Abstract
An annotated list of the 34 species of Tetranychidae (including introduced species) known in the Netherlands is presented, their economic importance is discussed. Exotic species get new opportunities to arrive through the plant trade, and possibly also by the prohibition of effective acaricides. This paper was presented at the 1st annual meeting of the section of Experimental and Applied Entomology of the Netherlands Entomological ~Society on 15 December 1989 in Utrecht, Netherlands
