smallmouth black bass vs smallmouthed bass

smallmouth black bass and smallmouthed bass both are nouns.

Word	Noun	Adjective	Verb	Adverb
smallmouth black bass	Yes	No	No	No
smallmouthed bass	Yes	No	No	No

As nouns, smallmouth black bass and smallmouthed bass are synonyms defined as:

smallmouth black bass and smallmouthed bass: a variety of black bass; the angle of the jaw falls below the eye

Other synonyms of smallmouth black bass include Micropterus dolomieu, smallmouth, smallmouth bass, smallmouthed black bass.

smallmouth black bass (noun)	smallmouthed bass (noun)
a variety of black bass; the angle of the jaw falls below the eye	a variety of black bass; the angle of the jaw falls below the eye