Polyporus arcularius Batsch: Fr.
spring polypore
Polyporaceae

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

Introduction to the Macrofungi

Photograph

© Jim Riley     (Photo ID #73228)


Map

E-Flora BC Static Map

Distribution of Polyporus arcularius
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Species Information

Summary:
Features include a straw to dark brown circular fruitbody with a ciliate margin, large radially elongated hexagonal pores that are cream to buff, central stem, and growth on hardwoods. The radially aligned, hexagonal, relatively large pores, centrally depressed cap, central stem, and thin, tough fruitbodies distinguish Polyporus brumalis (see SIMILAR) and this species from other polypores, (Ginns). The online Species Fungorum, accessed September 3, 2018, gives the current name as Lentinus arcularius (Batsch) Zmitr., International Journal of Medicinal Mushrooms (Redding) 12(1): 88 (2010). MycoBank, accessed the same day, gives that name as a synonym of Polyporus arcularius Batsch: Fr.
Odor:
mushroomy (Lincoff(1)), weak (Breitenbach), none (Miller)
Taste:
mild (Breitenbach)
Microscopic:
spores 7-9 x 2.5-3 microns, cylindric, straight or slightly curved, smooth, inamyloid, colorless; basidia 4-spored, 25-35 x 5-6 microns, clavate, with basal clamp; cystidia none; hyphal system dimitic, generative hyphae in context 2.5-5 microns wide, colorless in KOH, "thin-walled, often branched, with abundant clamps", skeletal hyphae in context 2-11 microns wide, thick-walled, nonseptate, with occasional branching; hyphae of cap surface 1-1.5 microns wide, thin-walled, with clamp connections; hyphae of trama similar, (Gilbertson), spores 7-11 x 2-3 microns, cylindric, smooth, (Arora)
Spore Deposit:
white (Arora)
Notes:
Polyporus arcularius has been found in BC, WA, OR, ID, MB, ON, AL, AZ, CO, CT, DE, FL, GA, IA, IL, IN, KS, KY, LA, MD, MI, MN, MO, MS, MT, NC, NE, NJ, NM, NY, OH, OK, PA, SC, SD, TN, TX, VA, WI, and WV, and it occurs circumglobally, (Gilbertson).
EDIBILITY
too small and tough (Arora)

Habitat and Range

SIMILAR SPECIES
Neofavolus alveolaris usually differs in being laterally stemmed or with stem that is not well formed, and in having larger spores, (Gilbertson). N. alveolaris also has radially elongated pores but the stem is typically lateral or not well formed, the cap is a reddish yellow to pale brick red, and the spores are 11-14 microns long, (Ginns). Polyporus brumalis "also has more or less radially elongated, diamond-shaped pores, but they are much smaller than those of P. arcularius" as well as less radially elongated, and cap is darker, (Gilbertson). P. brumalis has a much darker cap, smaller and less radially elongated pores (angular but less strikingly hexagonal), and smaller spores, (Ginns).
Habitat
annual, single on dead hardwood, also on juniper and Douglas-fir decking, associated with a white rot of dead hardwoods, rarely on conifer wood, (Gilbertson), single or in small groups on dead hardwoods (Arora), on "dead branches and sticks in woodland or on the ground growing from buried wood", (Lincoff(1)), fruiting in summer and fall (Miller)