Mycosarcoma (Ustilaginaceae), a resurrected generic name for corn smut (Ustilago maydis) and its close relatives with hypertrophied, tubular sori

Ustilago is a polyphyletic genus of smut fungi found mainly on Poaceae . The development of a taxonomy that reflects phylogeny requires subdivision of Ustilago into smaller monophyletic genera. Several separate systematic analyses have determined that Macalpinomyces mackinlayi, M. tubiformis, Tolyposporella pachycarpa, Ustilago bouriquetii and U. maydis , occupy a unique phylogenetic position within the Ustilaginaceae . A previously introduced monotypic generic name typified by U. maydis, Mycosarcoma , is available to accommodate these species, which resolves one component of polyphyly for Ustilago s. lat . in Ustilaginaceae . An emended description of Mycosarcoma is provided to reflect the morphological synapomorphies of this monophyletic group. A specimen of Ustilago maydis that has had its genome sequenced is designated as a neotype for this species. Taxonomic stability will further be provided by a forthcoming proposal to conserve the name Uredo maydis over Lycoperdon zeae , which has priority by date, in order to preserve the well-known epithet maydis .