Pygmaeomycetaceae, a new root-associated family in Mucoromycotina from the pygmy pine plains

ABSTRACT

A new genus, Pygmaeomyces, and two new species are described based on phylogenetic analyses and phenotypic and ecological characters. The species delimitation was based on concordance of gene genealogies. The Pygmaeomyces cultures were isolated from the roots of mountain laurel (Kalmia latifolia) and pitch pine (Pinus rigida) from the acidic and oligotrophic New Jersey pygmy pine plains; however, they likely have a broader distribution because their internal transcribed spacer (ITS) sequences have high similarity to a number of environmental sequences from multiple independent studies. Based on the phylogeny and phenotypic characters, a new family, Pygmaeomycetaceae, is proposed to accommodate this new lineage in Mucoromycotina. Pygmaeomycetaceae corresponds to Clade GS23, which was identified based on a sequence-only soil fungal survey and was believed to be a distinct new class. Compared with the culture-based methods, we observed that sequence-only analyses tend to overestimate the taxonomic level. Results from this work will facilitate ecological and evolutionary studies on root-associated fungi.

KEYWORDS:

• Mucoromycota
• phylogeny
• systematics
• taxonomy
• 4 new taxa

ACKNOWLEDGMENTS

The first author would like to thank her father, T. A. Walsh, who enjoyed hearing tales of her collecting trips and about the progress of her research, experiments, and papers. And as an English Literature teacher fond of puns, he found a way to incorporate fungi into the everyday; he became a man of morels and was overall a truly fun guy.

Supplemental data for this article can be accessed on the

Supplemental data for this article can be accessed on the publisher’s website.

Additional information

Funding

The research was supported by the National Science Foundation (DEB 1452971) and the Rutgers University Alberts Research Awards in Biodiversity.