The complete life cycle of Petrakia echinata

The teleomorph of Petrakia echinata (Peglion) Syd. & P. Syd. on leaves of Acer pseudoplatanus is described based on field collections, culture studies and ITS sequencing and was assigned to the genus Mycodidymella C.Z. Wei, Y. Harada & K. Katumoto. In addition, a Mycopappus anamorph and a presumed spermatial Phoma stage were observed and conspecificity with P. echinata was confirmed by culture morphology and ITS sequencing. The phylogenetic relationships between the Mycodidymella teleomorph of P. echinata and related taxa were studied using LSU nDNA sequences. The fungus causes brown spots on the leaves of the host plant, known as Petrakia leaf blotch of sycamore maple.