Noteworthy records of corticioid fungi from Ichnia National Nature Park

. Corticioid fungi constitute a heterogeneous group in terms of origin; they belong to various orders of Agaricomycetes ( Basidiomycota ). According to the available data, ca 280 species of this group have been so far recorded in Ukraine. As compared to other countries of Europe, diversity of corticioid fungi in Ukraine has been insufficiently studied. We made observations and collected corticioid fungi in June–October, 2016 and in March–October, 2017 in forests and woods of Ichnia National Nature Park (Ichnia District, Chernihiv Region, Ukraine). Upon identification of the herbarium specimens collected over the study area, we recorded 90 species of corticioid fungi. This article reports three noteworthy records of corticioid fungi. Two species, Amylocorticium canadense and Tubulicrinis glebulosus , are new records for Ukraine; another one, Aleurodiscus dextrinoideocerussatus , is a rare species both in Ukraine and globally, collected in our country for the second time, and a new record for the Forest-Steppe zone. The specimens were examined in 5% aqueous potassium hydroxide solution, Melzer's reagent and Lactophenol cotton blue. For all the species, we provide descriptions of the examined specimens, along with the original photos, substrate specialization and global distribution details. The collected specimens are deposited in the Mycological Herbarium of the M.G. Kholodny Institute of Botany, National Academy of Sciences of Ukraine ( KW-M ).


Introduction
Corticioid fungi (Basidiomycota) constitute a group of fungi, which is heterogeneous in terms of origin. Fungi of this group form morphologically similar basidiocarps due to convergence. Basidiomata of these fungi are fully resupinate or effuse-reflexed, hymenophore shape varies from smooth to almost poroid, reticulate or irpicoid and long-toothed (Jülich, Stalpers, 1980;Yurchenko, 2006;Zmitrovich, 2008).
Most of corticioid fungi are xylosaprotrophs. Thus, along with polypores they are important components of forest ecosystems, being the major fungal destructors, degrading lignin and cellulose in the nature. Insignificant number of these fungi are pathogens of vascular plants and mycorrhiza-forming fungi (Yurchenko, 2006).
Nowadays, about 1,800 species of corticioid fungi are known in the world (Mueller et al., 2006). In the temperate zone of Europe, 611 species of them are reported (Mueller et al., 2006). Currently, ca. 280 fungi of this group have been recorded in Ukraine (Akulov et al., 2003;Küffer et al., 2004;Usichenko, 2009;Bernicchia, Gorjón, 2010;Ordynets, Yurchenko, 2010;. As compared to other countries of Europe, the corticioid fungi diversity in Ukraine is still insufficiently studied (Akulov et al., 2003;Ordynets, Yurchenko, 2006). Corticioid fungi of the Left-Bank Forest-Steppe have been studied very unevenly. For instance, there are about 100 species of these fungi known for the Kharkiv Forest-Steppe, the best-studied area in this zone (Akulov et al., 2003;Usichenko, 2009). Before we started our surveys, no records of corticioid fungi distribution were reported from Ichnia National Nature Park. Therefore, further examination of these fungi in Ukraine is desirable. and one species, Aleurodiscus dextrinoideocerussatus, which is rare in Ukraine. These species belong to various orders of Agaricomycetes.
The reported taxa are listed in systematic order. The nomenclature is followed by information on morphology, specimens examined, ecological peculiarities and distribution of the species. The original photographs of specific macro-and micromorphological structures are provided for each species.  Fig. 1; a,
Ecological peculiarities: on fallen branches of angiosperms (Bernicchia, Gorjón, 2010) and gymnosperms (Abies Mill., Picea A. Dietr., Pinus L., Tsuga (Endl.) Carrière) (Gilbertson, Lindsey, 1989;Boidin, Gilles, 1990). area, according to the zoning proposed by V. Heluta (1989) in Flora Gribov Ukrainy, belongs to the Left-Bank Forest-Steppe zone. Unique characters of the natural vegetation in Ichnia National Nature Park are determined by its position in the northern part of the Left-Bank Forest-Steppe. In terms of the vegetation cover, the forests prevail, as forest coverage constitutes 83%. The forestlands are of rather limited size, being located relatively evenly all over the park's territory. Among the peculiar features of Ichnia National Nature Park, overlapping of oak, hornbeam and lime forest areas is worth mentioning (Zhyhalenko, 2009). The park's hornbeam forests make up the eastern boundary of the natural range of this species (Zhyhalenko, 2009). Pine forests prevail here, although large areas are also covered with birch and oak forests. Pine forests are located mainly in the northern part of the park, while oak and hornbeam-oak forests occupy the central and southeastern parts, and lime forests are found in the western part of the park. The alder forests occur along the beds of the Udai and Ichenka rivers and their tributaries. Significant areas are covered with pine forest stands (Zhyhalenko, 2009).
According to A. Bernicchia and S. Gorjón (Bernicchia, Gorjón, 2010), it is a rare species all over Europe, recorded from some Mediterranean countries. In Ukraine, this species was reported only once from Luhansk Nature Reserve (Ordynets et al., 2013).
Remarks: both samples from Ukraine, the one found in Ichnia National Nature Park and another in Luhansk Nature Reserve (Ordynets et al., 2013), show no acanthophyses dextrinoid reaction. Moreover, they have subglobose-subovoid basidiospores, unlike the original description, where the spores thereof are of ellipsoid-subovoid shape.