Rhizoplaca polymorpha S. Leavitt, F. Fernández-Mendoza, Lumbsch, Sohrabi & L. St. Clair

Rhizoplaca polymorpha consists of specimens recovered within ‘clade IVc’ in Leavitt et al. (2011a), which is supported as a lineage distinct from all other populations according to coalescent-based genetic analysis of multiple genetic loci. This species is morphologically quite variable. While some individuals are morphologically similar to Rhizoplaca melanophthalma sensu stricto, vagrant forms partly embedded in badland soils in western Idaho also belong within this species. The mean genetic distance among ITS haplotypes was estimated to be 0.0 ± 0. Chemistry– Usnic (major), constipatic (minor), dehydroconstipatic (minor), 2’-O-demethylsubpsoromic (minor or trace) and 2’-O-demethylpsoromic (minor) acids; occasionally with dehydroprotocetraric (minor) and psoromic acid (major).