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Fig. 1. Tetranychus yusti adult female paralectotype - detail of empodia.

Fig. 2. Tetranychus yusti adult female paralectotype - detail of pattern of pregenital striae.

Fig. 3. Tetranychus yusti adult female paralectotype - detail of peritreme (arrows indicate hook).

Fig. 4. Tetranychus yusti adult female paralectotype - detail of pattern of prodorsal striae.

Fig. 5. Tetranychus yusti adult female paralectotype - detail of pattern of dorsal striae between setae e1 and f1.

Fig. 6. Tetranychus yusti adult female paralectotype - detail of pattern of ventral striae between setae 3a and 4a (note lobes present on striae as far anterior as setae 3a).

Fig. 7. Tetranychus yusti adult male lectotype - detail of empodium IV (arrow indicates minute dorsal spur).

Fig. 8. Tetranychus yusti adult male lectotype - detail of aedeagus (at different focal points).

Fig. 9. Tetranychus yusti adult male lectotype - detail of aedeagus (at different focal points).

Material examined

lectotype, paralectotype

Taxonomy

Subfamily Tetranychinae

Tribe Tetranychini

Common Name

none

Distribution

^^NOT PRESENT IN AUSTRALIA

Brazil, Cape Verde Islands, Colombia, Cook Islands, *Ecuador, El Salvador, French Polynesia, Greece, Honduras, Mexico, Nigeria, Thailand, USA, Venezuela

Taxonomy Changes

none

Diagnosis

Female

• empodia I-IV with no 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 anteriomedially, striae are entire laterally and posteriorly but pattern appears weak medially (Fig. 2)
• peritreme hook moderately long (Fig. 3)
• prodorsal striae fine, longitudinal forming a rounded U-shape posteriorly (Fig. 4)
• dorsal striae between setae e1-f1 forming the diamond pattern - i.e. straie between e1-e1 longitudinal, between e1-f1 transverse, between f1-f1 longitudinal (Fig. 5)
• ventral striae with small lobes as far anterior as setae 3a (Fig. 6)

Male

• empodia I-IV with obvious dorsal spur above proximoventral hairs (Fig. 7)
• empodia I with proximoventral hairs fused to form ventral claw
• peritreme with moderately long hook
• aedeagus dorsally directed, with short narrow neck and distinct knob; anterior projection, rounded, semicircular; posterior projection short sharp triangular; dorsal margin of knob flat to weakly concave medially; dorsal margin of shaft at 50-60° angle to ventral margin, abruptly bent dorsad at right angle and recurved anteriorly to form rounded anterior projection (Figs 8, 9)

Hosts

> 40 host species including: Cassia sp. (Fabaceae), Colocasia sp. (Araceae), Fragaria sp. (Rosaceae), *Gossypium sp. (Malvaceae), Ipomoea batatas (Convolvulaceae), Manihot esculenta (Euphorbiaceae), Passiflora sp. (Passifloraceae), Plumeria sp. (Apocynaceae), Zea mays (Poaceae)

References

*McGregor, E.A. (1955) Notes on the spider mites (Tetranychidae) of Ecuador.  Revista Ecuatoriana de Entomologia y Parasitologia 2(3/4): 365-377

Migeon, A. and Dorkeld, F. (2006-2017) Spider Mites Web: a comprehensive database for the Tetranychidae. http://www.montpellier.inra.fr/CBGP/spmweb

Notes

Male specimen in poor condition, and many details, including thoses of tarsus I and II, are not visible. 

^^ of concern to Australia; on economic hosts in southeast Asia