Etym.: The name refers to the fimbriate nature of the mouth.
[description of typical variety only]
Spore-sac up to 15 mm diam, globose, generally well adhered to the stem. Exoperidium distinctly hyphal, with the hyphae agglutinated with sand grains, sometimes rather loosely, forming a more or less persistent to deciduous basal band. Endoperidium sordid cinereous white, sometimes with slightly metallic glister, or ochraceous-greyish, generally smooth but often with the scars of the sand grains quite visible, tough, when old and weathered it may become parchment-like. Mouth typically fibrillose-fimbriate, sometimes slightly mammose, and may become denticulate with age, in many specimens exhibiting a typical granulose or punctate aspect. Socket most times inconspicuous, shallow, with the membrane subentire or lacerate. Gleba ochraceous to light brown or ferrugineous. Stem up to 50 x 3 mm, straight or slightly tapering downwards, smooth to squamulose, brown to reddish brown, generally dirty brown, lighter when old, squamules normally appressed but sometimes erect, appearing squarrulose, sometimes with 2-3 longitudinal furrows.
Exoperidium formed by interwoven brown hyphae. Spores densely and conspicuously verrucose under L.M., globose to subglobose, light brown, 4.3-5.7-(6) x (3.6)-4.6-5.1 µm. Under SEM the ornamentation appears as thick, uneven, appressed verrucae, some tending to become deformed in Y-shaped crests, but generally little anastomosed. Capillitium hyaline to slightly yellowish, branched and scantily septate; threads 3.5-6-(7.7) µm diam, thick-walled, lumen visible to lacunar or solid, somewhat enlarged at the slightly coloured, disjointable septa.
Habitat: in sandy soil of steppose sites in relatively warm regions.
Distribution: it is a typically European species, and probably the most common one, and mayhave been introduced in other regions.