Head & thorax
Head & pronotum
Meso & metanota
Female fully winged. Body dark brown, tarsi and apices of tibiae yellow; fore wing brown with base pale. Antennae 8-segmented, III & IV each with apex narrowed and bearing a long forked sense cone. Head wider than long, with 2 pairs of ocellar setae, Pair III anterolateral to ocellar triangle. Pronotum with strong transverse lines of sculpture, with no long setae. Metanotum with distinctive transverse lines of sculpture, median setae arising behind anterior margin. Fore wing first vein with 2 setae distally, second vein with at least 15 setae. Tergites without sculpture medially, but lateral thirds with many closely spaced transverse lines; VIII with regular comb of long microtrichia; X without longitudinal split. Sternite VII with 2 pairs of median setae arising well in front of posterior margin.
Male fully winged; tergite IX without stout setae; sternites III–VII each with a pair of pore plates.
Dichromothrips includes 18 species from orchids in the Old World tropics. An identification key to 14 of these is given by Mound (1976), and Okajima (1999) provides information on four species from Borneo. D. corbetti differs from the other members of the genus in having no elongate posteroangular setae on the pronotum, whereas the other species have either one or two pairs of such setae. The genus is possibly related to Taeniothrips, in which the species breed mainly on leaves.
Breeding on leaves and in flowers of various cultivated Orchidaceae, and causing scarring on flowers of Vanda spp.
Originally from southeast Asia, but recorded widely around the world; likely to be imported to California, or intercepted in quarantine.
THRIPIDAE - THRIPINAE
Dichromothrips corbetti (Priesner)
Anaphothrips corbetti Priesner, 1936: 209
Mound LA (1976) Thysanoptera of the genus Dichromothrips on Old World Orchidaceae. Biological Journal of the Linnean Society 8: 245–265.
Okajima S (1999) On four Dichromothrips species (Thysanoptera, Thripidae) collected from one population of Arundina sp. (Orchidaceae) in Sabah, Borneo. Japanese Journal of Systematic Entomology 5: 145–152.