Female macroptera. Body and legs mainly yellow, abdominal segment X dark brown, lateral margins of IX shaded light brown; antennal segments I–III yellow, IV–VIII dark brown; fore wing weakly shaded in basal half. Antennae 8-segmented, segment I with no dorso-apical setae, sensoria on III–IV simple. Head broadest across eyes, cheeks straight, converging to base, anterior margin projecting conically in front of eyes; compound eyes with 5 pigmented facets; ocellar setae pair I far apart; III small and arising between mid-points of posterior ocelli; maxillary palps 2-segmented. Pronotum weakly trapezoidal, posterior margin with 4 pairs of setae, 2 pairs of sub-equal posteroangular setae. Prosternal basantra granulate, with 2 pairs of setae; fernal plates scarcely connected medially; meso and meta furca without spinula. Mesonotal anterior campaniform sensilla present, median pair of setae distant from posterior margin. Metanotum medially with irregular sculpture; median setae just behind anterior margin, closer to lateral pair than to each other; no campaniform sensilla. Fore wing slender, first vein with 6–8 setae on basal half, 3 widely spaced setae on distal half; second vein with about 5 widely spaced setae; clavus with 4 or 5 veinal setae but no discal seta; posterior fringe wavy. Tergal sculpture weak but complete medially; II–VIII with broad craspedum, campaniform sensilla close to posterior margin; tergites V–VIII with few microtrichia laterally; setal pair S2 on VIII no longer than S1; tergite IX with median dorsal setae extending well beyond posterior margin of tergite, subequal to posterior median setae in length and thickness; X longer than IX, with complete split. Sternites with no marginal craspedum, II with 0–3 discal setae, 2 pairs of marginal setae; III–VII with irregular row of about 5–7 discal setae; VII with no submarginal setae.
Male not known.
The genus Masimithrips comprises six species, all from northern Australia. These share most character states with the species of Monothrips, but have only two maxillary palp segments and lack sternal craspeda.Aliceathrips species lack setae on the prosternal basantra, and have the head different in shape, and the species of Caprithrips are all wingless and have no long pronotal setae. Females of williei are unique within the genus in having antennal segments IV–V uniformly dark brown.
Known only from Australia
Western Australia, Queensland.
Feeding and breeding on leaves
Native grasses (Poaceae).
Masamithrips williei Mound
Mound LA. 2011. Grass-dependent Thysanoptera of the family Thripidae from Australia. Zootaxa 3064: 1–40. http://www.mapress.com/zootaxa/2011/f/zt03064p040.pdf