Image of Annulohypoxylon cohaerens

Description:

Slo.: ? - syn.: Sphaeria cohaerens Pers., Hypoxylon cohaerens (Pers.) Fr., Hypoxylon rutilum var. ericae Gonz. Frag., Hypoxylon atrorufum Ellis & Everh. - Habitat: steep mountain slope, south-southeast aspect, calcareous ground, open place, full sun, exposed to direct rain, average precipitations ~ 3.000 mm/year, average temperature 5-6 deg C, elevations 830 m (2.700 feet), alpine phytogeographical region. - Substratum: cut down Fagus sylvatica trunk lying on ground, on bare wood. - Comments: First I thought I found some species of genus Hypoxylon. The problem was, as I wrongly thought, they grew exclusively on tree bark, not on wood directly (most frequently they do so, but not exclusively). Therefore I considered genus Kretzschmaria, possibly not yet mature and common Kretzschmaria deusta. I know bright whitish-gray anamorph of it and quite common mature completely black stroma. But I've never found something in between. Only after consulting AscoFrance, Mr. Enrique Rubio the pictures were determined as Annulohypoxylon cohaerens (former Hypoxylon cohaerens). Genus Annulohypoxylon was separated from genus Hypoxylon in 2005. Actually subglobose, somewhat flattened above, confluent, at first brown, stroma with papillate ostioles fit well to this determination although the fungus is not yet fully mature. This fungus is an inhabitant of beech and it appears on bare wood as well as on bark. It often grows together with similar Hypoxylon fragiforme, which is a very common species in our woods. Extraction of pigments by KOH and microscopy would make this determination crystal-clear. But this was not done. The discussion about this find on Asco France forum can be reached here: http://www.ascofrance.com/forum?page=1 (search for 'Kretzschmaria deusta ?'). - Ref.: (1) Personal communication with Mr. Lothar Krieglsteiner, Thomas Lsse and Peter Pwert. Id'ed by Mr. Enrique Rubio, Asco France, http://www.ascofrance.com/forum?page=1 (2) http://pyrenomycetes.free.fr/hypoxylon/html/Hypoxylon_cohaerens.htm