Petrova O. The lichen genus Usnea in eastern Gennoscandia. III Shrubby species. Ann. Bot. Fennici. 1999, 36, p. 235-256.

236 Halonen • ANN. BOT. FENNICI 36 (1999) and nomenclature of the genus turned out to be very difficult, its thorough treatment was avoided by most lichenologists. Hakulinen (1963) reduced the number of Finnish species to 25 (plus seven varieties) and Carlin and Swahn (1977) made an attempt to establish a new taxonomy for the Swed- ish species. Bystrek (1994a) published a synopsis of the European Usnea , but because he essentially follows Motyka, we regard most of his species concepts untenable. Only Clerc (e.g., 1987a, 1997) started a serious revision of the genus Usnea in the Northern Hemisphere. Aproject to revise the Usnea material collected from East Fennoscandia was started in 1993. The study area consists of Finland and the northern part of the Leningrad Region, the Republic of Ka- relia and the Murmansk Region in Russia (Fig. 1). The study has resulted in some earlier publica- tions (Myllys 1994, Halonen & Puolasmaa 1995, Halonen 1997). A treatment of the pendent spe- cies, excluding Usnea longissima , is still under preparation. Based on the work of our project, Viti- kainen et al. (1997) provisionally reported 13 spe- cies of Usnea from Finland, reducing most of the taxa recognized by Räsänen to synonymy. As to Russian Fennoscandia, Dombrovskaya (1970) reported five species of Usnea from the Murmansk Region. Based on Motyka’s identifi- cations Ahlner (1937; overlooked by Dombrovs- kaya) reported seven more species, with four sub- species and one variety, from the present Mur- mansk Region (under Salla and Petsamo). Golub- kova (1996) reported five species for the Mur- mansk Region, 15 species for the Republic of Ka- relia and five species for the Leningrad Region (her “widespread” species were considered to be present in all the three areas). Fadeeva et al. (1997) recognized only 10 species from the Republic of Karelia. Most of the species treated here were classi- fied by Bystrek (1994a) as belonging to Usnea subg. Usnea sect. Barbata subsect. Subfloridana Bystrek (incorrect renaming of subsect. Comosae Motyka) or subsect. Silesiaca Bystrek. Usnea hirta was placed in sect. Foveata Motyka, however, and Usnea glabrata in sect. Glabrata Motyka. We think that his classification is very artificial and it also contains numerous nomenclatural errors. Fig. 1. The biogeographical provinces. Finland : 1 Åland (Alandia, Al), 2 Varsinais-Suomi (Regio aboën- sis, Ab), 3 Uusimaa (Nylandia, N), 4 Etelä-Karjala (Ka- relia australis, Ka), 5 Satakunta (St), 6 Etelä-Häme (Tavastia australis, Ta), 7 Etelä-Savo (Savonia aus- tralis, Sa), 8 Laatokan Karjala (Karelia ladogensis, Kl), 9 Etelä-Pohjanmaa (Ostrobottnia australis, Oa), 10 Pohjois-Häme (Tavastia borealis, Tb), 11 Pohjois-Savo (Savonia borealis, Sb), 12 Pohjois-Karjala (Karelia bo- realis, Kb), 13 Keski-Pohjanmaa (Ostrobottnia media, Om), 14 Kainuu (Ostrobottnia kajanensis, Ok), 15 Ou- lun Pohjanmaa (Ostrobottnia ouluensis, Obo), 16 Perä- Pohjanmaa (Ostrobottnia ultima, Obu), 17 Koillismaa (Regio kuusamoënsis, Ks), 18 Kittilän Lappi (Lapponia kittilensis, Lkk), 19 Sompion Lappi (Lapponia sompien- sis, Lks), 20 Enontekiön Lappi (Lapponia enontekien- sis, Le), 21 Inarin Lappi (Lapponia inarensis, Li). Rus- sia : Leningrad Region: 1 Karelia australis (Ka, Rus- sian side), 2 Isthmus karelicus (Ik); Republic of Karelia: 3 Karelia ladogensis (Kl, Russian side; southernmost parts located in the Leningrad Region), 4 Karelia olo- netsensis (Kol), 5 Karelia borealis (Kb, Russian side), 6 Karelia onegensis (Kon), 7 Karelia transonegensis (Kton), 8 Karelia pomorica occidentalis (Kpoc), 9 Kare- lia pomorica orientalis (Kpor), 10 Regio kuusamoënsis (Ks, Russian side; northernmost parts located in Mur- mansk Region), 11 Karelia keretina (Kk, northernmost parts located in the Murmansk Region); Murmansk Re- gion: 12 Lapponia Imandrae (Lim), 13 Lapponia Varsu- gae (Lv), 14 Lapponia ponojensis (Lp), 15 Lapponia petsamoënsis (Lps), 16 Lapponia tulomensis (Lt), 17 Lapponia murmanica (Lm).