Absence of anthraquinone pigments is paraphyletic and a phylogenetically unreliable character in theTeloschistaceae

Abstract

AbstractIt has been suggested that the absence of anthraquinones is not a synapomorphic character, but appears independently in unrelated lineages ofTeloschistaceae. We analyzed ITS nrDNA regions in species of the genusCaloplacaand present evidence for five such examples: theCaloplaca cerinagroup,C. obscurella, theC. servitianagroup, theC. xericagroup and theC. variabilisgroup (Pyrenodesmia). In some cases, loss of anthraquinones is observed only in individuals within ordinarily pigmented populations, but sometimes the loss covers whole lineages containing one or more species. Both situations are observed in theC. servitianagroup. Loss of anthraquinones is always followed by the synthesis of ‘alternative’ pigments (oftenSedifolia-grey). In the specimens with anthraquinone-containing apothecia studied, these pigments are not visible in apothecial sections after dissolving anthraquinones in K. Fully unpigmented apothecia have not been observed.TheCaloplaca xericagroup is a newly established, infraspecific grouping of species related to, and similar to,C. xerica. TheCaloplaca servitianagroup is also newly established and represents an isolated lineage covering two rather different, but related species.Caloplaca neotauricais described here as a new species with apothecia of two colour variants; orange-red (with anthraquinones) and grey (withSedifolia-grey).The genusHuearepresents another taxon lacking anthraquinones withinTeloschistaceae. The generaApatoplacaandCephalophysis, which lack anthraquinones, are tentatively placed inTeloschistaceae, but their phylogenetic identity has not been recognized.Hueideais reported to have no anthraquinones, but its secondary metabolites should be studied further and its possible placement inTeloschistaceaeassessed.We suggest thatCaloplaca abbreviatavar.lecideoidesandC. celatarepresent variants ofC. stillicidiorumlacking anthraquinones.