Entoloma jahnii , a rare species in Europe

The author describe two localities of Entoloma jahnii Wolfel & Winterh., which were found during the mycocoenological research in Pomerania and Wielkopolska Regions in the phytocoenoses of Carici elongatae-Alnetum and Galio sylvatici-Carpinetum associations. The article consists of a description of gathered specimens and some remarks concerning ecology of this rare species.

intRoDuCtion Entoloma jahnii is one of three members of section Claudopus in Poland (Wojewoda 2003), which are characterized by pleurotoid or omphalinoid basidiocarps and excentric or absent stipe.
It was described for the first time from Germany by Wölfel and Winterhoff (1993).since then it was rarely found in several other european countries.in Poland this species was found in two localities: Lipka forest inspectorate (Pomerania Region) and krajkowo nature reserve (Wielkopolska Region). the aim of this paper it to contribute to the present knowledge on distribution and ecology of this species.the collections were deposited at the Herbarium of the Department of Plant ecology and environmental Protection (PozM), the adam Mickiewicz university, Poznań.

ResuLts
The description refers to specimens from the first locality.Characteristic features of the collected carpophores agree essentially with diagnoses given by noordeloos (2004).
Stipe 1-3 mm long, 0.5-1 mm wide, excentric, sometimes rudimentary, bent, white and hairy. in the upper part slightly widened, at the base with long mycelium, which covers the substrate radially from the point of attachment.
in Lipka forest inspectorate during summer and autumn visits carpophores of Entoloma jahnii were observed on a rotten log of Betula (leg.J. nita).they were growing on the underside of the log, which was soaked in the boggy bottom, just after a periodical flood.The number of carpophores varied during the observation period of 3 years (8 visits) from 1 to over 100.During two observations carpophores of Entoloma jahnii were accompanied by Pluteus podospileus.
in krajkowo reserve ten carpophores of this species were found on the small piece of wood which was part of an old and well decayed log of probably Quercus robur or Carpinus betulus lying on the ground among the Dryopteris filix-mas and other plants.this was the moistest part of the plot.no other species of fungi were found on this piece of wood. the species was found only once, on July 29th 2009 (leg.M. stefaniak).

DisCussion
until recently, Entoloma jahnii has been reported from Poland only from the locality in Lipka inspectorate forest.krajkowo nature reserve is the second locality of this species.
This saprotrophic species has been noted in Germany (Krieglsteiner 2003), Belgium (noordeloos 2004), Denmark (Laessøe 2008), finland (noordeloos 2008), sweden (Ludwig 2007) and in the British isles (schafer 2008), where it was found on barked, rotten wood of frondose tree species: Alnus, Betula, Populus, Fraxinus and Quercus.The species is regarded to be confined to moist and dry deciduous forests and copses (noordeloos 2004).it also shows the association with frondose tree species.this species was found by the authors in two forest associations which offer different ecological conditions, the main differences are moisture conditions and availability of wood of different tree species.the locality in Lipka forest inspectorate was temporarily flooded, whereas Krajkowo nature reserve is rather dry and never flooded.The first locality offered also different substrates (Alnus glutinosa, Betula sp.) compared to krajkowo nature reserve (Quercus robur, Carpinus betulus, Ulmus leavis).
the localities show full scale of substrates and ecological conditions in which this species can occur -from moist to mesophilous forest associations.Entoloma jahnii is red-listed in the Mecklenburg-Vorpomernn region (schwik et al. 1999), andin Denmark (the Danish Red Data Book 2010).fruitbodies of this species are frequently found in hidden places, such as the underside of logs, branches, or pieces of wood (noordeloos 2004), and can be easily overlooked.this feature seems to be one of the reasons of its rarity, nevertheless in our opinion this species is really rare in Poland. in recent years many studies on macrofungi were conducted in broadleaved forests and copses (e.g., Bujakiewicz 1989;Bujakiewicz et al. 2005;Bujakiewicz, stefaniak 2009;Friedrich 1994;Kujawa 2009;Lisiewska, Malinger 2001;Ławrynowicz et al. 2002;nita, Bujakiewicz 2005) in which, according to literature and the author's own observations suitable ecological conditions occur; still the species is known only from two localities.in our opinion it would be appropriate to include this species on the Polish Red List (Wojewoda, Ławrynowicz 2006) with the category e.
fig. 3. Microscopic elements of E. jahnii: spores (a), capitate and cylindrical hyphae on the stipe (B) and the cap (C) surface.