Rhizoplaca porterii S. Leavitt, F. Fernandez-Mendoza , Lumbsch, Sohrabi & L. St. Clair

Leavitt, Steven D., Fernandez-Mendoza, Fernando, Perez-Ortega, Sergio, Sohrabi, Mohammad, Divakar, Pradeep K., Lumbsch, H. Thorsten & Clair, Larry L. St., 2013, DNA barcode identification of lichen-forming fungal species in the Rhizoplaca melanophthalma species-complex (Lecanorales, Lecanoraceae), including five new species, MycoKeys 7, pp. 1-22 : 11-12

Rhizoplaca porterii S. Leavitt, F. Fernandez-Mendoza, Lumbsch, Sohrabi & L. St. Clair sp. nov.

Type.

USA, Utah, Wayne County, Thousand Lakes Mountain, vicinity of 'Flat Top’, near summit, 38.4432°N, 111.4703°W, on basalt, 3400 m alt., October 1997, Lyndon D. Porter BRY-C55096 (holotype BRY).

Description.

Morphologically similar to Rhizoplaca melanophthalma sensu stricto, but consists of specimens recovered within 'clade IVd’ 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 also characterized by the absence of a group I intron in the nuclear SSU rDNA at the 1516 position ( Gutiérrez et al. 2007), which is present in all other species within the Rhizoplaca melanophthalma species-complex. The mean genetic distances among ITS haplotypes was estimated to be 0.002 ± 0.002.

Chemistry– Usnic acid (major); usually with psoromic (major), constipatic (minor), dehydroconstipatic (minor), dehydroprotocetraric (minor), subpsoromic (minor), demethylpsoromic (minor), and 2'-O-demethylsubpsoromic (minor or trace) acids.

Reference phylogeny.

Leavitt et al. 2011a (fig. 5, 'clade IVd’).

Reference sequences.

GenBank Nos. HM577327 (ITS), HM57710 (IGS), HM577461 (MCM 7), and HM576971 (β-tubulin).

Phylogenetic notes: A monophyletic lineage in both concatenated multilocus gene tree with weak statistical support (ML bootstrap < 50%; posterior probability < 0.5), and with strong statistical support in the ITS gene topology (ML bootstrap = 94%, this study); and strong speciation probability inferred from multiple loci (BPP speciation probability ≥ 0.97). Rhizoplaca porterii belongs to a closely related, and well-supported, monophyletic lineage including Rhizoplaca occulta , Rhizoplaca parilis , Rhizoplaca porterii , and the obligatory vagrant species Rhizoplaca haydenii and Rhizoplaca idahoensis .

Ecology and distribution.

This species usually occurs on exposed calcium-poor rock (e.g. basalt, granite, schist), but sometimes on calcium rich sandstone and limestone. Its habitat ranges from pinyon-juniper woodland into montane coniferous forests and lower alpine tundra. This taxon iscurrently known only from the western USA (Idaho and Utah).

Etymology.

The new taxon is named in honor ofDr. Lyndon D. Porter, whose research on Rhizoplaca melanophthalma proved invaluable to the present work.

Specimens examined.

See supplementary file 1.