Females fully winged. Body brown, tarsi and apices of tibiae yellow, also antennal segments III–IV and base of V; fore wings light brown with base paler. Head about as long as wide, broadly and roundly projecting in front of eyes; 2 pairs of ocellar setae present, pair III wide apart lateral to ocellar triangle; one pair of postocular setae displaced toward posterior. Antennae 7-segmented; segments III–IV with short forked sensorium. Pronotum with little sculpture and few discal setae; 2 pairs of long posteroangular setae. Metanotum irregularly reticulate; median setae small and arising behind anterior margin; campaniform sensilla present. Fore wing first vein with 2 setae on distal half; second vein with about 12 setae. Abdominal tergites V–VIII with paired ctenidia, on VIII posteromesad to spiracle; tergites V–VI with paired campaniform sensilla close to posterior margin; tergite VIII with complete comb of relatively widely separated slender teeth. Sternites without discal setae.
Two species are described in Toxonothrips, the second being T. fuscus Post from Oregon. The genus is closely related to, and presumably derived from, the genus Thrips, but has the head prolonged in front of the eyes.
Toxonothrips gramineae Moulton
Presumably breeding on leaves rather than in florets.
Poaceae or Cyperaceae, but with no recorded specificity.