• Proposed
  • Under Assessment
  • LCPreliminary Assessed
  • 4Assessed
  • 5Published

Amylocystis lapponica (Romell) Bondartsev & Singer

Go to another Suggested Species...

Scientific name
Amylocystis lapponica
(Romell) Bondartsev & Singer
Common names
tvarožník laponský
późnoporka czerwieniejąca (amylek lapoński)
IUCN Specialist Group
Mushroom, Bracket and Puffball
Assessment status
Preliminary Assessed
Preliminary Category
Proposed by
Anders Dahlberg
Martyn Ainsworth, Anders Dahlberg
Noah Siegel
Anders Dahlberg, Michael Krikorev, Vladimír Kunca, Kamil Kędra, Thomas Læssøe
Comments etc.
Claudia Perini

Assessment Status Notes

European red-list assessment; NT close to VU (A2c+3c+4c), population decline approaching 30 % during the last 30 years and the decline is expected to continue at the same speed in the next 30 years. The past, ongoing and expected decline may exceed 30%, if so VU. Evaluation period (= 3 generations) is considered to be 30 years for A. lapponica.


Amylocystis lapponica is a widespread circumboreal wood-decaying fungus in coniferous forest ecosystem in Asia Europe and North America. It is growing in old-growth humid forest growing in coarse logs of predominantely Norway spruce ADD TREE SPECIES IN AMERICA. In Europe, the species is used as an indicator species for old-growth conditions and nationally red-listed in Fennoscandia as its habitats disappear due to clearcutting of oldgrowth forest. In North America it is common ........ ADD NOAH

Amylocystis lapponica is nationally assessed as declining in northern Europe Europe whereas in North America there is no evidence of decline. It can be locally abundant where suitable habitat exists. Therefore, it is assessed as Least Concern (LC).

Taxonomic notes

Why suggested for a Global Red List Assessment?

The habitat where this wood-inhabiting species occurs is predominantly old-growth coniferous boreal forest with an abundant supply of coarse woody debris (CWD) of Norway spruce. Outside protected areas, such CWD is continuously disappearing due to clear cutting. The species does not seem to be able to re-colonise in managed forest, probably due to lack of appropriate types of coarse dead wood, unfavourable habitat conditions, its relative rarity and hence reduced fitness. Red-listed in seven European countries.

Preliminary global red-list assessment; NT close to VU (A2c+3c+4c), population decline approaching 30 % during the last 30 years and the decline is expected to continue at the same speed in the next 30 years. The past, ongoing and expected decline may exceed 30%, if so VU. Evaluation period (= 3 generations) is considered to be 30 years for A. lapponica as recommended for wood-inhabiting species on Norway spruce by Dahlberg & Mueller, 2011. It has a European (and global) population that exceeds 20 000 mature individuals. Cause of decline: Clear cutting and transformation of its main habitat, old growth forests of Norway spruce with large amounts of CWD, into managed forests with shorter rotation times and significantly reduced volumes of appropriate types of dead wood. The population decline is estimated/inferred from habitat decline. Only a small percentage of the global distribution of appropriate coniferous forest is protected. These fragments, free from forestry management, offer potential refugia for A. lapponica. It is not, or only sparsely, recorded in managed forests.

In North America it occurs across the northern latitudes, and south in the mountains. It is currently known from ~300 locations, but is considered under reported, and a large amount of suitable habitat have not been surveyed for this species. In Northeast NA it occurs both on native spruce forests, and in some Norway spruce plantations. There are scattered reports (on Mycoportal) from Quebec and Ontario; the Canadian National Mycological Herbarium (DAOM) has not been digitized, and accessible data is lacking. It occurs in the Rocky Mountains, from Arizona and New Mexico, USA in the south, north into British Columbia and Alberta, Canada. It also is fairly common on the Pacific Coast, from Humboldt County, California into south-central Alaska (roughly following the range of Sitka Spruce). Records in the Sierra Nevada and Cascade ranges (in California, Oregon and Washington) may represent a distinct species, as these fruit on Abies magnifica and A. concolor, often in the spring following snowmelt. 

Present lack of knowledge; How frequent and widely distributed is it in north America and Asia? It appear to be reported from plantations in NAm.

Geographic range

Amylocystis lapponica has a circumboral distribution; Asia, Europe and North America. Outside the boreal zone, appropriate habitat is sparse. It is reported from a few central European countries and the Changbaishan Nature Reserve in north-eastern China.

