Corroboreethrips, a new genus of minute apterous thrips (Insecta : Thysanoptera : Phlaeothripinae) from the bark of Australian Acacia trees

Abstract

Six new species are described in the new genus Corroboreethrips: C. kallus, sp. nov., C. siagonus, sp. nov., C. stomius, sp. nov., C. subsolanus, sp. nov., C. suspectus, sp. nov. and C. zophus, sp. nov. They all live in cavities beneath thin, split bark of slender branches on particular Acacia tree species in arid parts of Australia, and two species-pairs show a vicariant distribution between Queensland and Western Australia. In life, adults of these minute black, wingless thrips are remarkable in appearance, decorated with irregular rows of tiny white dots, the product of numerous short, stout dorsal setae coated with a white waxy substance. The structure of the antennae of these species is unique within the Phlaeothripidae, with segments VII and VIII short and forming a small style that is closely joined to segment VI, segment III produced basally into a sleeve around the pedicel, and segment II strongly asymmetric. The mouth cone varies in length among the six species more than in any other known thrips genus. In two species it is relatively short, extending to the fore coxae, but in two others it extends as far as the hind coxae and is thus relatively longer than in any other phlaeothripid.