Description

Chilli thrips is an invasive agricultural pest native to southern Asia. It has spread to most regions of the world. Adult chilli thrips measure 1 mm to 2 mm in body length. The body is narrow, pale yellow to orange-yellow. The two pairs of dark wings bear fringes of long hairs (alar setae) along leading and trailing edges, a characteristic shared by other winged members of the order Thysanoptera. Immature chilli thrips are similar in appearance to adults but are smaller, with less developed, pale wings. Wings are absent on early stage nymphs. The antennae are eight-segmented, and the mouthparts are not visible from above. Microscopic examination reveals the unusual structure of the mouthparts shared by all Thysanoptera. The mandibles are asymmetrically developed. The left mandible is a jagged, rasping organ, and the right mandible is greatly reduced or absent. Note that the common name of insects in the order Thysanoptera, thrips, is both singular and plural (i.e., the singular of thrips is “thrips” not “thrip”).

Species identification of thrips is challenging due to their small sizes and similar appearances, especially those in the agriculturally important family Thripidae. Identification requires specialized mounting of specimens on microscope slides for examination and diagnosis. The shape of the last abdominal segment, arrangements of hairs (setae) on the body segments, and color and arrangement of alar setae are important features used in identification. Positive identifications should be performed by a qualified insect diagnostician or insect taxonomist, especially in agricultural situations where pesticide treatments are under consideration. Among approximately 8,000 described species in the order Thysanoptera, about 100 are members of the genus Scirtothrips, which includes chilli thrips. Only a small percentage of thrips are known to be pests, and some are even predators. This makes correct identification critical to avoid unnecessary pest control treatments.

Life Cycle

Thysanoptera undergo an unusual series of developmental stages. These stages include egg, two larval stages, prepupa, pupa and adult. This life cycle is considered to evolutionarily intermediate between insects having partial metamorphosis (hemimetabolous) (e.g., true bugs) and those having complete metamorphosis (holometabolous) (e.g., beetles). The life cycle of chilli thrips starts when gravid females deposit eggs inside plant tissues using a specially adapted egg laying organ (ovipositor) at the end of the abdomen. First stage larvae hatch within five to eight days, begin feeding and quickly develop into second stage larvae. She may lay up to 200 eggs during a typical adult lifespan, which may last up to four weeks under favorable conditions. The larval stages are morphologically similar to adults, in contrast to insects having true complete metamorphosis. The two larval stages require eight to 10 days to fully mature. Prepupal and pupal stages do not feed and remain stationary. These two stages may be completed in three to four days. Chilli thrips in more temperate areas may undergo eight generations annually, while those in more tropical regions can complete as many as 18 generations. Population size is accelerated by the ability of the females to produce viable eggs without mating (parthenogenesis) during some parts of the season.

Larvae and adults feed by piercing the host plant cuticle using the rasping-sucking mouthparts and injecting salivary enzymes into the wound. This creates a slurry of partially digested plant tissues that are then ingested. Feeding activity produces characteristic scars that serve as early warning of infestations.

Ecological Significance and Pest Status

Chilli thrips are distributed worldwide, but infestations are most serious in tropical and subtropical regions. Damaging infestations have been recorded in eastern Asia, Africa, Oceania and America. The species has been recorded on more than 100 plant hosts, including economically important vegetables and ornamentals. Examples include banana, cocoa, corn, cotton, grapes, kiwi, melon, peanut, pepper, strawberry and roses. The first records in continental U.S. are from Florida during 2005, followed by rapid spread throughout the Gulf Coast. In Louisiana, chilli thrips damage in 2024 affected ornamentals and garden vegetables and was especially severe on peppers.

Chilli thrips damage affects leaves, fruits and shoots. Extensive feeding can lead to leaf surface discoloration, stippling on leaves and fruits, as well as curling and distortion of leaves and terminals. Additionally, they can cause grey to black markings on fruits and stunt plant growth. The species is capable of vectoring a variety of plant viruses, although, to date, virus transmission has not been documented in the U.S.

Control

Best management practices of thrips include scouting, sanitation, exclusion, biological control and chemical control. Current recommendations for nursery stock suggest delaying insecticide applications when thrips are first detected and managing populations throughout initial plant growth stages prior to shipment of final products. Regular scouting is crucial to detect thrips early and prevent economic damage. Sanitation practices, such as removing weeds and old plant debris, are recommended to eliminate thrips’ habitats. Exclusion techniques, such as screening greenhouse openings, can prevent adult thrips from entering. Biological control using predators, nematodes and entomopathogenic fungi should be initiated early in the infestation for optimal effectiveness. Conservation of natural enemies of thrips such as predatory mites (Amblyseius spp.), minute pirate bugs (Orius spp.) and lacewings (Chrysopidae) can be effective in suppressing populations. Chemical control should be used judiciously and only after correct identifications of potential pest species have been performed. Rotating insecticide modes of action to avoid resistance development is critical. Contact specialists in the LSU AgCenter’s Extension service and the latest Insect Pest Management Guides for the most up-to-date recommendations.

References

Chen, Yan, S. Arthurs, and D. Ring. 2016. Chilli Thrips Control, Identification and Management. LSU AgCenter. (accessed 1 December 2025).

Jha, V.K., D.R. Seal, and G. Kakkar. 2010. Chilli thrips Scirtothrips dorsalis Hood (Insecta: Thysanoptera: Thripidae). University of Florida IFAS Extension. EENY 463. (accessed 30 January 2026).

LSU AgCenter. 2025. Insect Pest Management Guides. (accessed 2 December 2025).

Revynthi, A., V. Kumar, G. Kakkar, C. Palmer, C.L. McKenzie, and L.S. Osborne. 2016. Thrips management program for horticultural crops. University of Florida IFAS Extension. EENY 987. (accessed 30 January 2026).

Soloneski, S., and M. Larramendy (eds.). 2013. Weed and Pest Control: Conventional and New Challenges. BoD–Books on Demand. 216 pp.

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