An appropriate fungus to assess
Current name: Hericium flagellum (Scop.) Pers.
Synonyms: Hericium alpestre Pers.
Molecular analysis of nearly 70 ITS sequences of 6 different Hericium spp. originating from Europe (including the Caucasus), East Asia (Japan, Korea, China, Malaysia), North America (USA, Canada) and (South America (Argentina) revealed that H. alpestre (current name H. flagellum) seems to constitute a paraphyletic taxon and that ITS sequences are very similar to H. americanum; the morphology of these two species is also highly similar (Hallenberg et al. 2013). However, all the samples of the former species originated from Europe and Caucasus (Krasnodar, Russia), and all were collected on Abies. The latter species is well-known from eastern parts of North America, typically growing on hardwood and occasionally on Tsuga. According to this study, the only but clear difference between H. alpestre and H. americanum seems to be the occurrence on hardwood and distribution limited to North America versus coniferous wood and Europe. More research is needed to elucidate this relation as well as the intraspecific variation of H. flagellum. Taking into account well-established delimitation of this species in the European literature (e.g. Bernicchia and Gorjón 2010), for the present evaluation of the global threats and conservation status, H. flagellum is considered to be the European species, the same across the whole Europe and Caucasus, and highly host-dependent on silver fir (Abies alba).