Broad and narrow host ranges in resolved species of Cintractia limitata s. lat. (Anthracoideaceae, Ustilaginomycotina) on Cyperus

Abstract

Cintractia (Anthracoideaceae, Ustilaginomycotina) is a widespread genus of smut fungi that parasitizes species of Cyperaceae. Specimens of Cintractia spp. on species of Cyperus s. lat. were examined to resolve their taxonomy, including a species on Cyperus aromaticus, which is an invasive weed in Australia. A phylogenetic species concept was used to show that Cintractia limitata s. lat. contains three different species, Cintractia limitata, C. tangensis, and a new species C. kyllingae. The proposed taxonomy is based on phylogenetic analyses of the ITS rDNA region and on the position of the sori in diverse parts of inflorescences examined in approximately 100 specimens of Cintractia. A morphological synapomorphy in C. tangensis is sori with firmly agglutinated spore masses around the base of the peduncles, rarely in the spikelets. Cintractia limitata forms powdery spore masses between flowers and is known only to occur on Cyperus species with spikelets in capitate heads. Cintractia kyllingae was found on Cy. aromaticus and may have potential as a biological control agent in Australia.