Emendation of the basidiomycetous yeast genus Kondoa and the description of Kondoa aeria sp nov

The genus Kondoa Y. Yamada, Nakagawa & Banno was erected to accommodate a s ingle taxon, K. malvinella (Fell & Hunter) Y. Yamada, Nakagawa & Banno, whi ch was transferred from the teliospore-forming genus Rhodosporidium Banno b ased on pronounced differences in the 5S and 26S ribosomal RNA (rRNA) nucle otide sequences to R. toruloides Banno. In contrast with the original descr iption, reinvestigation of K. malvinella revealed the formation of transver sely septate (auricularioid) basidia that did not arise on teliospores, but formed directly on the dikaryotic mycelium. The four-celled basidia develo ped sterigmata on which forcibly discharged asymmetric basidiospores (balli stospores) were produced. Additionally, a new taxon emerged from the study of recent isolates, for which the name K. aeria sp. nov. is proposed. This new species produced two-celled auricularioid basidia on hyphae with incomp lete clamp connections. Ballistospores arose on the basidia at the tip of s terigmata and, after ejection, germinated by budding. These observations le d us to present an emended diagnosis for the genus Kondoa. Analysis of the sequence data from the D1/D2 region of the 26S rRNA gene showed a very clos e resemblance between K aeria and K. malvinella in a cluster that also cont ained several Bensingtonia species. Taxa in this cluster share specific phy siological traits and produce characteristic pinkish-cream to mauve colonie s; in contrast, formation of ballistoconidia is only observed in the Bensin gtonia species. Sequence data supported placement of K. malvinella and K. a eria in the 'Agaricostilbum clade' of the Urediniomycetes.