Population and Trends

In Europe, A. lapponica occurs almost exclusively in boreal old-growth forests with Picea abies. The majority of known European localities are situated in Sweden and Finland. It is likely that the population is larger in Russia. The number of known localities in Europe was estimated to 1000 in 2015 (Fraiture & Otto 2015). In Europe, the population of A. lapponica is declining due to clearcutting of old-growth forests and as seems have poor ability to re-colonise in managed forest. In Finland and Sweden, the populations are estimated to have declined by >15% since 1985. In Norway it is assessed to have declined by >30%  since 1985. It has not been assessed for national red-listing in Russia, but is included in several regional Russian Red Lists, e.g. the Sverdlovsk Region (Shiryaev et al. 2010) where it is assessed as VU.The status in the boreal parts of Asia is poorly know. In North America, it is widespread and regarded as “particularly common on spruce logs” and is recorded within 20 states/provinces (Gilbertson & Ryvarden 1986).  ADD NOAH sometimes

Population Trend: Deteriorating

Habitat and Ecology

Amylocystis borealis is a wood-decomposing fungus forming brown rot. It grows almost exclusively in coarse fallen logs of Norway spruce (Picea abies), larch (Larix) and rarely on pine (Pinus) in un-evenaged virgin old growth forests and forests historically subjected to selective cutting with a long continuity of logs. It occurs in forests with high humidity, typically spruce swamp forest, herb-rich mesic-moist spruce forest and mountain spruce forests. It is used as an indicator species for old-growth forests and woodland key habitats. The sporocarp is annual while the mycelium is long-lived and potentially present in logs for many decades. It does not seem to be present in managed forests in Europe.

The mycelia of A. lapponica seem largely to be located in the inner parts the log, and it has been speculated that it colonize cracks may be a convenient way to reach the surface for fruit body
formation. Cracks may also serve as an early entrance for colonization, possibly already when the tree stands as a snag.

The cause of dead wood characteristics (e.g. cause of death, type of breakage, and whether the dead tree stood as a snag
for a long time or not) may play a more important role for
A. lapponica colonization

Boreal Forest


The main threat to and cause of A. lapponica to decline is clear cutting and transforming of old growth forests with high amount of CWD into managed forests with shorter rotation times and few of coarse logs. A large portion of the appropriate habitate of A. lapponica have been cut during the last half centuary due to forestry in northern Europe and the major part of remaining appropriate forests is expected to disappear within the next 50 years. Not or only sparsely recorded in managed forests. The FSC recommends certain conservation considerations for forest management, however implementation of these is only expected to slightly diminish the expected continued large decline in the population of A. lapponica.

The population is inferred to have declined from the reduction of appropriate habitat decline. Only a small percentage of the global distribution of appropriate coniferous forests is protected and not subjected to modern forest management.

Logging & wood harvesting

Conservation Actions

Setting aside forest reserves occupied by A. lapponica in which there is a continous formation of coarse dead wood (logs) of Norway spruce. If site protection is not possible, A. lapponica may survive clearcutting if large areas (>0.5 ha) with dead wood are set aside for nature conservation within the area to be cut. Similarly, restricted selected cutting management may be the next best option if sufficent areas with dead wood are set aside for nature conservation.

Site/area protectionSite/area management

Research needed

There are some apparent ecological differences between European and N. American populations. In N. America it occurs in Picea plantations and whereas it seems to fruit late in the year in Europe, it is a spring fruiter (soon after snowmelt) in some areas of N. America. Insufficient DNA barcode (ITS) sequences in GenBank and UNITE to resolve whether there is taxonomically significant divergence of European and N. American populations.

Use and Trade


Dahlberg A & Croneborg H. 2003. 33 threatened fungi in Europe. Complementary and revised information on candidates for listing in Appendix I of the Bern Convention T-PVS (2001) 34 rev 2.
Dahlberg A & Mueller G. 2011. Applying IUCN red-listing criteria for assessing and reporting on the conservation status of fungal species. Fungal Ecology 4: 1-16
Dai Y. 2003. Rare and threathened polypores in the ecosystem of Changbaishan Nature Reserve of northeastern China [Article in Chinese]. Ying Yong Sheng Tai Xue Bao (The Journal of Applied Ecology). 14(6):1015-8
Gilbertson RL. & Ryvarden L. 1986. North American Polypores vol1. Fungiflora, Oslo.
Nitare J. 2010. Signalarter. 4th edn. Indikatorer på skyddsvärd skog. (Indicator Species. Indicators of forests of conservation interest. Flora of cryptogams. In Swedish with an English summary). Skogsstyrelsen (Swedish Forest Agencey). Jönköping, Sweden
Otto P, 2011. Ecology and chorology of 51 selected fungal species. Draft, Leipzig (unpublished)
Ryvarden L & Melo I. 2014. Poroid fungi of Europe. Synopsis Fungorum 31. Fungiflora, Oslo
Shiryaev AG., Kotiranta H., Mukhin VA., Stavishenko IV. & Ushakova NV. 2010. Aphyllophoroid fungi of Sverdlovsk Region, Russia. Goshchitskiy, Ekaterinburg.
Tortic M. 1998. An attempt to a list of indicator fungi (Aphyllophorales) for old forests of beech and fir in former Yugoslavia. Folia Cryptog. Estonica. Fasc. 33: 139-146

Known distribution - countries

Regional Population and Trends

Country Trend Redlisted