Postia fragilis (Fr.) Julich
No common name
Uncertain
Species account author: Ian Gibson.
Extracted from Matchmaker: Mushrooms of the Pacific Northwest.
Introduction to the Macrofungi
No common name
Uncertain
Species account author: Ian Gibson.
Extracted from Matchmaker: Mushrooms of the Pacific Northwest.
Introduction to the Macrofungi
Photograph
Species Information
Summary:
{See also Amylocystis lapponica, Leptoporus mollis, Postia fragilis Table.} Features of Postia fragilis are the bracket-like or shelf-like, whitish to buff fruitbodies that turn reddish brown on bruising or drying, and its microscopic characters. The current name in the online Species Fungorum, accessed April 20, 2020, is Fuscopostia fragilis, but the current name in Mycobank, accessed the same day, is Postia fragilis.
Odor:
strong (Phillips), insignificant (Breitenbach)
Taste:
mild (Breitenbach)
Microscopic:
spores 4-5 x 1-1.5 microns, cylindric, mostly curved, smooth, inamyloid, colorless; basidia 4-spored, 13-20 x 4.5-5.5 microns, clavate; cystidia none; hyphae monomitic, hyphae of context 3-7 microns wide, colorless in KOH, thin-walled or thick-walled, occasionally branched, with clamp connections, hyphae of trama 2.5-4 microns wide, colorless, thin-walled or thick-walled, often branched, with clamp connections, (Gilbertson), 4-5 x 1-2 microns, cylindric to sausage-shaped, smooth, (Arora), spores 4.5-6 x 1.5-2 microns, cylindric, somewhat allantoid, smooth, colorless, with droplets, (Breitenbach), spores 4-5 x 1.0-1.5 microns, allantoid, hyphae 3-7 microns wide, walls thin to thick, hyphae on cap surface "mostly thin-walled in agglutinated pale yellow to pale brown strands", (Ginns(28))
Spore Deposit:
whitish (Arora)
Notes:
Postia fragilis is found in BC, WA, OR, ID, AB, NB, NS, ON, PQ, AK, AZ, CA, CO, FL, MA, MD, ME, MI, MN, MT, NC, NH, NJ, NM, NY, PA, TN, UT, VA, WI, and WY, (Gilbertson), and Europe, Asia, and Australia, (Breitenbach).
EDIBILITY
unknown (Arora)
Habitat and Range
SIMILAR SPECIES
Amylocystis lapponica fruitbodies "resemble robust specimens of O. fragilis and also show the reddish-brown color change on bruising. The capitately incrusted amyloid cystidia of A. lapponica make it distinctive microscopically" - spore size is larger and pore size is slightly larger for A. lapponica, (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 - it has elliptic to cylindric spores 5-7 x 2.5-4.0 microns, has clamp connections, and lacks cystidia. Postia lateritia, rarely reported, has larger pores (3-4 per mm), soft context, slightly larger pores measuring 4.5-6.3 x 1.0-1.8 microns, thick-walled cap hyphae (thin-walled in P. fragilis), and scattered gloeoplerous hyphae (Ginns(28)). See also SIMILAR section of Postia leucomallella.Habitat
annual, single, on dead conifers, rarely on Populus; associated with brown cubical rot of dead conifer logs and slash, (Gilbertson), single "or in groups or fused clusters on rotting conifers", (Arora), summer to fall (Buczacki)
Status Information
Synonyms
Synonyms and Alternate Names:
Peniophora affinis Burt
Peniophora laevis (Fr.) Burt in Peck sensu Burt 1902