sawdust mushroom vs genus Pluteus

sawdust mushroom and genus Pluteus both are nouns.

Word	Noun	Adjective	Verb	Adverb
sawdust mushroom	Yes	No	No	No
genus Pluteus	Yes	No	No	No

sawdust mushroom (noun)	genus Pluteus (noun)
an edible agaric found in piles of hardwood sawdust; the caps are black and coarsely wrinkled	a large genus of fungi belonging to the family Pluteaceae; the shape of the cap resembles a roof; often abundant early in the summer