One Fungus = One Name: DNA and fungal nomenclature twenty years after PCR

Abstract

Some fungi with pleomorphic life-cycles still bear two names despite more than 20 years of molecular phylogenetics that have shown how to merge the two systems of classification, the asexual "Deuteromycota" and the sexual "Eumycota". Mycologists have begun to flout nomenclatorial regulations and use just one name for one fungus. The International Code of Botanical Nomenclature (ICBN) must change to accommodate current practice or become irrelevant. The fundamental difference in the size of fungi and plants had a role in the origin of dual nomenclature and continues to hinder the development of an ICBN that fully accommodates microscopic fungi. A nomenclatorial crisis also looms due to environmental sequencing, which suggests that most fungi will have to be named without a physical specimen. Mycology may need to break from the ICBN and create a MycoCode to account for fungi known only from environmental nucleic acid sequence (i.e. ENAS fungi).

Keywords: Amsterdam Declaration; ENAS; MycoCode; nomenclature; pleomorphic fungi.

Fig. 1.

Phylogenetic relationships of the sister species Crivellia papaveracea and Brachycladium papaveris, the former named as teleomorphic and the latter as an anamorphic fungus. The Crivellia state of B. papaveris remains unnamed due to a lack of suitable material to serve as a nomenclatural type (Inderbitzen et al. 2006).

Fig. 2.

Louis Renè Tulasne (l) and Charles Tulasne (r). Photo: courtesy of the National Museum of Natural History, Paris.

Fig. 3.

Phylogenetic analysis of PCR amplified rDNA showing the evolution of hypogeous Basidiomycota in the genus Rhizopogon, from mushroom ancestors in the genus Suillus (Bruns et al. 1989). Adapted from Bruns et al. (1989).

Fig. 4.

Authors of the publication of PCR primers for the amplification and direct sequencing of fungal ribosomal RNA genes for phylogenetics. Left to right: Tom Bruns, Tom White, Steve Lee, and John Taylor. Photo: taken in 2010, 20 years after the publication of White et al. (1990).

Fig. 5.

Phylogenetic analysis of PCR amplified rDNA showing the anamorphic Sporothrix schenckii nestled within the teleomorphic genus Ophiostoma (Berbee & Taylor 1992).

Fig. 6.

Graph of the Operational Taxonomic Units (OTUs) added to GenBank from 1991 to 2009 showing the increasing proportion of OTUs based only on environmental nucleic acid sequence (ENAS). Adapted from Hibbett et al. (2011).