long-stalked gray cup

The apothecium of Helvella macropus is a stalked, cup-like structure that typically forms a regular, saucer-shaped head measuring 1.5–3 cm across. Its spore-bearing surface, or hymenium, varies from yellowish to greyish-brown, and the outer cup (receptacle) is the same colour and densely covered in fine hairs (villose). The supporting stipe is slender and cylindrical, ranging from 2.5 to 12 cm in height and 3–5 mm in width, with a pubescent (hairy) surface that emphasises its hollow interior. Beneath the hymenium lies the medullary excipulum, a loosely interwoven network of brownish hyphae about 4–6 μm wide, some inflated to 10–20 μm and constricted at their septa. Outside this is the ectal excipulum, where the innermost hyphae also form a textura intricata of cells 10–30 μm across. Toward the surface, these cells reorganise into fascicled rows of cylindrical hyphae 20–35 μm long by 10–15 μm wide, and some extend into tufts of hyphoid hairs up to 200 μm in length. The spore-bearing ascus are pleurorhynchous—originating from a hooked basal cell—and measure 240–300 × 13–16 μm, each enclosing eight ellipsoid-fusoid ascospores. These spores are 19.5–25.8 μm long by 9–12.0 μm wide and contain one large plus two to three medium-sized oil droplets (guttules). …

This species has a wide distribution in the Northern Hemisphere, having been recorded throughout North America, as well as in Central America, Europe, China, and Japan. It can be found on the ground or on rotting wood along with moss.