Cerioporus leptocephalus

Description
Mushroom Identification
Look-Alikes
Medicinal Properties
History
Synonyms

Description

Cerioporus leptocephalus is an inedible species of mushroom in the genus Cerioporus. It usually grows on the branches of broad-leaved trees. Formerly placed in the genus Polyporus (Polyporus leptocephalus), this species was moved into Cerioporus in 2016.

The cap is convex when young and soon flattens out into a mostly irregular shape. It is red-brown when young, yellowish-gray when old, and usually about 2–5 cm in diameter. The pores are white, turning slightly brown when bruised, and the spores are white. The stem is light yellowish brown often with a black base.

Common names: Blackfoot Polypore, Löwengelber Stielporling (German), Polypore variable (French), Mustasukkakääpä (Finnish).

Mushroom Identification

Pileus

Fruiting body annual, stipitate, cap 2.0-5.0 cm broad, convex, becoming convex-umbillicate to funnel-form in profile, round to kidney-shaped in outline; margin incurved, decurved to nearly plane in age, often wavy, not striate; upper surface glabrous, cream to tan-brown; context up to 5 mm thick, pliant, tough, colored like the cap surface, unchanging when injured, cork-like when dried; odor slightly aromatic, sharp; taste, mild to slightly astringent.
Hymenophore

Pores 5-6 per mm, rounded, angular to occasionally elongated into slits, descending the stipe a short distance, cream-buff when young, tan-brown at maturity, unchanging when bruised; Tubes up 2.0 mm in length, not separable from the cap.
Stipe

0.5-6.0 cm long, 4.0-8.0 mm thick, rarely absent, solid, tapering to a narrowed base, variable in the attachment: central, eccentric or lateral; surface cream-buff at apex, blackish-brown below, irregularly roughened, sometimes wrinkled or checked like tree bark, occasionally peeling away revealing a brownish under-layer; context tough, pliant, colored like that of the cap, unchanging.
Spores

Spores 7.5-9.0 x 2.0-3.5 µm, oblong-ellipsoid, smooth, thin-walled, inamyloid; spores white in deposit.
Habitat

Solitary or in small groups, primarily on hardwood branches or logs; fruiting from early to late winter.

Look-Alikes

Polyporus badius

A shiny red-brown to the purple-black cap which can grow up to 20 cm across, and the dark brown.
Polyporus melanopus

Tends to grow from buried wood, has a reddish-brown to the dark-brown cap, and a dark-colored, centrally attached stipe.
Polyporus ciliatus

Similar but does not have a black stem base.
Polyporus brumalis

Similar but has larger pores and does not have a black stem base.
Polyporus durus

Has a red-brown cap and generally has larger caps.

Medicinal Properties

Antitumor effects. Polysaccharides extracted from the mycelial culture of P. leptocephalus and administered intraperitoneally into white mice at a dosage of 300 mg/kg inhibited the growth of both Sarcoma 180 and Ehrlich solid cancers by 60% (Ohtsuka et al., 1973).

History

The basionym of this species dates from 1778, when Dutch naturalist Nicolaus Joseph von Jacquin (1727 - 1817) described this polypore and gave it the binomial scientific name Boletus leptocephalus. It was Swedish mycologist Elias Magus Fries who, in 1821, transferred this species to the genus Polyporus, thereby establishing its currently accepted scientific name.

Polyporus, the genus name, comes from poly, meaning many, and poros, meaning passage - in this instance, the tubular holes known as pores on the fertile (spore-producing) underside of the cap and within which spores develop.

The specific epithet leptocephalus comes from the Greek adjective lept- meaning slim or slender, and -kephale meaning a head - hence by implication this polypore has a slim head or cap.