In life, adult female elongate, bluntly pointed at anterior and posterior ends, slightly convex, whitish just after final moult and becoming deep brown at maturity.
Slide-mounted specimens up to about 5.0 mm long and 1-2 mm wide. Dorsum with small round areolations present. Antennae gently tapering, 160-200 µm long, each with number of segments reduced to 3 or 4. Legs showing reduction, shorter than antennae; tibia and tarsus fused, often without any sign of division. Anal plates each with lateral angle rounded and with antero lateral edge shorter than postero-lateral edge. Stigmatic setae present in a group at base of each small spiracular cleft, each group consisting of 1 median blunt seta and 2 lateral blunt conical setae, each lateral seta up to 1/4 length of median seta. Marginal setae short, bluntly pointed. Eyes submarginal, each surrounded by an oval clear area.Dorsal surface with spine-like setae present, varying considerably in shape from cylindrical to conical, with bluntly pointed or rounded apices. Minute pores, each with a slender duct, scattered, each associated with an areolation. Preopercular pores present on midline of abdomen only. Smaller discoidal pores present, scattered. Submarginal tubercles present, numbering about 8 on each side of body.
Ventral surface with short pointed setae present; long pointed setae present on 3 segments anterior to vulvar region and between antennae. Multilocular disc pores, each often with 7 loculi, few: present in vulvar region only and extending to 1 or 2 anterior abdominal segments. Quinquelocular pores present in more or less single rows in stigmatic furrows. Minute oval pores scattered. Tubular ducts absent.Biology
Generally infests the underside of leaves, taking position alongside the leaf vein (Zimmerman, 1948, Gill et al., 1977).
Structure
Adult female elongate, pointed at anterior and posterior ends, slightly convex; colour of young female creamy-white, while older ones are brown to blackish brown (Gill et al., 1977). See colour photograph in Kawai (1980, Fig. 6.14), Hamon & Williams (1984), Wong et al. (1999).
General Remarks
Good description and illustration of adult female by Zimmerman (1948), Gill et al. (1977), Tao et al. (1983), Hamon & Williams (1984), Williams & Watson (1990) and by Tang (1991).
Keys Tang 1991: 76 (female); Williams & Watson 1990: 82 (female); Hamon & Williams 1984: 38 (female); Tao et al. 1983: 63 (female); Kawai 1980: 141-142 (female); Zimmerman 1948: 293 (female).