Female macroptera. Body yellow with brown markings medially on tergites and sternites, also on head anterior to ocelli; compound eyes with no ommatidia strongly pigmented; antecostal ridges on tergites III–VIII dark across full width of segments, on sternites IV–VII strongly shaded; fore wings weakly shaded; antennal segment I pale, II dark, III pale with apex shaded, IV–V darker with base pale, VI–VIII uniformly dark. Head about twice as wide as long, postocular and ocellar region closely striate; ocellar setae pair III arise within ocellar triangle, distance between their bases about equal to diameter of first ocellus; three pairs of post-ocellar setae at least as long as ocellar setae pair III. Pronotum closely striate, 5 pairs of posteromarginal setae, pairs I–III all approximately equal in length and thickness but S2 sometimes longer than S1. Metanotum transversely striate anteriorly, longitudinally reticulate posteriorly; median pair of setae at anterior margin. Fore wing clavus with 3–4 marginal setae; first vein setae 3–11+1–8+1-2+0–1; second vein with 5–7 setae; posteromarginal fringe cilia straight. Tergites III–V with bases of median setae usually separated <0.75 length of these setae; tergal microtrichial fields with 3 discal setae; VIII with discal microtrichia present anteromedially, posteromarginal comb interrupted medially; tergite IX with discal microtrichia absent or very weak. Sternites with lateral microtrichial fields weak, not extending mesad of marginal setae S2; median setae on sternites IV – VI sometimes arising slightly in front of posterior margin.
Male macroptera. Similar to female in colour and sculpture, but smaller; tergite VIII posteromarginal comb interrupted medially; segment IX without drepanae, anterior margin strongly convex, extending into segment VII; aedeagus with paired array of stout spines.
The genus Scirtothrips comprises over 100 described species worldwide, with 21 species known from Australia most of which are endemics to this continent. These species all have the lateral thirds of the abdominal tergites covered in closely spaced rows of fine microtrichia, and in many species the sternites also bear similar microtrichia. The antennae are 8-segmented, except in S. casuarinae and S. solus, both forewing veins have an irregular and incomplete setal row, and a median spinula is present on both the meso and metafurca. S. eremicus exhibits a confusing pattern of character states,and possibly represents a species-group that is widely distributed across northern Australia just south of the monsoon belt, presumably in association with one or more species of Acacia.
Known only from Australia.
Queensland, Western Australia.
Feeding and breeding on young phyllodes.
Various Acacia spp (Mimosaceae).
Scirtothrips eremicus Hoddle & Mound
Hoddle MS & Mound LA. 2003. The genus Scirtothrips in Australia (Insecta, Thysanoptera, Thripidae). Zootaxa 268: 1-40. http://www.mapress.com/zootaxa/2003f/zt00268.pdf