Galerina sulciceps

A species of Galerina

The cap is initially egg-shaped in young specimens, but changes shape as it matures, becoming convex and later more or less flat with a central depression. At the center of the cap is a roughly spherical umbo – a nipple-like protrusion. The cap is hygrophanous, meaning it changes color depending on its state of hydration: the color is tawny in moist specimens, changing to ochre with dark brown edges when dried. The cap diameter is typically 1.5 to 4 cm (0.6 to 1.6 in), with a surface that is smooth, and almost gelatinous in consistency. The edge of the cap is thin and wavy, and is often split open. The gills are broadly adnate (broadly attached to the stalk slightly above the bottom of the gill, with most of the gill fused to the stem) to slightly decurrent (running down the length of the stem). Interspersed between the gills are shorter gills, called lamellulae, that start from the cap but do not reach the stem. The gills are broad (up to 4 mm) and thick at the base (1 mm), and when mature can develop veins that run between the gills on the undersurface of the cap. The stem is 0.4 to 2.5 cm (0.2 to 1.0 in) long, 0.15 to 0.3 cm (0.06 to 0.12 in) thick, and usually attached centrally to the underside of the cap, although it may sometimes be slightly off-center. Stems are solid, cylindrical, and may be pruinose (dusted with a very fine layer of powder). Berkeley's original description noted a resemblance to a small Marasmius peronatus, a mushroom today known as Gymnopus peronatus.