Amylocystis lapponica (Romell) Singer
no common name

Species account author: Ian Gibson.
Extracted from Matchmaker: Mushrooms of the Pacific Northwest.

Introduction to the Macrofungi


© Michael Beug     (Photo ID #65515)


E-Flora BC Static Map

Distribution of Amylocystis lapponica
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Species Information

{See also Amylocystis lapponica, Leptoporus mollis, Postia fragilis Table.} Features include a light buff bracket-like or shelf-like fruitbody with a tomentose to bristly cap that becomes dark reddish brown on bruising or drying, white angular pores that become dark reddish brown when old, growth on conifer wood, and microscopic characters including amyloid hyphae and cystidia. The description is derived from Gilbertson(1).
slightly bitter, anise-like
spores 8-11 x 2.5-3.5 microns, cylindric, smooth, colorless, inamyloid; basidia 4-spored, 20-25 x 7-8 microns, with basal clamp connection; cystidia abundant, 30-45 x 5-9 microns, projecting to 15 microns, fusiform, mostly thick-walled, moderately to strongly amyloid, some incrusted at apex; hyphal system monomitic, generative hyphae 4-10 microns wide, with abundant clamp connections, mostly thick-walled with a narrow and sinuous lumen, colorless in KOH, weakly to strongly amyloid, tramal hyphae similar, 3-4.5 microns wide, amyloid
Amylocystis lapponica has been found in BC, WA, OR, ID, AB, MB, ON, PQ, AK, AZ, CA, CO, MI, MN, MT, NH, NY, UT, VT, and WY, (Gilbertson).

Habitat and Range

The characters of this genus are similar to those of Postia with the exception of the amyloid hyphae and cystidia. Postia fragilis (=Oligoporus fragilis) fruitbodies resemble less robust specimens of A. lapponica and also show the reddish-brown color change on bruising, but P. fragilis lacks the capitately incrusted amyloid cystidia of A. lapponica, spore size is smaller, and pore size is slightly smaller, (Gilbertson). A. lapponica has cylindric spores 8-11 x 2.5-3.5 microns, clamp connections, and amyloid metuloids, Leptoporus mollis has allantoid spores 5-6 x 1.5-2 microns, no clamp connections, and no cystidia, and Postia fragilis has allantoid spores 4-5 x 1-1.5 microns, clamp connections, and no cystidia, (Ginns(25)). Sarcoporia polyspora also stains reddish brown, has elliptic to cylindric spores measuring 5-7 x 2.5-4.0 microns, has clamp connections, and lacks cystidia.
annual; on conifers, forming a brown cubical rot, and functioning as a decomposer of fallen trees, particularly common on spruce logs and its fruiting bodies develop near melting snow early in spring


Synonyms and Alternate Names:
Lycoperdon gemmatum Batsch
Polyporus lapponicus Romell