Print Fact SheetIridothrips iridis

Distinguishing features

Female usually micropterous, but sometimes fully winged. Body brown to dark brown, tarsi and apices of tibiae yellow, also antennal segments III–V; fore wing pale. Antennae 8-segmented; segment III with sense cone simple, IV with sense cone Y-shaped, VIII scarcely longer than VII. Head slightly longer than wide, projecting in front of eyes; three pairs of ocellar setae present, pair III as long as anterolateral margin of ocellar triangle, arising just anterior to lateral margins of triangle; postocular setae pair I present, pair II displaced to posterior, pair IV as long as diameter of one hind ocellus. Pronotum with 5 pairs of major setae; anteromarginal setae shorter than anteroangulars, one pair of minor setae present medially between posteromarginal submedian setae. Mesothoracic furca lacking a spinula. Metanotum reticulate, with 2 pairs of setae at anterior margin, campaniform sensilla absent. Fore wing with 2 complete rows of veinal setae; microptera with wing lobe about 150 microns long. Abdominal tergites V–VIII with paired ctenidia, on VIII anterolateral to spiracle; tergite VIII posterior margin with no comb but with a few dentate lobes laterally. Sternites III–VII without discal setae, VII with posteromarginal setal pair S1 arising at margin.
Male micropterous, similar to female but smaller; fore wing lobe scarcely 100 microns long; tergite VIII with no posteromarginal comb, IX with median setae slender; sternites III–VII each with narrow transverse pore plate.

Related species

The European genus Iridothrips comprises just two species, with mariae and iridis very similar in structure  (zur Strassen, 2003). The genus is closely related to Frankliniella, but the mesothoracic furca lacks a spinula and the sense cones on antennal segments III and IV are simple rather than bifurcate.

Biological data

Feeding and breeding primarily on the leaf sheaths (Jenser, 2013) of Iris pseudacorus, but possibly also on related Iridaceae.

Distribution data

This species has been recorded only infrequently in Britain, at various localities from Surrey to as far north as Stirling in Scotland (Mound et al., 1976: as Frankliniella iridis), but it is widespread across Scandinavia and Central Europe east to Bulgaria (e.g., Gertsson, 2015; Karadjova & Krumov, 2015). It has been introduced into the USA (Stannard, 1968).

Family name


Species name

Iridothrips iridis (Watson)

Original name and synonyms

Bregmatothrips iridis Watson, 1924: 253


Gertsson C-A (2015) An annotated checklist of Thysanoptera (thrips) from the Nordic countries. Entomologisk Tidskrift 136 (4): 185–198.

Jenser G (2013) Iridothrips iridis (Watson, 1924) (Thysanoptera: Thripidae): an unusual species of thrips that lives in a subaquatic habitat. Acta Zoologica Academiae Scientiarum Hungaricae 59: 61–66.

Karadjova O & Krumov V (2015) Thysanoptera of Bulgaria. ZooKeys 504: 93–131.

Mound LA, Morison GD, Pitkin BR & Palmer JM (1976) Thysanoptera. Handbooks for the Identification of British Insects 1 (11): 1–79.

Stannard LJ (1968) The thrips, or Thysanoptera, of Illinois. Bulletin of the Illinois Natural History Survey 29: 213–552.

zur Strassen R (2003) Die terebranten Thysanopteren Europas und des Mittelmeer-Gebietes. Die Tierwelt Deutschlands 74: 1–271.