In northern California, there are three genera in which the pileus and the stipe are uniformly grayish or gray-brown and the pileus is often hygrophanous and translucent-striate: Fayodia, Myxomphalia, and Tephrocybe.

Fayodia: pileus dry; pileus and stipe are uniformly colored grayish or brownish, often somewhat hygrophanous and slightly to distinctly translucent-striate; the gills are white and either emarginate or decurrent; odor typically not fishy or farinaceous. The genus is characterized by its cyanophilous warty or spiny spores. Habitat: on woody debris, soil, leaf litter, rarely in burned over areas.

Myxomphalia: pileus oily, depressed or umbilicate over the center; pileus dark brown to dark gray-brown, translucent-striate, and strongly hygrophanous; gills are white or sordid gray; odor not fishy or farinaceous. Habitat: in burned over areas. It is recognized by its slightly warty to nearly smooth, amyloid spores.

Tephrocybe: Collybia-like species with dull grayish, grayish brown, or blackish colors. Pileus moist but not lubricous and translucent-striate. Often with strong, fishy or farinaceous odors. Habitat: in grassy areas, forested areas, or in burned areas. It is characterized by its siderophilous basidia.