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Thysanoptera Californica

How to operate the identification system

All species can vary in color and structure, depending on temperature and food availability during development. Single, isolated individuals are thus difficult to identify if you do not know the extent of variation that occurs within that species. Identifications are therefore best carried out on population samples that include large and small individuals as well as both sexes.

  1. This identification system is computer driven and is designed to function automatically, by selecting the button "Best" screen shot of the "Best" button and alternating this with the button "Prune Redundant Features" screen shot of the "Prune Redundant Features" button. A sophisticated tool, it will NOT function well if it is misused by randomly selecting character states that might seem to be obvious on a particular specimen (but see 7 below).
  2. If you find that a character suggested by the system as “best” is difficult to see, then click for a second or third time on “Best” to find the “next best” option.
  3. Additional features become available as soon as you select the form of the tenth abdominal segment.
  4. View an image of a Feature by clicking the image icon screen shot of the image icon next to it. Or you can turn on the Feature Thumbnails by clicking the "Feature Thumbnails" button screen shot of the "Feature Thumbnails" button.
  5. With a multi-state character, you can select two states if you are not confident about selecting any single state. BUT always use character states that you can see easily and can evaluate confidently.
  6. To view information about each thrips species, click the page icon screen shot of the page icon next to the species name. This identification system should enable the user to identify samples of thrips to species, but isolated individuals can be more difficult due to within-species variation in structure and colour. It is therefore good practice to check any identification against comments on the relevant datasheet.
  7. For an experienced thrips identifier, an alternative method of operating the system is to select character states that, from previous experience, are particularly useful. For example, if you can recognise the existence and position of tergal ctenidia, then selecting the appropriate character state will produce an identification more quickly. But “obvious” states such as colour of wings, legs or antennae are liable to considerable variation within and between populations, and should not be used in the early stages of an identification.