The occurrence of Amanita strobiliformis (Paulet ex Vittad.) Bertill. in Szczecin and its distribution in Poland

Results of long-term research into the occurrence of Amanita strobiliformis in Szczecin are presented. Five new localities of the species are described and its distribution in Poland is discussed.


INTRODUCTION
Amanita strobiliformis is a thermophilous and calciphilous species that forms symbiosis primarily with deciduous trees, mostly of the genera Fagus, Quercus, Betula and Tilia, less frequently with coniferous trees: Pinus and Picea.It is widespread and occurs in Australia, East and Central Asia, North America, North Africa and Europe.In Europe, it occurs more frequently in the south and its northern limit reaches southern Scandinavia but does not exceed 60° latitude (Krieglsteiner 2003).
Amanita strobiliformis was thought to be extinct in Poland (Wojewoda, Ławrynowicz 1992) as it was initially known only from Tomaszów Lubelski (Błoński 1896) and from Elbląg (Nitardy 1904).The herbarium specimen from the Elbląg locality is not available and Skirgiełło (1972) suggested it might have been a determination error.The species has been recorded by several authors at scattered localities throughout Poland since the mid 1990s and is included as a rare species (R) on the current red list of fungi (Wojewoda, Ławrynowicz 2006).
The occurrence of Amanita strobiliformis in Szczecin between 1997 and 2012 is characterized below.Five new localities recorded in the years 2007-2011 are presented and the current distribution of the species in Poland is discussed.

MATERIALS AND METHODS
Amanita strobiliformis was reported from the Dendrological Garden in Szczecin where it was first recorded in 1997 (Friedrich, Orzechowska 2002;Friedrich 2011).It was the sixth locality of the species in Poland.Both the locality and the Dendrological Garden was systematically observed after the first record for the occurrence of mycobiota.Fruit bodies of Amanita strobiliformis were counted every year and the geographical position of the occurrence sites was determined in the field and mapped.A spread of Amanita strobiliformis from the initial site and an increased range were recorded.Fruit bodies occurred only at one site covering an area of ca.20 m 2 in the first four years (site 1).They were also recorded outside site 1 in the following years and occurred at a total of twelve field sites throughout the study.They grew at nine sites in the Dendrological Garden in Szczecin and its immediate vicinity in the final year (2012).At present the occurrence area of Amanita strobiliformis resembles a triangle 560 × 580 × 350 m and is regarded as one locality comprising twelve sites in the discussion.The farthest points from site 1 are 180 m westwards, 410 m north-eastwards and 350 m eastwards.The distance between adjacent sites of this vast locality is between 20 and 50 m.

