Assessment Notes

Justification

Resinoporia piceata is a wood-decaying fungus with resupinate annual to perennial fruitbodies. Most records of Resinoporia piceata are from old-growth forests, where it inhabits large lying trunks of conifer trees, mostly Picea spp. The species is declining due to clear-cut forestry and fragmentation of older forests with dominance of conifers, especially spruce. It is an Eurasian species, known only from 14 countries worldwide (many of countries with only one or two localities), with very rare occurrence throughout its distribution range.

Decline in area and quality of old-growth and old forests with dominance or partial representation of conifers is the main threat. Many of the known sites of the species are strictly protected in Europe but some needs to be declared non-intervention areas.

This recently described species is delimited from a number of morphologically similar species primarily on DNA sequence data. Challenges in field identification probably results in under-reporting of this species making it difficult to estimate the number of mature individuals and its distribution. 

This uncertainty results in assessing this species as Data Deficient.

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Taxonomic notes

The species was previously considered conspecific with Amyloporia (Antrodia) sitchensis. The distinction of the species from morphologically similar species relies mainly on the DNA characters and distribution ranges (Spirin et al. 2015). Recently the species was moved to genus Resinoporia (Audet 2017).

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Geographic range

Resinoporia piceata occurs in Eurasia, in boreal and temperate zone, but has rarely been reported (Spirin et al. 2015, Holec et al. 2015).

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Population and Trends

Some localities of Resinoporia piceata belong among the most valuable old-growth forests in Central Europe. This applies to two localities in Slovakia (Kunca unpublished), one in Czechia (Holec et al. 2015) and two localities in Poland (Karasiński and Wołkowycki 2015). There are 8 confirmed records in Finland (Kunttu et al. 2016) and 35 records from 15 to 20 localities from old-growth forests in Estonia (Runnel and Lõhmus 2017, Runnel pers. comm.). In Norway, 11 localities of the species are known (Rolstad and Storaunet 2015) and in Sweden ca. 7 localities (Shah and Coulson 2019). Complete data for Russia are missing but based on the web literature review we can assess there are at least 5 localities of the species. In regions where the species occurs, it has been rarely reported (Spirin et al. 2015, Ezhov et al. 2017). In Japan probably only one locality is known (Núñez and Ryvarden 1999). In China the species occurs “occasionally” on four hosts and we can estimate that ca. 10 localities are known (Dai 2012). Altogether ca. 60-65 localities of the species are known. Localities of the species in central Europe are fairly fragmented.

The primary habitat of Resinopoia piceata - old-growth forests with Picea spp. or Abies spp., - is decreasing, especially in areas in Europe. Primary forests in Europe cover only 0.7% of forest area (Sabatini et al. 2018), and it is expected the decrease will continue. Conifers suffer in changing climate conditions and the attacked or damaged individuals and stands are cut and wood is taken from forests. Large trunks, as crucial substrate, are being decayed at many localities and no big trees occur in some areas.

Population Trend: decreasing

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Habitat and Ecology

Resinoporia piceata is a wood-decaying fungus inhabiting large lying trunks of conifer trees in later stages of decay, particularly in natural and seminatural forests (Niemelä et al. 1992, Kunttu et al. 2014, Holec et al. 2015, Kunttu et al. 2016). The species is sometimes also reported from stumps and dead standing trees. It grows almost exclusively on Picea (Spirin et al. 2015), but sporadically was collected from Abies alba (Vampola and Pouzar 1992, Vlasák 2007, unpublished from Slovakia) and Pinus sylvestris (Niemelä et al. 1992); once from Populus (Karasiński and Wołkowycki, 2015). In China, it is reported from Larix and Cunninghamia, as well as Picea and Pinus (Dai 2012). It is proposed to be an old-forest indicator (Runnel and Lõhmus 2017, Lõhmus et al. 2018). Most known localities of R. piceata are old-growth forests (Spirin et al. 2015).

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Threats

The habitat of R. piceata, old-growth forests with conifers, is declining due to clearcutting, intensive forest practices (e.g. processing spruce trees attacked by bark beetle) and removing logs of Picea sp. after wind storms or pest outbreaks (salvage cuttings), even from protected areas. In the well-known Bialowieza forest, the threat results from cutting in the area, especially spruce trees (Boczoń et al. 2018). Another threat is also the decrease of Picea abies population due to changing climate conditions – global warming (Boczoń et al. 2018). A similar, long-term problem is well-known with regeneration and survival of Abies alba in Europe (Elling et al. 2009). Based on presented data, large logs of fir are another important substrate for R. piceata.

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Conservation Actions

Known old-growth forest localities with occurrence of R. piceata should be protected without any forest management practices. R. piceata needs coarse woody conifer debris, especially logs, in different stages of decay. Research is needed to better understand different aspects of the species’ ecology to facilitate development of potential conservation plans and more appropriate management.

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Use and Trade

Fruitbodies of the fungus are not known to be used or collected.

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Source and Citation

Kunca, V. 2019. Resinoporia piceata. The IUCN Red List of Threatened Species 2019: e.T148050068A148050253. https://dx.doi.org/10.2305/IUCN.UK.2019-3.RLTS.T148050068A148050253.en .Accessed on 1 February 2023

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• Country occurrence