Body colour largely yellow, including legs; head brown anteromedially; abdominal segments V–VI with sub-marginal brown area on each side; antennal segments brown except the basal half of II & III and extreme bases of IV–VI; fore wings uniformly brown, paler at apex. Head with two pairs of ocellar setae; ocellar setae III long and arising close together within ocellar triangle. Antennae 8-segmented, III & IV with forked sense cones; IV long and constricted apically. Pronotum with two pairs of long posteroangular setae and several moderately long discal setae; anteroangular and anteromarginal setae not developed. Mesothoracic spinula long; metathoracic spinula absent. Metanotum weakly reticulated medially; paired campaniform sensilla present; two pairs of setae arising close to anterior margin. Tarsi 2-segmented. Fore wing with first vein bearing only few setae and second vein complete. Abdominal tergites II–VIII with minute median setae and without microtrichia; VIII without posteromarginal comb of microtrichia. Sternites without discal setae and with three pairs of long posteromarginal setae; V–VI with brown area with rough callosity on each side of sternites. Both sexes fully winged.
Male with sternites III–VII bearing transversely elongate pore plates medially and two small, oval, submarginal pore plates on each side; tergite IX with a pair of stout processes posteromedially.
Intraspecific variation
Brown area usually present on abdominal sternite IV of females.
Genus and similar species information
The genus Trichromothrips comprises about 30 species, almost all of them from the Old World tropics. All members lack ocellar setae I and posteromarginal comb of microtrichia on abdominal tergite VIII. Trichromothrips xanthius is the only known species from Brazil and can be recognized by the presence of a small coarse-grained area on each side of abdominal sternites V–VI.
World distribution
Possibly originated from Southeast Asia; it has been recorded from Brazil, Caribbean and USA.
Breeding on leaves. Apparently associated to Orchidaceae, but also found on grasses and bananas.
Economic importance
Referred as damaging orchids in Caribbean.
References suggested
Masumoto M & Okajima S (2005) Trichromothrips Priesner (Thysanoptera, Thripidae) of Japan and Taiwan, with descriptions of four new species and a review of the Trichromothrips group of genera. Zootaxa 1082: 1–27.
Nakahara S (1993) The genus Dorcadothrips (Thysanoptera: Thripidae) in Hawaii and North America with a description of a new species. Journal of the New York Entomological Society 101(3): 399–409.
Published in: 17/06/2017 Posted by: Mariana Lindner
