The Urocystidales are an order of fungi within the class Ustilaginomycetes. The order contains 6 families and about 400 genera. They are a sister order to Ustilaginales.
Urocystidales is also known and classified as the smut fungi. They are serious plant pathogens, Urocystis, is one of the representative genera of the order, it is an example of a smut genus that has a wide host range. The type species Urocystis occulta , was described as a pathogen on rye (Secale cereale). They are found in marine and terrestrial environments. The aquatic members of the Doassansiopsis genera are found in the tropics or subtropics.E. B. Gareth Jones, Kevin D Hyde and Ka-Lai Pang (editors)
Morphology They are distinguished from other fungi by the existence of haustoria (root-like structure) and pores in the septa of soral hyphae.David J. McLaughlin and Joseph W. Spatafora (editors)
Families It was formed in 1997, and consisted (then) of 4 families, (Doassansiopsidaceae, Glomosporiaceae, Melanotaeniaceae and Urocystidaceae with 1 genus.Geoffrey Clough Ainsworth
Later, Melanotaeniaceae was moved to the Ustilaginales order by Begerow et al. in 2006,Begerow D, Stoll M, Bauer R.2006. A phylogenetic hypothesis of Ustilaginomycotina based on multiple gene analyses and morphological data. Mycologia 98: 906–916 and others were added such as Fereydouniaceae and Floromycetaceae in 2014 , and Mycosyringaceae in 2008.Vánky K, Lutz M, Bauer R.2008. About the genus Thecaphora (Glomosporiaceae) and its new synonyms. Mycological Progress 7: 31–39
As accepted by GBIF and others;Outline of Basidiomycota, Mao-Qiang He, Rui-Lin Zhao, in Encyclopedia of Mycology, 2021 Doassansiopsidaceae (19) - only includes Doassansiopsis Fereydouniaceae (3) - includes Fereydounia Floromycetaceae (21) - includes Antherospora and Floromyces Glomosporiaceae (117) - includes Thecaphora (incl. Glomosporium Sorosporium) Mycosyringaceae (5) - includes Mycosyrinx Urocystidaceae (228) - includes Flamingomyces, Melanoxa, Melanustilospora, Mundkurella, Tuburcinia, Urocystis, Ustacystis and Vankya
Figures in brackets are approx. how many species per family.
Note the DNA of family Doassansiopsidaceae has been studied.Begerow, D., Bauer, R. & Oberwinkler, F. 1998. Phylogenetic studies on nuclear large subunit ribosomal DNA sequences of smut fungi and related taxa. – Canadian Journal of Botany 75 : 2045-2056.
Ecology The leaves of the water-lily (Nymphaea nouchali) can be affected by the water-born fungi, Doassansiopsis nymphaea.Dr.V.R. Patil
The leaves of Caldesia parnassifolia (Alisma reniforme) can be affected by the water-born fungi, Doassansiopsis hydrophila (syn Doassansiopsis martianoffiana).B D Borse, K N Borse, S Y Patil, C M Pawara, L C Nemade and V R Patil
References
Other sources C.J. Alexopolous, Charles W. Mims, M. Blackwell et al., Introductory Mycology, 4th ed. (John Wiley and Sons, Hoboken NJ, 2004)