The genus Parmelina (Parmeliaceae) in the Russian Caucasus

Abstract

The present study provides a brief survey of the genus Parmelina in the Russian Caucasus (Western Transcaucasia, Western, Central and Eastern Caucasus) with a special emphasis on species distribution. The study area is located in the largest nature reserves of the Russian Caucasus — Kavkazskiy, Utrish, Severo-Osetinskiy, Erzi. This paper contributes to a better understanding of the genus in the Caucasus, focusing mainly on the author’s collections in different regions of the Northern Caucasus in 2008–2016. Four species have been identified from the Russian Caucasus — Parmelina carporrhizans, P. pastillifera, P. quercina and P. tiliacea. Notes on their morphology, anatomy, ecology and distribution are based on data obtained from a study of ca. 20 specimens of each species. The presence of whitish macules on the upper surface of P. carporrhizans (after Clerc, Truong, 2008) as an important diagnostic feature was shown. The Caucasian material shows the differences in size and proportions of ascospores, size and shape of pycnoconidia between critical species P. carporrhizans and P. quercina. An identification key for Caucasian Parmelina species is composed for the first time and can be used for central regions of Russia.