Both sexes fully winged. Body pale brown with red internal pigment; forewings uniformly shaded; antennae pale brown with segments IV–VI yellow at base; tarsi and apices of tibiae yellow. Head wider than long, finely sculptured between ocelli; ocellar setae pair III long and fluted, arising close to anterior margins of ocellar triangle. Antennae 8-segmented; segments III–IV with small forked sensorium, segment VI inner margin with long sensorium arising at some distance from base. Pronotum with narrow transverse reticulation and many markings between the main striae, discal setae weakly spatulate, posterior margin with two pairs of setae and one pair of longer posteroangular setae. Metanotum with closely spaced longitudinal striae, median pair of setae far distant from anterior margin. Forewing first vein with two widely spaced setae on distal half, second vein without setae; wing apex with one stout seta; cilia arise ventrally near anterior margin. Tergites with median pair of setae longer than distance between their bases; sculpture on lateral thirds with short longitudinal lines giving appearance of microtrichia; posterior margin of VIII with complete comb; tergite X with no longitudinal split.
The genus Pseudodendrothrips includes 17 described species, but the significance of some of the species in which the body colour is mainly yellow remains conjectural (Mound & Tree, 2007). P. alexei is recognisable because the forewings are uniformly shaded, rather than pale or banded, and the ocellar setae are unusually stout. Specimens from Australia have been studied of one or more unidentified species of Pseudodendrothrips that have dark forewings but with the base pale.
Eastern Australia (or possibly S.E. Asia)
Breeding on leaves
Maclura cochinchinesis (Moraceae)