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Fig. 1. Oligonychus festucolus adult female - detail of empodium I (top) & IV.

Fig. 2. O. festucolus adult female paratype - detail of claw I.

Fig. 3. O. festucolus adult female paratype - detail of claw II.

Fig. 4. O. festucolus adult female paratype, detail of: a. claw III; b. claw IV.

Fig. 5. O. festucolus adult female - detail of pattern of pregenital striae.

Fig. 6. O. festucolus adult female paratype - detail of pregenital striae.

Fig. 7. O. festucolus adult female paratype - detail of pregenital striae.

Fig. 8. O. festucolus adult female paratype - detail of pregenital striae.

Fig. 9. O. festucolus adult female paratype - detail of pregenital striae.

Fig. 10. O. festucolus adult female - detail of peritreme.

Fig. 11. O. festucolus adult female - detail of patterns of dorsal striae between setae f1 and f2.

Fig. 12. O. festucolus adult female paratype - detail of pattern of striae between dorsal setae f1 and f2.

Fig. 13. O. festucolus adult female paratype - detail of pattern of striae on the prodorsum (n.b. U-shaped striae begins between setae sc1).

Fig. 14. O. festucolus adult male paratype - detail of pattern of striae on the prodorsum (n.b. U-shaped striae begins between setae sc1).

Fig. 15. O. festucolus adult male - detail of empodium I (top) & IV.

Fig. 16. Oligonychus festucolus adult male holotype - a. detail of aedeagus (at different focal points, from upper to lower); b. detail of upper and lower focal points combined; c. detail of claw I.

Fig. 17. Oligonychus festucolus adult male holotype - a-d detail of aedeagus at different focal points, from to lower to upper.

Material examined

types

Taxonomy

Subfamily Tetranychinae

Tribe Tetranychini

Distribution

*Australia: Kimberley Region, north Western Australia

Taxonomy Changes

None

Diagnosis

Female

• empodia I-IV = curved claw, subequal in length to proximoventral hairs (Figs 1-4) 
• tarsus I with the sockets of three/four tactile setae and one solenidion proximal to, and one tactile seta overlapping, the socket of the proximal duplex seta
• pregenital striae mostly transverse to weakly arching around genital flap, and often with irregular patches of oblique and longitudinal striae (Figs 5-9
• peritreme ending in slightly expanded tip (Figs 10, 14)
• dorsal striae mostly transverse, except sometimes with wavy and oblique striae between setae f1 and f2 (Figs 11, 12) 
• striae on prodorsal forming distinct U-shape (Figs 13, 14)
• spinneret of palp short, broad, one and half times longer than wide
• chaetotaxy for legs I-IV:
  • femora 10, 6, 4, 4
  • genua 5, 5, 4, 4
  • tibiae 10(1+0), 6, 5, 6
• pale green with white legs often with green tinge, dark green to black food spots on either side of body

Male

• empodium I = bifid claw, dorsal and ventral claws equal in length (Fig. 15)
• empodia II-IV with dorsal claw strongly curved, almost equal length to proximoventral hairs (Fig. 15) 
• tarsus I with the sockets of four tactile and two solenidia proximal to the socket of the proximal duplex seta
• peritreme ending in simple bulb, slightly expanded (Fig. 10) 
• spinneret of palp twice as long as wide  
• chaetotaxy for legs I-IV:
  • femora 10, 6, 4, 4
  • genua 5, 5, 4, 4
  • tibiae 12(3+0), 6, 5, 6
• aedeagus dorsally directed; shape of knob varies through different focal points (see below); dorsal margin of knob angulate, varying from broad angle (Figs 16a, 17c,d) to right angle (Figs 16c, 17a); anterior projection of knob short triangular; neck obviously narrower than knob; dorsal angle of shaft acute, narrowly rounded
  • upper focus (Figs 16a, 17c,d) - posterior projection short broad triangular, dorsal margin
  • mid focus (Fig. 16b) - posterior projection short and truncate
  • lower focus (Figs 16c, 17a) - posterior projection short, narrow triangle
• pale green with yellow tinge, darker green food spots dorsally, and legs yellow.

Hosts

*Arundinella nepalense (Poaceae)

Similar Taxa

Oligonychus tiwakae Gutierrez 1978

References

*Beard, J.J., Walter, D.E. and Allsopp, P.G. (2003)  Spider mites of sugarcane in Australia: a review of grass-feeding Oligonychus Berlese (Acari: Prostigmata: Tetranychidae).  Australian Journal of Entomology 42: 71-78