Violaceomyces palustris gen. et sp. nov. and a new monotypic lineage, Violaceomycetales ord. nov. in Ustilaginomycetes

Abstract

Numerous strains of a novel yeast were isolated in Louisiana, USA, from the leaves of several palustrine plants, most frequently from the invasive aquatic ferns Salvinia minima and S. molesta. This fungus produced fast-growing colonies that were grayish violet to dark blue in culture and rapidly reproduced via production of copious ballistoconidia that germinated to form pseudohyphae. Colonies produced many two-celled yeasts that were distinctly hourglass-or peanut-shaped, and occurred singly or in chains. Phylogenetic analyses of translation elongation factor 1-α, β-tubulin and the nuc rDNA regions encompassing 28S D1-D2 domains, 18S and the internal transcribed spacers 1 and 2, including 5.8S, indicate this fungus is a member of Ustilaginomycetes but holds an isolated position, distinct from the two currently recognized orders, Ustilaginales and Urocystales. Here we describe Violaceomycetales ord. nov., Violaceomycetaceae fam. nov. and Violaceomyces palustris gen. et sp. nov. for this unusual fungus.

Pattersoniomyces tillandsiae gen. et comb. nov.: linking sexual and asexual morphs of the only known smut fungus associated with Bromeliaceae

“…Mitch. (Albu et al 2015). However, several other ascomycetous or basidiomycetous yeasts were found to be consistently associated with bromeliads (Landell et al 2010(Landell et al , 2015Safar et al 2013;Gomes et al 2015Gomes et al , 2016 but it is currently unknown which factors are responsible for such a habitat preferences of these yeast species.…”

“…Interestingly, only Pattersoniomyces shares its occurrence between North and South America, being a truly neotropical genus. Clintamra Cordas & Durán, Exoteliospora R. Bauer, (Lutz et al 2012;Suh et al 2012;Albu et al 2015). The low endemism of smut genera in South America is noteworthy as it contrasts with the very high host plant diversity, but one reason may be that a vast area of South America is covered with rainforest that is not a suitable ecosystem for the occurrence of smut fungi (Piepenbring et al 2011).…”

Integrative analysis of the West African Ceraceosorus africanus sp. nov. provides insights into the diversity, biogeography, and evolution of the enigmatic Ceraceosorales (Fungi: Ustilaginomycotina)

“…Moreover, similar to other lineages of Ustilaginomycotina, saprobic yeast species may contribute to unknown Ceraceosorus diversity. In fact, one yeast species assigned to this genus was announced but not yet described (Kijpornyongpan and Aime 2014;Albu et al 2015).…”

“…Several species were also isolated from healthy plant tissues and may act as endophytes (Paz et al 2007;Amin et al 2010;Takahashi et al 2011;Padhi and Tayung 2013;Rush and Aime 2013). The most notable of them is the recently described Violaceomyces palustris Albu, Toome & Aime that represents a distinct lineage, the order Violaceomycetales (Albu et al 2015). Sporulation in the Ustilaginomycotina is notably diverse, including budding cells, simple hyphae with conidiogenous cells producing conidia, teliospores embedded between plant cells or replacing generative or vegetative plant organs, and loose fascicles or hymenial layers of basidia emerging from stomata or the epidermis.…”

Graphiola fimbriata: the first species of Graphiolaceae (Exobasidiales, Basidiomycota) described only based on its yeast stage

“…The subphylum Ustilaginomycotina comprises a highly diverse assemblage of fungi, including teliosporic plant pathogens, non-teliosporic plant pathogens, anamorphic plant pathogens, as well as endophytic, lipophilic, saprobic, and zoophilic yeasts (Begerow et al 2014). The orders Malasseziales, Monilielalles, and Violaceomycetales include exclusively yeast species of the genera Malassezia, Moniliella, and Violaceomyces, respectively (Wang et al 2014, Albu et al 2015, while the remaining yeasts and yeast-like fungi are scattered amongst the remaining orders of Ustilaginomycotina, with the exception of the members of Doassansiales, Tilletiales and Uleiellales for which no yeasts have been discovered so far.…”