BugWise

What do thrips look like?

Thrip examples. Photo: M Bulbert © Australian Museum.

Thrip. Illustration: A Howells © Australian Museum.

Size:

0.5 mm -15 mm in length but most are shorter than 5 mm.

Body:

Cigar-shaped, column-like or widest at wing attachment (wide shoulders), with abdomen tapering.

Flattened as if pressed from above.

Head square or rectangular-like.

Appears soft or hard.

Antennae:

Bead-like or thread-like.

Never longer than body.

Eyes:

Berry-like.

Very small or large.

Moderately separated.

Mouthparts:

For piercing, scraping and sucking.

Wings:

Two pairs, if present.

Both pairs thin with no more than three veins.

Margins entirely or partially lined with long hairs.

At rest, wings held flat over body and either overlapping or held alongside each other.

Limbs:

Six legs, short and stocky.

Adhesive bladders expand from last tarsal (toe) segment.

Abdomen tip:

Cerci (tails) absent.

Last segment of abdomen may be long and tubular, with a ring of long hairs at the tip.

Where are thrips found?

• On leaves, and fruit.
• On flower heads where they may spend their entire life.
• Axils of grasses, leaves and flower stalks.
• Under bark and among leaf litter, moss and fungi.
• Some live in galls or shelters made by folding leaves. Galls maybe constructed by the thrip or more likely by another insect group.

What do thrips do?

• Most thrips are solitary, though they may form large groups in areas where preferred food sources are minimal.
• Some form colonies in galls or folded leaf-shelters.
• When disturbed they run or fly away.
• Their flight activity is often associated with a change in weather (hence common name 'thunder flies').
• Some flightless species are small enough to be dispersed by wind.
• Most are plant feeders feeding on leaves, pollen, nectar, flowers, fruits and young shoots of trees and shrubs.
• They tend to feed by sucking up juices created after rasping surfaces.
• They may also feed by piercing and sucking out internal juices or eat items whole such as pollen.
• Other thrips feed on fungal spores hyphae.
• Some are predators. Thrip predators prey on eggs, larvae or even the adults of a variety of insects, mites and nematodes.
• Some are pests to crops (mostly introduced species).
• They are active during the day or night. Some night active species are attracted to light.

What looks similar?

• Not readily mistaken due to unique appearance and lifesytle.