Thrips, (Thysanoptera: Thripidae), adult. Photo by Drees.
Common Name: Thrips
Scientific Name: Varies
Order: Thysanoptera
Description: Adults are small, yellowish and have hair-fringed wings that are usually held across the back. Immature thrips are similar to adults but are wingless.
Other common thrips species found in Texas include: onion thrips, Thrips tabaci Lindeman; citrus thrips, Scirtothrips citri (Moulton); greenhouse thrips, Heliothrips haemorrhoidalis (Bouche); gladiolus thrips, Thrips simplex (Morison); and tobacco thrips, Frankliniella fusca (Hinds). Some thrips species are predaceous on other arthropods.
Life Cycle: Adult female thrips insert eggs into plant tissues. Just before hatching, the egg “squeezes” out of the tissue and hatches. Development progresses through two larval stages (instars), a pre-pupal non-feeding stage that crawls down into the soil, and a pupal resting stage from which adults emerge. Development from egg to adult takes 8 to 20 days depending on temperature..
Habitat and Food Source(s): Thrips are characterized by having a single mandible (jaw) used for rasping. This sword-like mandible is extruded when the mouth cone is compressed on plant tissue. The extruded mandible slashes open epidermal cells. The contents of the opened cells are then sucked in through the cone. Western flower thrips feed on a wide variety of plants including chrysanthemums, gloxinia, impatiens, tomato, vegetables and grasses. Some plants species, varieties and cultivars are more attractive to the thrips than others. Thrips can be detected by beating flowers onto a piece of paper and looking for tiny walking dashes (“-“). They can be collected with a small paint brush and preserved in alcohol.
Pest Status: Feeding injures developing and mature tissues of many plant parts including buds, leaves, flowers, and fruit; capable of “biting” people by poking their single mandible into exposed skin (This is often the case after people sit down in Texas’ beautiful spring wild flower blooms to have their pictures taken. These wild flowers are filled with thrips!); capable of spreading plant diseases such as tomato spotted wilt.
For additional information, contact your local Texas A&M AgriLife Extension Service agent or search for other state Extension offices.
Literature: Drees and Cole 1990.