Pileus: convex, sometimes with a small umbo; 10 – 25mm diameter: rugulose at the centre, fibrillose towards margin, translucently reticulate; dark brown, greyish brown.

Stipe: cylindrical, caespitose, hollow; 30 - 45 × 2 – 2.5 mm; pruinose; grey with white tomentum at base.

Pores : subdecurrent; round to polygonal; white; 2 – 3 per mm; 5 – 9 between stipe and cap margin.

Flesh: white.

Spore print: white.                      

Spores: ellipsoid; 6.5 –9× 5 – 6 µm; smooth, amyloid.

Notes: this species is recognized by its caespitose habit and rugulose, dark brown cap. The closely related F. manipularis, is generally paler or whitish and not clearly caespitose.

Patrick Leonard 2019