title: Novel soil-inhabiting clades fill gaps in the fungal tree of life.
abstract: Fungi are a diverse eukaryotic group of degraders, pathogens, and symbionts, with many lineages known only from DNA sequences in soil, sediments, air, and water.
  
  
  
  We provide rough phylogenetic placement and principal niche analysis for >40 previously unrecognized fungal groups at the order and class level from global soil samples based on combined 18S (nSSU) and 28S (nLSU) rRNA gene sequences. Especially, Rozellomycota (Cryptomycota), Zygomycota s.lat, Ascomycota, and Basidiomycota are rich in novel fungal lineages, most of which exhibit distinct preferences for climate and soil pH.
  
  
  
  This study uncovers the great phylogenetic richness of previously unrecognized order- to phylum-level fungal lineages. Most of these rare groups are distributed in different ecosystems of the world but exhibit distinct ecological preferences for climate or soil pH. Across the fungal kingdom, tropical and non-tropical habitats are equally likely to harbor novel groups. We advocate that a combination of traditional and high-throughput sequencing methods enable efficient recovery and phylogenetic placement of such unknown taxonomic groups.
authors.affiliation: Natural History Museum, University of Tartu, 14a Ravila, 50411, Tartu, Estonia. leho.tedersoo@ut.ee.
authors.forename: Leho
authors.initials: L
authors.lastname: Tedersoo
authors.affiliation: Institute of Ecology and Earth Sciences, University of Tartu, 14a Ravila, 50411, Tartu, Estonia.|Systematic Biology, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, 75236, Uppsala, Sweden.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Bahram
authors.affiliation: Institute of Ecology and Earth Sciences, University of Tartu, 14a Ravila, 50411, Tartu, Estonia.
authors.forename: Rasmus
authors.initials: R
authors.lastname: Puusepp
authors.affiliation: Department of Biological and Environmental Sciences, University of Gothenburg, Box 463, 405 30, Göteborg, Sweden.
authors.forename: R Henrik
authors.initials: RH
authors.lastname: Nilsson
authors.affiliation: Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, 48109, USA.
authors.forename: Timothy Y
authors.initials: TY
authors.lastname: James
mesh_terms: D001483:Base Sequence; D004271:DNA, Fungal / Q000235:genetics; D021901:DNA, Intergenic / Q000235:genetics; D017753:Ecosystem; D005658:Fungi / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D059014:High-Throughput Nucleotide Sequencing; D012337:RNA, Ribosomal, 18S / Q000235:genetics; D012339:RNA, Ribosomal, 28S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012988:Soil Microbiology
chemical_list: D004271:DNA, Fungal; D021901:DNA, Intergenic; D012337:RNA, Ribosomal, 18S; D012339:RNA, Ribosomal, 28S
keywords: Biogeography; Kingdom Fungi; Niche modelling; Phylogenetic lineages; Random forest