Crittendenia coppinsii (P. Roberts) Diederich, M. Westb., Millanes & Wedin comb. nov.

MycoBank number: MB 835606; Index Fungorum number: IF 835606; Facesoffungi number: FoF;

Basionym: Chionosphaera coppinsii P. Roberts, Mycotaxon 63, 195 (1997); type: Scotland, Wester Ross, Torridon, Inveralligan, wood & gorge of Abhainn Alligin, on Melanelixia glabratula, 21 vi 1994, B. J. Coppins 16400 & A. M. O’Dare (E—holotype, non vid.; K 39188—isotype!).

A detailed description of this species is provided by Roberts (1997). Crittendenia coppinsii was originally described from the UK (Scotland) and the type grows on Melanelixia glabratula (Roberts 1997). A second specimen provisionally reported by P. Roberts (1997) and growing on Lecidella elaeochroma was later assigned to C. lichenicola by Kirschner et al. (2001). Coppins et al. (2009) also found C. coppinsii on a new host, Melanelixia subaurifera. Here we report Crittendenia coppinsii as new to Belgium, Norway, Sweden and Switzerland, based on specimens examined by us that grow on Melanelixia glabratula, Melanohalea exasperata and M. exasperatula. A record of ‘Chionosphaera cf. apobasidialis’ from Russia on Melanohalea olivacea is further accepted as belonging to C. coppinsii because the description fully agrees with C. coppinsii s. str. and the host is a species of Melanohalea (Zhurbenko & Himelbrant 2002). Crittendenia coppinsii should be actively searched for on other species of Melanelixia and Melanohalea.

Additional specimens examined. Belgium: Liège: Eupen, between road N68 and N620, 50°35′N, 6°2.5′E, 420 m, 2016, van den Boom 54983 (hb. van den Boom).—Norway: Møre og Romsal: Halsa, S-facing slope by Halsafjorden, Kalsetlia, 100 m, 2000, Holien 8105 (TRH); Rama, the Romsdalen Valley, S of Trollveggen Camping by the River Rauma (WP54), 6 vi 2017, Westberg & Olsson s. n. (UPS).—Sweden: Uppland: Vänge, Fiby Urskog Nature Reserve, southernmost part near entrance, 59° 52.9′N, 17°21.15′E, 7 iv 2016, Westberg (S, UPS F-805352); ibid., 8 iv 2016, Westberg, Ekman & von Hirschheydt (UPS F-796396); ibid., NE of the nature reserve, 59°53.4′N, 17°21.6′E, 7 iv 2017, Westberg (S, UPS F-805353).—Switzerland: Bern:Lenk, Zelg, Simmenfälle, 1030 m, 2017, Zimmermann 1946 (hb. Zimmermann). Schwyz: Muotathal, E Fruttli, Flaschenwald, 1240 m, 1989, Groner 714 (hb. Groner).