Noteworthy records of aphyllophoroid fungi in Finland ( Basidiomycota )

We present new records of noteworthy aphyllophoroid fungi, mainly polypores and corticioids in Finland. The following 19 rare or infrequently collected species are presented with notes on their substrates: Amylocorticium subsulphureum, Antrodiella parasitica, Ceraceomyces sulphurinus, Clavaria atroumbrina, Clavaria rosea, Gloeophyllum carbonarium, Hyphodontia flavipora, Junghuhnia fimbriatella, Lindtneria chordulata, Odonticium septocystidia, Peniophorella guttulifera, Perenniporia tenuis, Postia immitis, Repetobasidium vile, Resinicium pinicola, Sidera vulgaris, Tomentella coerulea, Trechispora laevis and Xylodon pruni. We also list 41 aphyllophoroid fungi as new to some sections of the boreal vegetation zone in Finland.


Introduction
So far, there are only a few intensive inventories done in Finland that cover all aphyllophorales. Especially other aphyllophoroid fungi than polypores are time consuming to sample: for example basidiocarps of corticioids are small in size and often they grow underneath a trunk. Therefore they are demanding to find, and most of these species need to be identified with a microscope. Because of low sampling effort, most of these species are poorly known.
The first Finnish checklist of aphyllophoroid fungi was published in 2009 [1]. After this, plenty of biogeographical knowledge has accumulated especially about polypores and corticioids, and new records have been published for example by Kunttu et al. [2][3][4][5][6], Kotiranta and Larsson [7], Kotiranta and Shiryaev [8] and Spirin et al. [9]. In this article we present new records of aphyllophoroid fungi mainly from two larger field works that were conducted in Finland in the southern archipelago and in northern Lapland, but also some sporadic records is included.
We consider two kinds of records: rare or little collected species with five earlier records in Finland and species that are new to some section (subzone) of boreal vegetation zone in Finland.

Material and methods
The records presented in this article come from several inventories in different parts of Finland. Records are mainly made during a period from 2008 to 2013, but some older records are also included due to change of the taxonomical status. These studies are mostly connected to inventories of species assemblages in certain areas or ecological research of polypores and corticioids.
Most of the records come from inventories made by Metsähallitus, Natural Heritage Services. These records are from nature conservation areas where the purpose of the inventory has been to map species living in these areas. The inventory methods have been various. Records are also made in an ecological and biogeographical study that concentrates on polypores and corticioids in the southwestern archipelago of Finland (P. Kunttu, doctoral dissertation in preparation). Some records are made during XXI Nordic mycological congress in Rovaniemi in September 2013. Additional records are also made on field trips by authors during their leisure time.
We use Finnish national uniform grid system (27°E) according to Heikinheimo and Raatikainen [10] for coordinates and the abbreviation UCS refers to Uniform Coordinate System. Biogeographical provinces are according to Knudsen and Vesterholt [11]. Boreal and hemiboreal vegetation zones consist of 11 sections (subzones), which are represented in this article ( Fig. 1) [12,13]. Voucher specimens are deposited in the herbaria of the Nomenclature is mainly according to Kotiranta et al. [1], but names of some species follow Miettinen and Larsson [14] and Bernicchia and Gorjón [15]. Nomenclature of the genus Hyphodontia sensu lato follows Hjortstam and Ryvarden [16]. The Finnish national red-listing evaluation of IUCN standard is according to Kotiranta et al. [17]. The decay stage classification of trunks (1-5) is according to Renvall [18]. Diameter of a trunk is given at the breast height if the trunk has been unbroken and at the base if the trunk has been broken.
Material has been collected, identified or confirmed by several researches that are mentioned in the collecting information. At least five times are mentioned the following researchers: TK = Tapio Kekki, HK = Heikki Kotiranta, MK = Matti Kulju, PK = Panu Kunttu, JP = Jorma Pennanen. Collector is also the identifier if not otherwise stated. Number code after the collectors name or abbreviation of the collector is a personal sampling number of the specimen.   There are three earlier records in Finland: Finström (Alandia), Karjalohja and Tammisaari (Regio aboënsis). Fruitbodies have been found on decorticated Ulmus glabra and twig of Thuja plicata [1].

Discussion
The new records of aphyllophoroid fungi presented in this paper are mainly from expected regions, located near to the earlier known area of their distribution. However, the records of some species are far away from the earlier findings: Clavulina rugosa and Trechispora laevis were found from Lapland in northern Finland but earlier they were known only from southern Finland. This means that the distance between the new and the old localities of these fungi is hundreds of kilometers.
The most remarkable records in this paper are Odonticium septocystidia and Junghuhnia fimbriatella, the second records in Finland. Both species are considered to be rare worldwide, despite that these have been found in many European countries, Russia and North America [15]. Also Ceraceomyces sulphurinus seems to be rare in reality despite the fact that its colorful basidiocarp is easy to notice. Only three records have been made in Finland, and occurrences exist in seven other countries in Europe [15].
In addition to these rarely found species there is only one earlier record in Finland for the following species: Clavaria atroumbrina, Hyphodontia flavipora, Resinicium pinicola, Sidera vulgaris and Tomentella coerulea. Resinicium pinicola seems to occur in maritime areas, all three records in Finland are from the archipelago of the Baltic Sea. Sidera vulgaris is a common species in Estonia, so it is possible that in the future it will become more common in Finland as well. It looks like that Pseudotomentella nigra is a northern species in Finland: all the Finnish records are from Lapland.
The high amount of new information has accumulated after the publication of the Finnish checklist of aphyllophorales [1]. This indicates that the aphyllophoroid fungi are still poorly known in Finland.
In general, for many aphyllophoroid fungi species the few records are from distant geographic locations and it is difficult to imagine that their distributions would be so scattered in reality. Most likely there are numerous sites where many of these little collected species occur between the scattered current occurrences. To establish which species are truly rare, more effort should be put on inventories. Occurrence of aphyllophorales, especially corticioids and clavarioids are poorly known in all parts of Finland, especially in Åland Islands, Ostrobothnia and Lapland. The archipelago area and Lapland are biogeographically inadequately known parts of Finland because of their somewhat remote location. These areas are also hard to access by researchers. For example, there are 423 species of aphyllophorales found in the Åland Islands [1,5]. Comparing this amount of species to numbers in other biogeographic provinces in southern Finland, it is obvious that dozens of species can still be found there.
Traditionally species inventories have been mainly done in protected areas, but for example in southern Finland only 2.3% of forests are strictly protected [22], and therefore very large areas are not ever inventoried. Also our records are mainly from protected areas.
Accumulation of knowledge of other aphyllophorales than polypores is slow and quite sporadic because there are only few researchers working with aphyllophorales in Finland. Particularly comparing this effort to vast forest area of 22.8 million hectares in Finland [22]. Of course certain portion of aphyllophoroid fungi are rare in reality, for example on the basis of specialization in certain habitat or substrate. The fungal community occupying the smallest dead wood fractions seems to be especially poorly known [23]. The fruiting bodies of many corticioids are so small and inconspicuous that these are hard to find. This is one reason why accumulation of records of some genera is slow. Also taxonomical problems and changes are confusing, and this is not a tempting point of view for amateur mycologists. Tuomo Niemelä, Mari Niemi, Esteri Ohenoja, Keijo Savola, Maarit Similä, Viacheslav Spirin, Unto Söderholm and Terho Taarna. PK is grateful to Nordenskiöld-samfundet i Finland r.f. for financial support.