Analysis of lichen secondary chemistry doubled the number of Cetrelia WL Culb. & CF Culb. species (Parmeliaceae, lichenised Ascomycota) in Hungary

The distribution patterns of lichen secondary metabolites are often taxon specific. They represent cryptic chemical diversity additional to morphological-anatomical biodiversity. Cetrelia W.L. Culb. & C.F. Culb. species (c. 200 specimens) were checked and revised by thin-layer chromatography. Soredia, pseudocyphellae, rhizines, features of lower surface are the main morphological characters analysed against the presence of cortical pigment, atranorin and medullary alpha-alectoronic acid, anziaic acid, alpha-collatolic acid, beta-alectoronic acid, beta-collatolic acid, imbricaric acid, 4-O-dcmethylimbricaric acid, olivetoric acid, perlatolic acid, physodic acid and 4-O-methylphysodic acid. The European occurrence of C. chicitae (W.L. Culb.) W.L. Culb. & C.F. Culb. - described from America - is confirmed on the basis of identical secondary metabolite composition by seven lichen substances. Four species were revealed and mapped in Hungary. Cetrelia chicitae and C. monachorum (Zahlbr.) W.L. Culb. & C.F. Culb. are new for the Hungarian lichen flora. From the originally known two taxa C. cetrarioides (Delise) W.L. Culb. & C.F. Culb. proved to be rare, C. olivetorum (NyL) WL. Culb. & C.F. Culb. is less frequent than regarded earlier. Currently C. monachorum is the most frequent Cetrelia species in Hungary. Cetrelia chicitae and C. cetrarioides may need protection measures. Parmelia cetrarioides f. pseudofallax (Gyeln.) Gyeln. is lectotypified here.

Automated summary

The distribution patterns of lichen secondary metabolites are taxon specific, showing additional chemical diversity apart from morphological-anatomical biodiversity. This study identified four Cetrelia species, with Cetrelia chicitae and C. monachorum being new additions to the Hungarian lichen flora, with the latter being the most common species in Hungary. Protection measures may be needed for C. chicitae and C. cetrarioides.