Iris Thrips – Iridothrips iridis

Iris Thrips (Iridothrips iridis)

Common Name: Iris Thrips

Latin Name: Iridothrips iridis


  • Thrips are very little insects with long, thin bodies. Their length ranges from less than 1/16 inch to around 3/16 inch. If you use magnification, you will be able to distinguish the adults, which can be any color from yellow to black, and have four wings that are extremely long, slender, and fringed.
  • The immature nymphs range in hue from yellow to white and are much smaller than their adult counterparts.
  • Most thrips are herbivorous insects that eat on plants and can damage flowers, leaves, fruit, twigs, or buds.

Host plant:

Iridaceae and monophagous are the most common host plants.


This species has only been observed in Britain occasionally, from Surrey to as far north as Stirling in Scotland. However, it is common in Scandinavia and Central Europe, stretching east to Bulgaria. It has been introduced in the United States.

Damages caused by Iris Thrips:

Iris thrips cause reduced development and rusty or sooty patches on the leaves. Infested plants’ tops gradually turn brown and die. Serious infestations can destroy virtually all of the roots, leaving the plants susceptible to fungal attacks.

Life history and habits:

Trees and bushes have eggs placed into their leaves, fruit, stems, or bark. Pale, wingless nymphs emerge one to two weeks later and eat aggressively until they pupate. Some species cocoon the pupa on the ground or the host plant. Adult thrips emerge from their cocoon or pupal stage. Generations can happen every two to three weeks. However, most people are around from late spring to midsummer. Thrips spend the winter as eggs.