Collybia cookei

Morphological Features:

Pileus small in size; the diameter of adult specimens rarely reaches 1 cm, usually ranging between 0.5 and 0.8 cm. Initially bell-shaped, it soon becomes convex and finally flattened. It is predominantly white or slightly cream-colored, occasionally retaining an ochraceous tone in the center. The surface is dry and somewhat silky when young, becoming smooth and glabrous with age and rain. The margin is smooth, weakly or not at all striate, and irregularly undulate in old specimens.

Lamellae adnate, white turning cream with age, quite crowded. It is noteworthy that it possesses numerous lamellae for such an extremely small mushroom.

Stipe disproportionately elongated relative to the pileus, cylindrical, and often curved. The surface is furfuraceous, dirty white with flesh-colored tints that intensify upon handling. At the base, it bears a sclerotium yellowish in color with a slight ochraceous tint, but never brown, and certainly not black. It is not uncommon for the sclerotium size to approximate the diameter of the specimen's pileus.

Flesh scant and insignificant, white in color. Once separated from the substrate on which it fruits, no notable odor or taste is detected.

Habitat:

This species should be considered rare or very rare. It has been located in autumn in small groups of several specimens on decaying woody debris of beech wood (Fagus sylvatica), and likewise on pine woody debris. It is also described for this species to fruit on old decaying fungal carpophores, and it can even emerge directly from the soil.

Observations:

Within the genus Collybia and the subgenus of the same name, there are four increasingly interesting species. Collybia cirrhata is the most common of them all, fruiting in large groups on old putrefied Russulas or decomposed woody debris, and lacks a sclerotium. Collybia tuberosa emerges from a dark brownish-black or black sclerotium. Finally, Collybia racemosa is grayish in color and its stipe is adorned with very conspicuous excrescences.