The pileipellis is the uppermost layer of

hyphae A hypha (; ) is a long, branching, filamentous structure of a fungus, oomycete, or actinobacterium. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium. Structure A hypha consists of one or ...

in the pileus of a

fungal A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from th ...

fruit body In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering. Fruits are the means by which flowering plants (also known as angiosperms) disseminate their seeds. Edible fruits in particu ...

. It covers the trama, the fleshy tissue of the fruit body. The pileipellis is more or less synonymous with the cuticle, but the cuticle generally describes this layer as a macroscopic feature, while pileipellis refers to this structure as a microscopic layer. Pileipellis type is an important character in the identification of fungi. Pileipellis types include the cutis, trichoderm, epithelium, and hymeniderm types.

Types

Cutis

A cutis is a type of pileipellis characterized by hyphae that are repent, that is, that run parallel to the pileus surface. In an ixocutis, the hyphae are gelatinous.

Trichoderm

In a trichoderm, the outermost hyphae emerge roughly parallel, like hairs, perpendicular to the cap surface. The prefix "tricho-" comes from a Greek word for "hair". In an ixotrichodermium, the outermost hyphae are gelatinous.

Epithelium

An epithelium is a pileipellis consisting of rounded cells in multiple layers, often connected in chains, and sometimes breaking off.Glossary of ''Coprinus'' site of Kees Uljé
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Hymeniderm

Also called hymeniform, or palisade at times. When viewed from above, a hymeniderm or "cellular cuticle" appears to be paved with roughly circular polygonal elements (similar to the fertile cells of the actual hymenium on the gills). The elements may be globular cells or may be the tips of hyphae extending deeper into the surface.Régis Courtecuisse : "Mushrooms of Britain & Europe" (Harper Collins 1999). - see Glossary.Meinhard Moser, translated by Simon Plant: ''Keys to Agarics and Boleti'' (Roger Phillips 1983) - see Technical Glossary.

External links

IMA Mycological Glossary: Pileipellis

References

{{reflist Fungal morphology and anatomy