Spider mites includes about 1,200 species and they generally live on the undersides of leaves of plants, where they may spin protective silk webs, and they can cause damage by puncturing the plant cells to feed. Spider mites are known to feed on several hundred species of plants. They vary in size and in color. They lay small, spherical, initially transparent eggs and many species spin silk webbing to help protect the colony from predators. It’s for this webbing that they get the “spider” part of their name.