Hymenogaster luteus

A hypogeous fungus with a white peridium bruising brown upon handling, yellow gleba, and multiform spores.

Outer peridium hyphae filamentous, smooth, hyaline, thin-walled, 3-7 µm wide, densely compacted and interwoven; inner peridium hyphae of globose to angular texture.

Basidia cylindrical to slightly clavate, hyaline, thin-walled, 30-45 µm long and 6-8 µm wide, without basal clamps, mostly 2-spored (literature notes 1- to 4-spored).

Spores multiform: predominantly fusiform, others pyriform, some triangular, smooth-walled, with a smooth to very slightly verruculose perispore, containing a large internal oil or lipid droplet.