A shipment of Fults alkaligrass seed (Puccinellia distans) grown in Washington state containing bunted florets was intercepted by quarantine officials at China's Tianjin Entry-Exit Quarantine and Inspection Bureau. The bunted florets were filled with irregularly shaped, reticulately ornamented teliospores that germinated in a manner characteristic of systemically infecting Tilletia spp. on grass hosts in subfamily Pooideae. Based on morphological characters and a multigene phylogenetic analysis of the ITS region rDNA, eukaryotic translation elongation factor 1 alpha and a region of the second largest subunit of RNA polymerase II including a putative intein, the Puccinellia bunt is genetically distinct from known species of Tilletia and is proposed as a new species, T. puccinelliae.