Thysanoptera

Haliday, 1836

Thrips

Family Guides

6

() are minute insects, most measuring 1 mm or less, characterized by slender bodies and fringed wings. The order contains approximately 6,000 described across multiple including Thripidae, Aeolothripidae, Phlaeothripidae, and Merothripidae. Thrips exhibit a distinctive intermediate between incomplete and complete , with two feeding nymphal instars followed by non-feeding propupal and pupal stages. Many species are significant agricultural pests, feeding on plant tissues and transmitting plant viruses in the Tospovirus, while others function as of pest insects and mites or feed on fungal spores and pollen.

Leptothrips by (c) Summit Metro Parks, some rights reserved (CC BY), uploaded by Summit Metro Parks. Used under a CC-BY license.Thripidae by no rights reserved, uploaded by Jesse Rorabaugh. Used under a CC0 license.Hercinothrips femoralis by no rights reserved, uploaded by Jesse Rorabaugh. Used under a CC0 license.

Pronunciation

How to pronounce Thysanoptera: /θaɪsəˈnɒptərə/

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

are distinguished from other insects by their minute size (typically ≤1 mm), slender elongated bodies, and distinctive fringed wings with long setae along the margins. The wings are narrow with reduced venation and function via a 'clap and fling' mechanism rather than conventional . A unique diagnostic feature is the asymmetrical mouthparts: only a single functional remains (the other aborts during embryogenesis), used to rasp plant tissue before siphoning fluids. are short with 6-9 segments. Wingless larvae and winged occur in most .

Images

Habitat

Found in diverse environments including agricultural fields, greenhouses, parks, home gardens, and natural vegetation. Many occupy protected microhabitats such as lower leaf surfaces, flower buds, and leaf axils. Some species are associated with specific plants including ornamentals, vegetables, and field crops. Fossil evidence indicates have inhabited forested environments with resin-producing trees since at least the Miocene.

Distribution

distribution with documented across all continents. Specific survey data records presence in Turkey (Çukurova region), Argentina (Humid Pampas), United States (California, Arizona), and Ethiopia (fossil specimens from north-western Plateau). GBIF distribution records include Denmark, Norway, Sweden, Vermont (USA), and broader US records.

Diet

Most feed on plants by rasping epidermal tissue and siphoning contents, causing stippling, silvering, or scarring of leaves, flowers, and fruits. Some species are pollen feeders. Others are predatory, feeding on other insects and mites; documented predatory species include Franklinothrips orizabensis which preys on Scirtothrips perseae and Heliothrips haemorrhoidalis. Some species feed on fungal spores.

Life Cycle

Development includes , two feeding nymphal instars, and two non-feeding quiescent stages (propupa and pupa) before . This represents an intermediate condition between the of other exopterygotes and complete of endopterygotes. time can be rapid; bean thrips (Caliothrips phaseoli) completes egg-to-egg cycle in approximately 2 weeks under favorable conditions. is often parthenogenetic; in laboratory studies, female onion thrips (Thrips tabaci) produced female offspring without .

Behavior

is weak and primarily wind-assisted; readily disperse long distances by floating on air currents. Feeding involves using the single to rasp an opening in tissue, then siphoning exuded fluids. Some exhibit fastidious defecation behavior, depositing fecal material on leaf hairs away from feeding sites. Predatory species actively hunt prey thrips. Virus transmission occurs when larvae acquire virus from infected plants and retain it through development, spreading it throughout their lives.

Ecological Role

Major agricultural pests causing direct feeding damage and transmitting tospoviruses ( Tospovirus) including tomato spotted wilt virus, iris yellow spot virus, and impatiens necrotic spot virus. Frankliniella occidentalis alone comprises over 80% of specimens in some agricultural surveys. Some serve as agents, preying on pest thrips and other small arthropods. Pollen-feeding species may contribute to pollination, though they can also reduce flower longevity.

Human Relevance

Cause billions of dollars in crop losses worldwide through direct feeding damage and virus transmission. Major pests of lettuce, onion, tomato, strawberry, grape, soybean, and ornamental plants. Frankliniella occidentalis, Thrips tabaci, and Scirtothrips perseae are among the most economically damaging . Biosecurity concerns exist due to wind-assisted and establishment of species. Management challenges include resistance, short times, and protected feeding locations. Research focuses on RNAi biotechnology, cultural practices, and epidemiological modeling for .

Misconceptions

The '' is grammatically singular despite its plural appearance; 'a thrips' is correct usage, analogous to 'a ' or 'a deer.' This causes persistent confusion even among entomologists.

Sources and further reading