|MadSci Network: General Biology|
Dust mites are tiny arachnids of the Acaris family, that are at most 300 microns in length ( approx. 1/4 of a millimeter) with translucent bodies, so you would need at least 10X magnification to see them. Most standard microscopes have 10X eyepieces, so a 5X or greater objective (the removable lens closest to the stage) should work well. If you have access to a dissecting scope, you should be able to visualize at the upper end of the magnification range - most dissecting scopes have 2X eyepieces with a 1X to 10X adjustable objective.
Regarding prepared slides of dust mites for comparison, I searched all over the web, and couldn't find specific slides, but I know there are a few scientific supply companies that make sets of slides for educational purposes, and I would expect one of these sets contains prepared dust mites. However, fixed, dehydrated dust mites look very different from live dust mites, but dust mites are so prevalent, that you would probably recognize them as soon as you saw them. Alternatively, you can use a test kit called Acarex, from Fisons, which can tell you if dust mites are present without having to actually see them.
Dust mites do not eat paper, neither do any of their acarid relatives - there are no paper mites. There are several paper-eating insects, including book lice and silverfish, but as insects they are in a different Class than arachnids like dust mites. Dust mites are pests, though, in so far as they are the leading causes of allergies in the world today. As such, several products have been formulated to eradicate dust mites from houses of allergy sufferers.
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