Exidia cinnamomescens Raitv.

Abstract

Exidia cinnamomescens Raitv., Tartu Riikliku Ülikooli Toimetised 136: 208, 1963 = Myxarium cinnamomescens (Raitviir) Raitviir, Plants and Animals of the Far East: 113, 1971. Holotype. Russia • Komi Rep.: Syktyvdinsky Dist., Graddor, Populus tremula (fallen log), 8 Aug 1957, Põldmaa (TAAM 5995 *, studied). Note. This species was first described as a member of Exidia (Raitviir 1963) and later combined in Myxarium (Raitviir 1971). It was accepted as M. cinnamomescens in our recent publications (Spirin et al. 2018, 2019, 2025). The species name was associated with a sister species of M. populinum (P. Karst.) Spirin & Malysheva, inhabiting various angiosperm hosts in temperate and boreal forests of Eurasia. The two species have been separated almost exclusively based on their spore size (mainly the spore width). The basidiospore dimensions from the type specimen of E. cinnamomescens fall within the same range with other specimens so labelled, (9.3 –) 10.2–13.4 (– 13.7) × (4.0 –) 4.1–5.3 (– 5.8) μm (n = 30 / 1), L = 11.88, W = 4.75, Q = 2.52. Those latter specimens were used by us for DNA studies. However, the ITS sequence newly obtained from the type specimen of E. cinnamomescens shows that it is conspecific with M. populinum. It means that the species named as M. cinnamomescens in our previous publications needs a new species epithet. There are four names for the European exidioid Myxarium spp. which had remained unaddressed in our earlier studies, i. e. Tremella gemmata Lév., Exidia corrugativa Bref., Tremella ilicis Boud., and Exidia alboglobosa Lloyd. The type material of T. gemmata (in PC, studied) belongs to M. hyalinum as typified and redescribed in Spirin et al. (2018). As far as we know, no extant material exists for E. corrugativa and T. ilicis. In our opinion, their original illustrations (published by Brefeld 1888; Boudier 1911, correspondingly) again represent M. hyalinum. Finally, the type of E. alboglobosa (BPI 701610, studied) most likely belongs to a sister species of M. nucleatum Wallr., devoid of mineral inclusions (see comments in Spirin et al. 2019: 6–7). This necessitates introducing M. cinnamomescens sensu auct. as a new species:

Authors 13

1. Viacheslav Spirin

   University of Helsinki · Finnish Museum of Natural History

   Affiliation as printed

   Finnish Museum of Natural History, University of Helsinki, PO Box 7, 00014 Helsinki, Finland

2. Vera F. Malysheva

   Komarov Botanical Institute of the Russian Academy of Sciences

   Affiliation as printed

   Komarov Botanical Institute, Prof. Popova str. 2, 197022 St. Petersburg, Russia

3. Nathan Schoutteten

   Universität Hamburg

   Affiliation as printed

   Organismic Botany and Mycology, Institute of Plant Science and Microbiology, Ohnhorststraße 18, 22609 Hamburg, Germany

4. Anton Savchenko Aachen Naturalis Biodiversity Center

   Naturalis Biodiversity Center

   Affiliation as printed

   Naturalis Biodiversity Center, Darwinweg 2, 2333 CR Leiden, Netherlands

5. Bernard Rivoire
   Affiliation as printed

   Société Linnéenne de Lyon, 33 rue Bossuet, 69006 Lyon, France

6. Jan Olsson
   Affiliation as printed

   Österplana Skattegården 2, 53384 Hällekis, Sweden

7. Thomas Læssøe

   University of Copenhagen

   Affiliation as printed

   Globe Institute, Department of Biology, University of Copenhagen, Universitetsparken 15, 2100 Copenhagen Ø, Denmark

8. Leif Ryvarden

   University of Oslo

   Affiliation as printed

   Institute of Biological Sciences, University of Oslo, P. O. Box 1045, Blindern, N- 0316 Oslo, Norway

9. Django Grootmyers

   University of Tennessee at Knoxville

   Affiliation as printed

   Department of Ecology and Evolutionary Biology, University of Tennessee, 1406 Circle Drive, Knoxville, Tennessee 37996, USA

10. Matti Kulju

    University of Oulu

    Affiliation as printed

    Ecology and Genetics Research Unit, University of Oulu, P. O. Box 3000, FI- 90014 Oulu, Finland

11. Josef Vlasák

    Czech Academy of Sciences, Biology Centre

    Affiliation as printed

    Biology Centre, Academy of Sciences of the Czech Republic, Branišovská 31, CZ 37005, České Budějovice, Czech Republic

12. M. Victoria Vignale

    National University of Misiones

    Affiliation as printed

    Instituto de Biotecnología Misiones (InBioMis), Facultad de Ciencias Exactas, Químicas y Naturales, Universidad Nacional de Misiones, Ruta Nacional N 12, km 7.5, Posadas, Misiones, CP 3304, Argentina & Instituto Misionero de Biodiversidad (IMiBio), Ruta Nacional N 12, km 5, Puerto Iguazú, Misiones, CP 3370, Argentina

13. Ilya A. Viner

    University of Helsinki · Finnish Museum of Natural History

    Affiliation as printed

    Finnish Museum of Natural History, University of Helsinki, PO Box 7, 00014 Helsinki, Finland