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Fig. 1. Schizotetranychus gahniae adult female - dorsal habitus.
Fig. 2. S. gahniae adult female - detail of gnathosoma (arrow indicates elongate palp).
Fig. 3. S. gahniae adult female - detail of pattern of pregenital striae.
Fig. 4. S. gahniae adult female - detail of tarsus I, indicating number of proximal setae (s = solenidion).
Fig. 5. S. gahniae adult female - detail of tarsus II.
Fig. 6. S. gahniae adult male - lateral habitus.
Fig. 7. S. gahniae adult male - dorsal habitus (note elongate gnathosoma).
Fig. 8. S. gahniae adult male - detail of tarsus I, indicating number of proximal setae (d = duplex setae; s = solenidion).
Fig. 9. S. gahniae adult male - detail of tarsus I, indicating number of proximal setae (d = duplex setae; s = solenidion).
Fig. 10. S. gahniae adult male - detail of aedeagus (dorsal aspect).
Fig. 11. S. gahniae adult male, aedeagus - detail of aedeagus (image on left indicates outline of aedeagus).
Material examined
types; non-types
Taxonomy
Subfamily Tetranychinae
Tribe Tetranychini
Common Name
None
Distribution
*Australia: eastern Queensland
Taxonomy Changes
None
Diagnosis
Female
- gnathosoma elongate, reaching to distal end of tibia I, with palps a little longer than rostrum (Figs 1, 2)
- stylophore nearly three times as long as wide
- pregenital striae fine, transverse, arching around genital flap (Fig. 3)
- peritreme strongly recurved = strong distal hook
- dorsal opisthosomal striae transverse
- lobes on dorsal striae small, triangular to semi-circular
- tarsus I with the sockets of four tactile setae proximal to, and one solenidion proximal to or overlapping, the socket of the proximal duplex seta (Fig. 4)
- tarsus II with the sockets of three tactile setae and one solenidion proximal to, and one solendion overlapping, the socket of the duplex seta (Fig. 5)
- tibiae I-IV 9(1+0), 8, 6, 7
- yellow-green with dark lateral spots
- eggs globular to slightly oval fixed to leaf surface, often in rows
Male
- gnathosoma elongate as in female (Figs 6, 7)
- tarsus I with the sockets of four tactile and two solenidia proximal to, and one solenidion overlapping, the socket of the proximal duplex seta (Figs 8, 9)
- tarsus II with sockets of one-two tactile setae and two solenidia proximal to, and one tactile seta overlapping, the socket of the duplex seta
- peritreme recurved = ending in distal hook
- tibiae I-IV 11-12(2-3+0), 8, 7, 7
- aedeagus essentially straight with dorsal margin of shaft downturned sharply about 2/3 along length creating a distal narrowing of shaft to form short truncate tip (Figs 10, 11)
Hosts
*Gahnia aspera (Cyperaceae)
Similar Taxa
Similar to Schizotetranychus cynodonis Mc Gregor and Schizotetranychus parasemus Pritchard & Baker, except S. gahniae has empodia lacking proximoventral hairs, a hooked peritreme, differing leg chaetotaxy and a differently shaped aedeagus (Davis 1969).
Biology
The mites are found on the ventral surface of the leaf blades, in small colonies each protected by its own closely woven silken cover or sheet of webbing. Eggs are laid in single file, in rows of up to 16 (pers. obs.) and are individually covered in a silken patch.
References
*Davis, J.J. (1969b) A new species of Schizotetranychus (Acarina: Tetranychidae) from Queensland. Journal of the Australian Entomological Society 8: 107-109
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