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Five yeast isolates belonging to a candidate for novel species were obtained from rotting wood and the gut of a passalid beetle larva in a site of Amazonian rainforest biome in Brazil. Sequence analysis of the Internal Transcribed Spacer (ITS)-5.8S region and the D1/D2 domains of the large subunit rRNA gene showed that the isolates represent a novel species of the genusVanderwaltozyma. The closest relative of the novel species isVanderwaltozyma huisunica. These species differs due to 44 nt substitutions and 21 indels in the sequences of the ITS region, as well as by 15 substitutions and four indels in the sequences of the D1/D2 domains. A phylogenomic analysis of theVanderwaltozymaspecies with genomes sequenced showed that this novel species is an outgroup to the other species of this genus. We propose the nameVanderwaltozyma urihicolasp. nov. (CBS 18107^T, MycoBank MB 856975) to accommodate these isolates. The species is homothallic, producing one to two ascospores per ascus. The habitat ofV. urihicolais rotting wood in the Brazilian Amazonian rainforest biome. 

Abstract The debates over the requirement ofthe International Code of Nomenclature for algae, fungi, and plants(ICNafp) for a viable specimen to represent the name-bearing type material for a species or infraspecific taxon have a long history. Taxonomy of fungi commonly studied as living cultures exemplified by yeasts and moulds, strongly depend on viable reference material. The availability of viable cultures is also particularly useful for several groups of filamentous and dimorphic fungi. While the preservation of metabolically inactive cultures is permitted and recommended by the ICNafp, there is room for improvement. Below, we review the history and current status of cultures as the name-bearing type material under theCode. We also present a roadmap with tasks to be achieved in order to establish a stable nomenclatural system that properly manages taxa typified by viable specimens. Furthermore, we propose setting up rules and defining the nomenclatural status of ex-type cultures under Chapter F, the section of the ICNafp that includes provisions specific to names of fungi. 

Three yeast isolates were obtained from soil and rotting wood samples collected in an Amazonian rainforest biome in Brazil. Comparison of the intergenic spacer 5.8S region and the D1/D2 domains of the large subunit rRNA gene showed that the isolates represent a novel species of the genusSaccharomycopsis. A tree inferred from the D1/D2 sequences placed the novel species near a subclade containingSaccharomycopsis lassenensis,Saccharomycopsis fermentans,Saccharomycopsis javanensis,Saccharomycopsis babjevae,Saccharomycopsis schoeniiandSaccharomycopsis oosterbeekiorum, but with low bootstrap support. In terms of sequence divergence, the novel species had the highest identity in the D1/D2 domains withSaccharomycopsis capsularis, from which it differed by 36 substitutions. In contrast, a phylogenomic analysis based on 1061 single-copy orthologs for a smaller set ofSaccharomycopsisspecies whose whole genome sequences are available indicated that the novel species represented by strain UFMG-CM-Y6991 is phylogenetically closer toSaccharomycopsis fodiensandSaccharomycopsissp. TF2021a (=Saccharomycopsis phalluae). The novel yeast is homothallic and produces asci with one spheroidal ascospore with an equatorial or subequatorial ledge. The nameSaccharomycopsis praedatoriasp. nov. is proposed to accommodate the novel species. The holotype ofSaccharomycopsis praedatoriais CBS 16589^T. The MycoBank number is MB849369.S. praedatoriawas able to kill cells ofSaccharomyces cerevisiaeby means of penetration with infection pegs, a trait common to most species ofSaccharomycopsis.