(pl. cuticles)
Terms discussed: cellular, cutis, cystoderm, epi-, epiderm, filamentous, hypoderm, ixo-, ixocutis, oedo-, oedotrichodermium, pileipellis, stipitipellis, trichoderm
Topics:
The cuticle itself
describing the cuticle
the prefixes
Various changes in meaning
The cuticle itself
The skin, or outer layer, of the fruiting body is called the cuticle. Pellis and derm are synonyms. These terms can be combined with others to give indications as to where the skin is: for example, pileipellis means the skin of the cap; stipitipellis is the skin of the stalk.
Back to top
describing the cuticle
Similarly, a great many morphemes can be combined to form long terms that give details about the composition of the cutis.
For example, if the hyphae making up the cuticle lie more or less flat on the surface of the mushroom, the term ends in -cutis. If the hyphae stand up straight like the hairs in a crew cut, the term ends in -derm. Nowadays, a trichoderm is a surface composed of erect intertwining hyphae that are of various heights, and whose cells are somewhat elongated. A cystoderm also has erect hyphae, but the cells making them up are round instead of long. A cystoderm is also known as a cellular cuticle, and a filamentous cuticle is a cutis.
Back to top
the prefixes
And then there are prefixes.
The prefix ixo- indicates a slime layer. Oedo- means swollen, or enlarged. Of course epiderm is the outer cuticle, and hypoderm is the inner cuticle.
So an ixocutis is a cuticle consisting of a horizontal layer of hyphae embedded in slime. An oedotrichodermium is a cuticle of uneven erect hyphae, many of them enlarged.
Back to top
Various changes in meaning
In indicating a cuticle of erect hyphae, Snell & Dick (1957) want to require the longer "-trichoderm" and use -derm as a general word for cuticle. Current usage seems to allow the shorter term, but older literature probably uses follows Snell & Dick's usage. He attributes this usage to Lohwag (1941), which I have no info on. Likewise, an alternative definition of -derm is given as "a cuticular structure consisting of an epiderm and a hypoderm and consisting entirely... of universal veil." This definition gets attributed to Gilbert (1947), another publication for which I have no further information.
Back to top
