Mycobiont and photobiont DNA barcoding revealed polymetallic rocks to be a rich source of specific lichen diversity

The main goal of the present study is to investigate the diversity of mycobionts and photobionts of rock-inhabiting lichens in pyrite-bearing schist outcrops in the Rudawy Janowickie Mts of the Sudety Mountains, also known as the Coloured Lakelets. Morphological, chemical, and molecular methods were used to determine lichen samples. A total of 41 lichen taxa were found in the study area, and 116 nuITS mycobiont sequences were obtained. The presented data constitute the first molecular evidence of the occurrence of almost all these taxa in Poland (except Sagedia mastrucata), as well as the first sequences of Lecanora handelii, L. subarea, and Porpidia superba, which were deposited and shared in GenBank. One species, Lepraria pseudocaesiella, is described here as new to science, based on morphological, chemical, and molecular evidence. Myriospora rufescens is new to Poland, and the first Polish contemporary record of Trapelia elacista is presented. In case of photobionts, we obtained 64 nuITS sequences, and they belong to the genera Asterochloris, Trebouxia, and Pseudochlorella. This included the first evidence of an association between Rhizocarpon s.l. and Asterochloris. To illustrate the relationships between the mycobiont and photobiont genotypes detected on polymetallic rocks, we used a haplotype network tool. Haplotype network analyses for mycobionts resulted in the discovery of 20 new haplotypes from 12 lichen species. For photobionts, most of our sequences clustered into dominant and previously reported haplotypes.