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Fig. 1.  Tetranychus lintearius - adult female, empodium I

Fig. 2.  T. lintearius - adult female, tarsus I

Fig. 3.  T. lintearius - adult female, pregenital striae

Fig. 4.  T. lintearius - adult female, peritreme

Fig. 5.  T. lintearius - adult female, pattern of dorsal striae = diamond

Fig. 6.  T. lintearius - adult male, empodium I

Fig. 7.  T. lintearius - adult male, empodium II

Fig. 8. T. lintearius - adult male, aedeagus

Material examined

non-types

Taxonomy

Subfamily Tetranychinae

Tribe Tetranychini

Common Name

Gorse spider mite

Distribution

+Australia (Tasmania), Algeria, Belgium, *France, Hawaii, Italy, New Zealand, Portugal, Spain, UK

Taxonomy Changes

Tetranychus linearicus Dufour 1832

Tetranychus ulicis Jordain, synonymy Andre 1933

Tetranychus linearicus Oudemans 1937 [sic]

Tetranychus lintearius van Eyndhoven 1967 (re-established species)

Diagnosis

Female

• empodia I-IV with obvious dorsal spur (4 long) (Fig. 1) 
• tarsus I with the sockets of four tactile setae proximal to, and one solenidion overlapping, the socket of the proximal duplex seta (Fig. 2)
• pregenital striae longitudinal, sometime irregular anteriorly (Fig. 3)
• peritreme hook moderately long (Fig. 4) 
• dorsal striae between setae e1-f1 not forming a diamond (= "hourglass") - striae between e1-e1 transverse, e1-f1 transverse, f1-f1 longitudinal, or irregular oblique (Fig. 5)
• summer form without lobes on dorsal and ventral striae

Male

• empodia I-IV with obvious dorsal spur above proximoventral hairs (4-5 long) (Figs 6, 7)
• empodia I and II both with proximoventral hairs fused to form a ventral claw (Figs 6, 7)
• aedeagus dorsally directed with very short neck and small knob; anterior projection of knob absent; posterior projection of knob short broad truncate triangular; dorsal margin of knob flat to weakly convex; dorsal margin of shaft at approx 20° angle to ventral margin, abruptly bending dorsally at right angle to form knob (Fig. 8)

Hosts

Calicotome villosa, *Ulex europaeus, U. nanus, U. parviflorus (Fabaceae)

References

*Dufour, L. (1832)  Description et figure du Tetranychus linearicus, Arachnide nouvelle de la tribu des Acarides.  Ann. Sci. Nat. Paris 25: 276

+Ireson, J.E., Gourlay, A.H., Kwong, R.M., Holloway, R.J. and Chatterton, W.S. (1999)  Progress on the rearing, release and establishment of the gorse spider mite, Tetranychus lintearius Dufour, for the biological control of gorse in Australia.  pp. 320-324.  In: Proceedings of the XIIth Australian Weeds Conference, 12-16 September 1999, Hobart, Tasmania. (Eds A.C. Bishop, Boersma, M. and Barnes, C.D.)

Migeon, A. and Dorkeld, F. (2006-2017) Spider Mites Web: a comprehensive database for the Tetranychidae. http://www.montpellier.inra.fr/CBGP/spmweb