital papillae in nymphs and adults (Oudeman's Rule).
  absent; males with an intromittent aedeagusaedeagus:
  a male intromittent organ, especially when sclerotized (e.g., in Tetranycoidea, Raphignathoidea); a penis is a flexible, membranous intromittent organ, although 'penis' is often used for aedeagi (e.g., in Astigmata).
  .

Similar taxa

Linotetranids resemble other elongate Tetranychoidea associated with grasses such as Allochaetophoridae (which have eyes) and some Tenuipalpidae (which lack a thumbclaw process and usually have eyes).

Ecology and distribution

The Tetranychoidea are plant-associated mites, and includes the infamous spider mites (Tetranychidae). Tetranychoid species that feed on grasses or pasture legumes may occasionally appear in soil samples.

References

• Baker and Pritchard 1953Baker and Pritchard 1953:
  Baker EW, Pritchard AE. 1953. The family categories of tetranychoid mites, with a review of the new families Linotetranidae and Tuckerellidae. Annals of the Entomological Society of America 46: 243–258.
• Beard and Walter 2004Beard and Walter 2004:
  Beard JJ, Walter DE. 2004. Cryptic false spider mites: A new genus, Austrolinus, and a review of the family Linotetranidae (Acari: Prostigmata: Tetranychoidea). Invertebrate Systematics 18 (5): 593–606.
• Krantz 1978Krantz 1978:
  Krantz GW. 1978. A manual of acarology [2nd ed.]. Oregon State University Book Stores, Corvallis.
• Meyer and Ueckermann 1997Meyer and Ueckermann 1997:
  Meyer MKPS and Ueckermann EA. 1997. A review of some species of the families Allochaetophoridae, Linotetranidae and Tuckerellidae (Acari: Tetranychoidea). International Journal of Acarology 23: 67-92.