Phylogenetic study and taxonomic revision of the Xanthoparmelia mexicana group, including the description of a new species (Parmeliaceae, Ascomycota)

By

Bárcenas-Peña, Alejandrina
Leavitt, Steven Don, 1979-
Huang, Jen-Pan
Grewe, Felix
Lumbsch, Thorsten

Type

Article

Date of Publication

2018-9-18

Original Publication

NeoBiota : advancing research on alien species and biological invasions

Volume

40

Pages

13--28

Subjects

cryptic species , lichenised fungi , Mexico , Phylogeny , taxonomy

Contributed by

Pensoft Publishers

Language

English

Published by

Sophia, Bulgaria Pensoft Publishers

Identifiers

DOI: https://doi.org/10.3897/mycokeys.40.26724

 

Abstract

Xanthoparmelia(Parmeliaceae, Ascomycota) is the most species-rich genus of lichen-forming fungi. Species boundaries are based on morphological and chemical features, varying reproductive strategies and, more recently, molecular sequence data. The isidiateXanthoparmeliamexicanagroup is common in arid regions of North and Central America and includes a range of morphological variation and variable secondary metabolites – salazinic or stictic acids mainly. In order to better understand the evolutionary history of this group and potential taxonomic implications, a molecular phylogeny representing 58 ingroup samples was reconstructed using four loci, including ITS, mtSSU, nuLSU rDNA and MCM7. Results indicate the existence of multiple, distinct lineages phenotypically agreeing withX.mexicana.One of these isidiate, salazinic acid-containing lineages is described here as a new species,X.pedregalensissp. nov., including populations from xerophytic scrub vegetation in Pedregal de San Angel, Mexico City.X.mexicanas. str. is less isidiate thanX.pedregalensisand has salazinic and consalazinic acid, occasionally with norstictic acid; whereasX.pedregalensiscontains salazinic and norstictic acids and an unknown substance. Samples from the Old World, morphologically agreeing withX.mexicana, are only distantly related toX.mexicanas. str. Our results indicate thatX.mexicanais likely less common than previously assumed and ongoing taxonomic revisions are required for isidiateXanthoparmeliaspecies.