Female macropterous. Body and legs brown, fore tarsi and apex of fore tibiae paler; antennal segment III yellow, usually only with apex brown, IV yellow in basal third, V–IX brown; forewing weakly and variably shaded, with paler areas sub-basally and sub-apically; clavus and costal vein shaded.
Head with postocular region shorter than eye length; distal maxillary palp segment subdivided. Antennae 9-segmented, III–IV with sensorium curving around apex, weakly sinuous and extending to basal half of segment, with weak discoidal internal markings. Mesonotum with 3 or 4 pairs of accessory setae medially. Metanotal reticles with rather weak internal dot-like markings (sometimes weakly linear markings). Abdominal tergite I transverse lines medially; trichobothria on X about as large as base of major setae on X. Sternites with 4 pairs of marginal setae and about 4 pairs of discal setae laterally, none medially on VII.
Male similar to female but smaller. Abdominal tergite I with two longitudinal ridges. Sternites with 1 or 2 pairs of discal setae laterally, apparently none on IX.
The genus Desmothrips is known only from Australia, with 18 described species (Pereyra & Mound, 2010). D. crespii is an unusual species within this genus because, like D. stepheni and also D. mendozai, it has the forewings more or less uniformly shaded without any discrete dark bands. There is some variation in structure between populations, in size, colour and form of the sculpture within the metanotal reticles, and this may indicate the existence of a suite of sibling species (Pereyra & Mound, 2010).
Known only from Australia
Widespread across Australia in the northern part of the arid zone, between Mt Isa in Queensland and Tom Price in Western Australia.
Collected particularly from the flowers of various species of Acacia (Mimosaceae), but also from the white flowers of a species of Hakea (Proteaceae).
Breeding in the flowers of various plants.