From one to six: unrecognized species diversity in the genus Acantholichen (lichenized Basidiomycota: Hygrophoraceae)

Mycologia. 2016 Jan-Feb;108(1):38-55. doi: 10.3852/15-060. Epub 2015 Nov 17.


We present a taxonomic revision of the lichenized basidiomycete genus Acantholichen, species of which produce a characteristic blue-gray, microsquamulose thallus with spiny apical hyphal cells known as acanthohyphidia. Since its discovery, the genus was thought to be monospecific, only including the generic type, A. pannarioides. However, a detailed morphological and anatomical study of recently collected specimens from the Galápagos, Costa Rica, Brazil and Colombia, combined with a molecular phylogenetic analysis of the internal transcribed spacer (ITS1-5.8S-ITS2) region and 28S of the nuc rDNA and RPB2 sequences, revealed a much more diverse and widespread species assemblage. Based on the results of these analyses, we describe five new species in the genus: A. albomarginatus, A. campestris, A. galapagoensis, A. sorediatus and A. variabilis. We also provide an identification key to all species, anatomical and morphological descriptions, photographs and a table comparing main characters of each species.

Keywords: Basidiolichens; lichenized fungi; montane forest; phylogeny; taxonomy; tropical diversity.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Base Sequence
  • Basidiomycota / classification*
  • Basidiomycota / cytology
  • Basidiomycota / genetics
  • Brazil
  • Colombia
  • Costa Rica
  • DNA, Fungal / chemistry
  • DNA, Fungal / genetics
  • DNA, Ribosomal Spacer / chemistry
  • DNA, Ribosomal Spacer / genetics
  • Fungal Proteins / genetics
  • Genetic Variation*
  • Lichens / classification*
  • Lichens / cytology
  • Lichens / genetics
  • Molecular Sequence Data
  • Phylogeny
  • Sequence Alignment
  • Sequence Analysis, DNA


  • DNA, Fungal
  • DNA, Ribosomal Spacer
  • Fungal Proteins