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#17: Thrips


Litinsects #17: Thrips

Today I’m talking about a lesser known group of insects called thrips, which most people probably haven’t seen before because they are quite tiny. I worked with thrips for my master’s thesis so I was able to learn a lot about them and get these great photos. Here go some fun facts...

  • Thrips are small insects (around 1mm) with very narrow and fringed wings that make up the order THYSANOPTERA (Greek thysanos =fringe, pteron = wing). FYI, thrips is both the singular AND the plural form
  • Their mouthparts are ASYMMETRICAL, a feature that is unique to the group. The right side is reduced (vestigial) or absent and only the left side is used to scrape open plant cells and extract contents
  • These insects feed on a wide variety of plants and are often considered PESTS of commercial crops. They are also vectors for plant diseases
  • Thrips go through incomplete metamorphosis (which I will explain in a post coming up). They lay their eggs into plant tissue, have two feeding nymphal stages, and two non-feeding nymphal stages before reaching adulthood
  • Finally, thrips use an interesting sex-determination system called HAPLODIPLOIDY. Males arise from unfertilized eggs and females from fertilized eggs so males actually only have half as many chromosomes as females!

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