Spider mites of Australia (including key exotic southeast Asian pest species)

Top Material examined Taxonomy Common Name Distribution Taxonomy Changes Diagnosis Hosts Similar Taxa Biology References Notes

Material examined

types

Taxonomy

Subfamily Tetranychinae

Tribe Tetranychini

Common Name

None

Distribution

*Australia (NT)

Taxonomy Changes

None

Diagnosis

Female

• empodia I-IV = curved claw  (Figs 1b-4), often with minute dorsal spur visible (Figs 2, 3)
• pregenital striae longitudinal, with some oblique striae laterally (Figs 5, 6, 8c)
• tarsus I with the sockets of four tactile setae proximal to and one solenidion proximal to, or overlapping with, the socket of the proximal duplex seta (Fig. 1a)  
• tarsus II with the socket of three tactile setae and one solenidion proximal to, and one tactile seta overlapping with, the socket of the duplex seta
• peritreme ending in simple unexpanded bulb (Fig. 7)
• most dorsal striae transverse, except oblique to longitudinal, often irregular, between opisthosomal setae f1-f1 and f1-f2 (Figs 8-12)
• spinneret of palp one and half to twice as long as wide, with pointed tip 
• chaetotaxy for legs I-IV:
  • femora 10, 6, 4, 4
  • genua 5, 5, 4, 4
  • tibiae 10(1+0), 7, 6, 7
• pale green

Male

• empodium I = bifid claw, ventral and dorsal claws subequal in length; ventral claw stout, dorsal claw slender (Figs 1c, 13)
• empodia II-IV with slender dorsal claw of equal length to proximoventral hairs (Figs 1d, 13)
• peritreme ending in slightly expanded simple bulb (Fig. 7) 
• spinneret of palp twice as long as wide
• tarsus I with the sockets of four tactile and two/three solenidia proximal to the socket of the proximal duplex seta (one of the three solenidia often overlapping the duplex seta, hence two/three solenidia proximal) (Fig. 1e)
• chaetotaxy for legs I-IV:
  • femora 10, 6, 4, 4
  • genua 5, 5, 4, 4
  • tibiae 13(4+0), 7, 6, 7
• aedeagus dorsally directed, with somewhat sinuous dorsal projection; no anterior projection; dorsal projection is short straight neck that bends posteriorly to form short, weakly tapering finger-like projection; dorsal margin of shaft at 45° angle to ventral margin, abruptly bent dorsally to form an acute angle at base of dorsal projection (Figs 14-16)
• pale green with yellow tinge 

Hosts

*Musa sp. (Musaceae)

Similar Taxa

Oligonychus turbelli Beard & Walter 2003

Oligonychus sapienticolus Gupta (1976)

Biology

Mites were found in small populations on the underside of the host's leaves, mainly along the main middle vein.  Little webbing is produced and their feeding causes yellow-white speckling that turns more yellow and can be seen from the top of the leaf. 

References

*Beard, J.J. (2008) A new species of spider mite, Oligonychus palus sp. nov. (Prostigmata: Tetranychidae), from tropical Australia.  Australian Journal of Entomology 47: 102-106

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

Gupta, S.K. (1976) Contribution to our knowledge of tetranychid mites (Acarina) with descriptions of three new species from India.  Oriental Insects 10: 327-351

Notes

Length of dorsal setae c3: O. palus 80-86 micrometres, O. turbelli 68-71; solenidion in distal duplex complex: O. palus 75-78, O. turbelli 61-67; tarsus IV solenidion: O. palus 46-50, O. turbelli 38-40.