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Fig. 1. Tetranychus piercei adult female (non-type; The Philippines) - detail of minute dorsal spur on empodia (indicated by arrows).
Fig. 2. Tetranychus piercei adult female (non-type; The Philippines) - detail of the pattern of pregenital striae = longitudinal with broken striae anteromesally (note that the pattern can become weaker mesally).
Fig. 3. Tetranychus piercei adult female (non-type; The Philippines) - detail of the pattern of pregenital striae = longitudinal with broken striae anteromesally (note that the pattern can become weaker mesally).
Fig. 4. Tetranychus piercei adult female (non-type; The Philippines) - detail of the pattern of pregenital striae = longitudinal with broken striae anteromesally (note that the pattern can become weaker mesally).
Fig. 5. Tetranychus piercei adult female (non-type; The Philippines) - detail of the pattern of pregenital striae = longitudinal with broken striae anteriorly (note that the pattern can become weaker mesally).
Fig. 6. Tetranychus piercei adult female (non-type; The Philippines) - detail of peritreme.
Fig. 7. Tetranychus piercei adult female (non-type; The Philippines) - detail of peritreme (indicated by arrows).
Fig. 8. Tetranychus piercei adult female (non-type; The Philippines) - detail of the pattern of prodorsal striae (n.b. striae pattern rounded U-shape posteriorly).
Fig. 9. Tetranychus piercei adult female (non-type; The Philippines) - detail of the pattern of prodorsal striae (n.b. striae pattern squared U-shape posteriorly).
Fig. 10. Tetranychus piercei adult female (non-type; The Philippines) - detail of the pattern of dorsal striae between setae e1 and f1 (classic diamond shape = e1-e1 longitudinal, e1-f1 transverse, f1-f1 longitudinal).
Fig. 11. Tetranychus piercei adult female (non-type; The Philippines) - detail of the pattern of dorsal striae between setae e1 and f1 (= classic diamond shape); note that striae between e1-e1 are oblique to longitudinal.
Fig. 12. Tetranychus piercei adult female (non-type; The Philippines) - detail of the pattern of dorsal striae between setae e1 and f1 (classic diamond shape = e1-e1 longitudinal, e1-f1 transverse, f1-f1 longitudinal).
Fig. 13. Tetranychus piercei adult female (non-type; The Philippines) - detail of the pattern of dorsal striae between setae e1 and f1 (= diamond shape); note that striae between e1-e1 are mixed oblique to longitudinal.
Fig. 14. Tetranychus piercei adult male (non-type; The Philippines) - detail of minute dorsal spur on empodia (indicated by arrows).
Fig. 15. Tetranychus piercei adult male holotype - detail of peritreme (indicated by arrow).
Fig. 16. Tetranychus piercei adult male holotype - detail of pattern of striae on prodorsum (mostly lateral aspect).
Fig. 17. Tetranychus piercei adult male holotype - detail of aedeagus (at different focal points). Note that it is difficult to determine the shape of the dorsal projection, and the interpretation of its shape changes with the focus point.
Fig. 18. Tetranychus piercei adult male holotype - detail of aedeagus (at different focal points). Note that it is difficult to determine the shape of the dorsal projection, and the interpretation of its shape changes with the focus point.
Fig. 19. Tetranychus piercei adult males (non-types) - detail of aedeagus (at different focal points). Note that it is difficult to determine the shape of the dorsal projection, and the interpretation of its shape changes with the focus point. Specimens from the type country The Philippines and from Papua New Guinea.
Fig. 20. Tetranychus piercei adult male (non-type; The Philippines) - detail of aedeagus; same individual as #2 in Fig. 19 (n.b. aedeagus is not flat - shape distorted).
Material examined
holotype; non-types from The Philippines
Taxonomy
Subfamily Tetranychinae
Tribe Tetranychini
Common Name
none
Distribution
++Australia, *The Philippines
Taxonomy Changes
none
Diagnosis
Female
empodia I-IV with minute dorsal spur above the proximoventral hairs (Fig. 1) 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 three tactile setae and one solenidion proximal to, and three tactile setae overlapping, the socket of the duplex seta
pregenital striae longitudinal and broken anteromedially, entire laterally, pattern can be weak medially (Figs 2-5) peritreme hook long (Figs 6, 7) prodorsal striae fine, longitudinal with small lobes, forming a rounded U-shape (Fig. 8) or a squared U-shape posteriorly (Fig. 9) dorsal striae between setae e1-f1 forming the diamond pattern - i.e. straie between e1-e1 longitudinal (Figs 10-12) or irregular (Fig. 13), between e1-f1 transverse, between f1-f1 longitudinal (Figs 10-13)- ventral striae with small lobes between genital region and setae 4a
Male
empodia I-IV with obvious dorsal spur above proximoventral hairs (Fig. 14) empodia I with proximoventral hairs fused to form ventral claw (Fig. 14) tarsus I with the sockets of four tactile setae and two solenidia proximal to, and socket of one solenidion overlapping, the socket of the proximal duplex seta tarsus II with sockets of three tactile setae and one solenidion proximal to, and three tactile setae overlapping, the socket of the duplex seta peritreme with long hook (Fig. 15) prodorsum with longitudinal striae forming a U-shape posteriorly; lobes absent (Fig. 16) aedeagus: it is very difficult to determine the accurate shape of the very tip of the aedeagus of the holotype, and it appears to range from truncate to curved finger:
Holotype: aedeagus dorsally directed, with short abruptly tapering neck, without knob; no anterior or posterior projection; dorsal margin of shaft at 5-10° angle to ventral margin, gently curving ventrally before abruptly bent dorsal at right angle to form short abruptly tapered finger-like dorsal projection; extreme tip of dorsal projection appears truncate at one focal point, tapered at different focal point or direcged posteriorly at another focal point (Fig. 17). Non-type: extreme tip of dorsal projection with a minute anterior and posterior projection on a minute truncate anvil-shaped knob (Fig. 19: Philippines 1, PNG 2, 3); at different focal point, extreme tip appears finger-like and directed posteriorly (Fig. 19: Philippines 2, PNG 1, 3; Fig. 20).
Hosts
This species has been recorded on more than 80 host species, including many Convolvulaceae, Cucurbitaceae, Euphorbiaceae and Fabaceae.
The type host is *Clitoria ternatea (Fabaceae).
References
Migeon, A. and Dorkeld, F. (2006-2017) Spider Mites Web: a comprehensive database for the Tetranychidae. http://www.montpellier.inra.fr/CBGP/spmweb
*McGregor, E.A. (1950) Mites of the family Tetranychidae. American Midland Naturalist 44: 257-420
Notes
++ Specimens identified as Tetranychus piercei have been collected from several islands in the Torres Straight from as early as 1983 on cassava, Manihot esculenta (Euphorbiaceae) (specimens in Queensland Musuem).
There is a range of variation in the shape of the aedeagus in non-type specimens identified as T. piercei.
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