bracket fungus vs shelf fungus

bracket fungus and shelf fungus both are nouns.

Word	Noun	Adjective	Verb	Adverb
bracket fungus	Yes	No	No	No
shelf fungus	Yes	No	No	No

As nouns, bracket fungus and shelf fungus are synonyms defined as:

bracket fungus and shelf fungus: a woody fungus that forms shelflike sporophores on tree trunks and wood structures

bracket fungus (noun)	shelf fungus (noun)
a woody fungus that forms shelflike sporophores on tree trunks and wood structures	a woody fungus that forms shelflike sporophores on tree trunks and wood structures