This invention relates to novel methylthiophenecarboxanilides of the formula (I) ##STR00001## in which R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5 and R.sup.6 are as defined in the disclosure, to a plurality of processes for preparing these substances and their use for controlling unwanted micro-organisms, and to novel intermediates and their preparations.