Russulaceae is a family of fungi in the order Russulales. Its species have typically friable, chalk-like stalks, that break with a distinct crack, like a carrot but with porous flesh (see below). Microscopically, the cells are not all long thin hyphae, which would provide strength and more fibrous appearance when broken. Instead the flesh contains also many large spherical cells ('sphaerocysts'), which give rise to the macroscopic consistency.
However the ITIS Catalogue of life includes also the genera Cystangium, Gymnomyces, Macowanites and Zelleromyces in this family.
Due to the presence of large spherical cells which can be seen under the microscope, an important characteristic to distinguish the Russulaceae from other types of mushrooms is the consistency of the stipe. In Russula and Lactarius, this breaks like the flesh of an apple, whilst in most other families it only breaks into fibres. The pictures compare the broken stipe of a Lactarius vellereus, with that of Suillus variegatus, a member of the Boletaceae.
High diversity of fungi recovered from the roots of mature tanoak (Lithocarpus densiflorus) in northern California.
Sep 01, 2006; Abstract: We collected mature tanoak (Lithocarpus densiflorus (Hook. & Arn.) Rehder) roots from five stands to characterize the...