THE LOCALITY IN THE DENDROLOGICAL GARDEN IN SZCZECIN
The locality: characteristic features.Site 1 of the locality where Amanita strobiliformis has fruited every year since 1997 is in the south-east corner of the Dendrological Garden and is surrounded by a small stone wall on three sides.The wall borders on an asphalt park alleyway, a street Słowacki and the premises of the West Pomeranian University of Technology (formerly Agricultural Academy).
An old tree stand which remains after a former cemetery stand consists of Quercus robur, Tilia cordata, Acer pseudoplatanus, Platanus × hispidus and Pseudotsuga menziesii.Fruit bodies of A. strobiliformis occurred between two oaks and a lime tree.The stand belongs to forest communities of the class Querco-Fagetea but only Aegopodium podagraria, Ficaria verna and the moss Plagiomnium undulatum were recorded.The forest floor is not dense.As well as the above species, it mostly comprises species of synanthropic communities of the class Artemisietea (Alliaria petiolata, Anthriscus sylvestris, Chaerophyllum temulum, Galium aparine, Geranium robertianum, Geum urbanum, Viola odorata) and Stelarietea (Lapsana communis, Veronica hederifolia) and species of meadow communities of the class Molinio-Arrhenatheretea (Achillea millefolium, Arrhenatherum elatius, Bellis perennis, Ceratium holosteoides, Dactylis glomerata, Festuca pratensis, Poa pratensis, Taraxacum officinale, Trifolium pratense, T. repens).These species are accompanied by Allium vineale, Hedera helix, Moechringia trinervia, Plantago major, Poa annua and Veronica chamaedrys.The forest floor is mown, usually twice every year.This sometimes contributes to the destruction of fungal fruit bodies.The litter of varying thickness and single specimens of few species of herbaceous plants and moss species occur at other sites outside site 1 on the lawn in the West Pomeranian University of Technology.
New localities.Five new localities of Amanita strobiliformis scattered across Poland were recorded between 2007 and 2011.Three are in various beech communities while the other two are in a city park and a dendrological garden.The localities are characterized below in the order they were reported.They are positioned in relation to the nearest village or town in the ATPOL grid (Zając 1978) modified for mycology by Wojewoda (2000), in geographic mesoregions (Kondracki 2002) and in voivodeships.The numbering of localities corresponds to the numbering in Figure 4 which also presents localities known from the literature.
Przelewice (Fig. 4 -locality 9).ATPOL Ca-16, Równina Pyrzycko-Stargardzka plain (313.31),West Pomeranian voivodeship.The locality of Amanita strobiliformis in Przelewice was recorded during long-term systematic research into the mycobiota of the Dendrological Garden.A total of 14 fruit bodies were observed over three years (18.06.2007, 19.07.2007, 08.07.2009, 10.08.2009, 12.07.2010, 20.07.2011).They grew at four different sites less than a hundred meters apart.The majority of fruit bodies grew near Fagus sylvatica and Fraxinus exscelsior, and two near Betula lutea, Prunus serotina and Malus sp.Six fruit bodies were destroyed by people despite the monitoring in the Garden.
Węgorzewo (Fig. 4 -locality 7).ATPOL Fb-00, Kraina Wielkich Jezior Mazurskich (Great Masurian Lakes Region, 842.83),Warmia and Mazury voivodeship.This locality of Amanita strobiliformis was recorded during a holiday stay in Węgorzewo on 27.07.2009.It is in the Helwing Park, near Generała J. Bema street and a few meters from a park alleyway.Three developing fruit bodies grew on a lawn near Tilia cordata, just outside the reach of the crown.
Giebło .ATPOL Df-17, Wyżyna Częstochowska upland (341.31),Silesian voivodeship.The locality of Amanita strobiliformis was recorded in the Las Niwiski forest in Giebło village near Ogrodzieniec, ca.6 km NW of the Pilica river.Fagus sylvatica-Cruciata glabra forest community occurs at the locality.One fruit body was recorded on the soil under Fagus sylvatica in September 2008 and2009 (leg. et det. D. Karasiński).One fruit body was destroyed by mushroom pickers.

DISCUSSION
Amanita strobiliformis was recorded in Poland only at five localities in the 20 th century.It was noted for the first time after a period spanning a few decades in 1967 (Bujakiewicz, Lisiewska 1983).It is not clear whether the species did not occur (did not develop fruit bodies) in Poland or whether it was not observed for various reasons for such a long time in the 20 th century.Some 90 localities were recorded in Germany (Krieglsteiner 1991) in similar physiogeographic conditions (between 50° and 55° latitude) in the same period.
One of the reasons for this may be that mycological research in Poland was mostly conducted in natural forests, national and landscape parks, nature reserves while this species often occurs in parks and anthropogenic areas in Poland.Descriptions of localities of Amanita strobiliformis in Poland available in the literature show that half of the localities are in park-like anthropogenic tree patches, e.g. the Botanical Garden in Poznań, Dendrological Gardens in Szczecin and Przelewice, city parks in Poznań, Węgorzewo and Gdańsk.Fruit bodies usually occur under Fagus sylvatica, less frequently under Quercus sp., Tilia sp. and Betula pendula.As fruit bodies develop in parks, in noticeable places, they are destroyed by people, as noted by authors such as Wilga (2005) and Kudławiec (2008Kudławiec ( -2011)).
At present a total of 22 localities, including the new localities described here, in 19 ATPOL 10x10 km squares are known in Poland (Fig. 4).Approximately half of them have been reported by non-professionals in the last ten years.Amateur fungal groups importantly contribute to the recognition of the distribution of fungi in Poland, also rare and threatened species.
Fruit bodies were produced between June and October at the localities in Poland.This was also the period when fruit bodies were observed at the locality in the Dendrological Garden in Szczecin over a period of 16 years.A detailed seasonal rhythm of fruit body production at this locality is similar to the results of studies in Germany (Baden-Württembergs) but the fruiting peak begins a month earlier (Krieglsteiner 2003).One-time data on the occurrence of Amanita strobiliformis which usually produced only single fruit bodies (1-3) are reported from the majority of Polish localities.The most abundant localities where Amanita strobiliformis produces annually from over ten to over fifty fruit bodies are the Dendrological Garden in Szczecin and the Park Sołacki park in Poznań, where a total of over 50 fruit bodies were observed over four consecutive years (Kudławiec 2008(Kudławiec , 2009(Kudławiec , 2010(Kudławiec , 2011)).