Ligniera junci, a plasmodiophorid parasite of Juncus spp. was found at three locations in Tyrol. The morphologically similar plasmodiophorid of Poaceae Polymyxa graminis was found to co-occur at two of these locations. This is the first record of these species in Austria. Colour photographs of resting spores of Ligniera junci in roots of Juncus triglumis and Polymyxa graminis in roots of Poaceae are given. A description of Ligniera junci supported by light micrographs of different stages of the life-cycle (sporosori, zoosporangia, zoospores) is presented.