Gills: adnate, subfuscous or dark dirt-brown.
Flesh: dirty buff and with no distinct smell.
Spore-print: pale snuff-brown with purplish flush.
Spores: long, ovoid, yellowish-grey brown under the microscope with a distinct germ-pore and 10-12 × 7 µm in size.
Marginal cystidia: balloon-shaped, obtuse or somewhat bottle-shaped and hyaline.
Facial cystidia: sparse, similar to the marginal cystidia, voluminous.
General Information: This is a very distinct fungus found amongst stems of Marram grass in sand-dune systems. At first sight it appears as if it is growing in the bare sand, but by careful excavation it usually is found attached to pieces of Marram grass, indeed the hyphae enter the roots of the grass, but apparently do not kill them.
This fungus was first described in the genus Psilocybe (see [p. 114]) because of its brownish purple spore-print, but the cap-surface is composed of rounded cells and so is related to all the other species of Psathyrella.
Psathyrella flexispora Wallace & P. D. Orton grows in similar habitats amongst Ammophila and other seashore grasses. It is easily recognised by the chocolate, umber or date-brown cap and the peculiar shaped spores, which look as if they have been slightly twisted during their development.