We propose a taxonomic revision of the two closely related white-rot polypore species, Skeletocutis nivea (Jungh.) Jean Keller and S. ochroalba Niemelä (Incrustoporiaceae, Basidiomycota), based on phylogenetic analyses of nuclear ribosomal internal transcribed spacer (ITS) and translation elongation factor EF-1α sequences. We show that prevailing morphological species concepts of S. nivea and S. ochroalba are non-monophyletic and we delineate new species boundaries based on phylogenetic inference. We recognise eleven species within the prevailing species concept of S. nivea (S. calida sp. nov., S. coprosmae comb. nov., S. futilis sp. nov., S. impervia sp. nov., S. ipuletii sp. nov., S. lepida sp. nov., S. nemoralis sp. nov., S. nivea sensu typi, S. semipileata comb. nov., S. unguina sp. nov. and S. yuchengii sp. nov.) and assign new sequenced epitypes for S. nivea and S. semipileata. The traditional concept of S. ochroalba comprises two independent lineages embedded within the S. nivea species complex. The Eurasian conifer-dwelling species S. cummata sp. nov. is recognised as separate from the North American S. ochroalba sensu stricto. Despite comprehensive microscopic examination, the majority of the recognised species are left without stable diagnostic character combinations that would enable species identification based solely on morphology and ecology.

Abstract– A bioenergetics model was used to estimate the food consumption of northern pike (Esox lucius L.) in two lakes in northeastern Finland, and the results compared with those obtained by a method based on stomach contents and gastric evacuation rates. The annual specific food consumption was 7–5 g per one gram pike for one‐ and two‐year‐old pike, and 4–3 g g−1 in age groups 3–6 years old, according to the bioenergetics model. The proportion of ingested food used for growth was 10–30%, and was highest in the youngest age groups. The food consumption rates estimated by the stomach contents method were considerably lower, only about half those produced by the bioenergetics model. The method based on stomach contents tends to underestimate the food consumption. The bioenergetics model was considered more valid for estimating food consumption, but some of the parameter values for northern pike may differ in populations from different latitudes. According to a sensitivity analysis, the food consumption estimate of the bioenergetics model was most sensitive to parameters in the allometric function for respiration.

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Summary Urban green areas are becoming increasingly recognized for their biodiversity potential. However, little is known about how urbanization shapes cryptic species communities, such as those residing in deadwood. In this study, we investigated downed Norway spruce trunks at intermediate stages of decay, in urban and semi‐natural forests in southern Finland. To understand the interconnections between landscape context, deadwood characteristics and wood‐inhabiting fungal communities, we studied structural characteristics, surface epiphyte cover and internal moisture and temperature conditions of the tree trunks, and fungal communities residing in the wood. Our findings showed that urban tree trunks had less epiphyte cover and lower moisture than trunks in semi‐natural forests. Overall, urban forests provide less favourable habitats for a majority of the dominant wood‐inhabiting fungal species and for red‐listed species as a group. Yet, 33% of urban trunks hosted at least one red‐listed species. While these landscape‐scale effects may be driven by local climatic conditions as well as contingencies related to available species pools, our results also highlight the significance of substrate‐scale variability of deadwood in shaping wood‐inhabiting fungal communities. We show that epiphyte cover is a significant driver or indicator of these small‐scale dynamic processes in deadwood.