Helvella costifera

Description

Helvella costifera is a species of fungus in the family Helvellaceae, Pezizales order. Its ascocarp has conspicuous ribs on its undersurface. It is a gray, cuplike cap with an ornately ribbed stem, and the often dramatic extension of the stem's ribs onto the undersurface of the cap.

This species has been found in China, Europe (Spain), and North America (including Mexico), where it is widely distributed.

Mushroom Identification

1. Ecology

   Probably mycorrhizal; growing alone or gregariously, under hardwoods or conifers, often in disturbed ground settings; spring through fall; widely distributed in northern and eastern North America.

2. Cap

   1.5-4.5 cm across; cup-shaped, sometimes becoming more or less flat in age; the margin initially somewhat inrolled; upper surface medium to dark gray-brown or gray, bald, and smooth; undersurface grayish, or sometimes whitish near the stem, finely fuzzy, with forked whitish, blunt, round-edged ribs that extend from the stem, sometimes almost to the margin.

3. Stem

   1-2 cm long; up to 1 cm thick; becoming broader near the cap; deeply ribbed with blunt-edged ribs that extend onto the undersurface of the cap; occasionally developing pockets; white; bald or finely hairy.

4. Microscopic Features

   Spores 14.5-20 x 9.5-12.5 µ; elliptical; smooth; with one central oil droplet. Asci 8-spored. Paraphyses cylindric with subclavate to clavate apices; 4-6 µ wide; hyaline to brownish. Excipular surface elements hyaline to brownish (but when brownish, the pigment resides in the cell walls rather than being intracellular); often arranged in bundles; frequently septate; terminal cells clavate to pyriform.

Synonyms

1. Acetabula costifera (S.Lundell & Nannf.) Benedix (1965)

2. Paxina costifera (Nannf.) Stangel (1963)

Photo sources:

Photo 1 - Author: thinker (CC BY-SA 3.0)