Thrips

Thrips are tiny insects belonging to their own order, Thysanoptera, whose name refers to the distinctive fringe of fine hairs lining the edges of their narrow wings. Despite their minute size, thrips are found on nearly every continent and occupy an enormous range of habitats, most commonly in and around flowers, where they feed and sometimes assist in pollen movement between blossoms.

The word "thrips" is both singular and plural, a quirk of the group's Greek-derived name, so a single individual is correctly called "a thrips," not "a thrip." Their bodies are extremely slender and elongated, built for slipping into the tight folds of flower petals and leaf buds where they feed and shelter.

Thrips have unusual, asymmetrical mouthparts used to punch and rasp at plant cells before sucking up the released fluid, a feeding style unlike the piercing-sucking method used by true bugs. Some species also feed on fungal spores or act as predators of other minute arthropods.

• Extremely small, slender, cigar-shaped body, typically dark brown, black, or pale yellow depending on species.
• Two pairs of very narrow wings fringed with fine hairs, held flat along the back at rest — visible only under magnification.
• Short antennae and unique, asymmetrical rasping-sucking mouthparts adapted for puncturing individual plant cells.
• Movement is quick and erratic; thrips often go unnoticed until disturbed, when they dart rapidly across a surface.
• Lookalikes include tiny aphids or fungus gnats, but thrips are distinguished by their slender cigar shape and characteristic fringed wings under magnification.

Thrips are found worldwide, especially in temperate and tropical regions, inhabiting flowers, foliage, grasses, and crop fields, as well as greenhouses and indoor plants. They are most abundant during warm, dry weather in spring and summer, when populations can build up quickly, and many species shelter deep within flower blooms or unopened buds during the heat of the day.

Thrips feed by rasping the surface of plant cells with specialized mouthparts and drawing up the released cell contents, often leaving fine silvery or stippled scarring on leaves and petals as a result. Movement combines short, weak flight with quick crawling, and thrips are frequently swept into the air by wind currents, which accounts for their sudden mass appearances noticed by people outdoors, sometimes called "thunderflies" for their association with humid, stormy weather. While some thrips species are recognized as plant pests due to their feeding habits, others are predatory, feeding on mites and other minute arthropods, or contribute to pollen transfer as they move between flowers.

Females insert tiny eggs into plant tissue using a small saw-like ovipositor, and the nymphs that hatch resemble miniature, wingless versions of the adult, feeding actively on plant tissue through several nymphal stages. Uniquely among many insects, thrips pass through a resting, non-feeding stage or two, sometimes described as a simplified pupa, before molting into the winged adult form, a pattern intermediate between incomplete and complete metamorphosis. Multiple generations can occur per year in warm climates or greenhouses, with development from egg to adult sometimes taking just two to three weeks under favorable conditions.