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Fig. 1. Oligonychus tiwakae adult female paratype - detail of claws I and IV.

Fig. 2. Oligonychus tiwakae adult female paratypes - detail of pregenital striae; and detail of claws I-IV.

Fig. 3. Oligonychus tiwakae adult female paratype - detail of pattern of pregenital striae (at different focal points).

Fig. 4. Oligonychus tiwakae adult female paratype - detail of pattern of prodorsal striae.

Fig. 5. Oligonychus tiwakae adult male paratypes - detail of claws I and IV.

Fig. 6. Oligonychus tiwakae adult male paratype - detail of peritreme tip (same individual, different sides).

Fig. 7. Oligonychus tiwakae adult male paratypes - detail of aedeagus (at different focal points); and detail of claws I-IV.

Fig. 8. Oligonychus tiwakae adult male paratype - detail of aedeagus (at different focal points).

Fig. 9. Oligonychus tiwakae adult male paratype - detail of aedeagus.

Fig. 10. Oligonychus tiwakae adult male paratype - detail of aedeagus (at different focal points).

Fig. 11. Oligonychus tiwakae adult male (non-types) - detail of aedeagus (at different focal points); and detail of claw I.

Material examined

types; non-types

Taxonomy

Subfamily Tetranychinae

Tribe Tetranychini

Distribution

+Australia, *New Caledonia

Taxonomy Changes

None

Diagnosis

Female

• empodia I-IV = long slender claw, longer than proximoventral hairs (Figs 1, 2)
• pregential striae mostly transverse to weakly arching around genital flap, but can have patches of irregular striae just anterior to genital flap (Figs 2, 3)
• prodorsal striae longitudinal, forming a U-shaped posteriorly (Fig. 4)
• dorsal opisthosomal striae transverse
• peritreme ending in slightly expanded bulbous tip (Fig. ) 
• tarsus I with the sockets of four tactile setae proximal to, and one solenidion overlapping, the socket of the proximal duplex seta
• tarsus II with the sockets of two tactile setae and one solenidion proximal to, and two tactile setae overlapping, the socket of the duplex seta
• tibiae I-IV 10(1+0), 6, 5, 6
• green with three dark spots dorsally

Male

• empodium I = short stout, strongly curved dorsal claw; ventral claw directed ventrally, short tapered; dorsal claw slightly longer than or subequal to ventral claw (Figs 5, 7, 11)
• empodia II-IV with strong curved claw, subequal in length with proximoventral hairs (Figs 5, 7)
• peritreme ending in simple bulb, slightly expanded (Fig. 6)
• tarsus I with the sockets of four tactile and two solenidia proximal to, and one solenidion overlapping, the socket of the proximal duplex seta
• tarsus II with sockets of two tactile setae and one solenidion proximal to, and two tactile setae overlapping, the socket of the duplex seta
• chaetotaxy for legs I-IV:
  • femora 10, 7, 4, 4
  • genua 5, 5, 4, 4
  • tibiae 12(3+0), 6, 5, 6
• aedeagus dorsally directed; short stout neck, with small knob; anterior projection short broad triangular, and posterior projection short fine triangular; dorsal margin of knob angulate; dorsal margin of shaft parallel to ventral margin; dorsal angle right-angled (Figs 7-11) 
• yellow

Hosts

Imperata cylindrica, *Themeda sp. (Poaceae)

Similar Taxa

Oligonychus ephamnus Beard & Walter 2003

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

*Gutierrez, J. (1978)  Cinq nouvelles especes de Tetranychidae (Acariens) de Nouvelle-Caledonie.  Acarologia 20: 351-364

+Gutierrez, J. and Schicha, E. (1983)  The spider mite family Tetranychidae (Acari) in New South Wales.  International Journal of Acarology 9: 99-116