genus Tiarella vs Tiarella

genus Tiarella and Tiarella both are nouns.

Word	Noun	Adjective	Verb	Adverb
genus Tiarella	Yes	No	No	No
Tiarella	Yes	No	No	No

As nouns, genus Tiarella and Tiarella are synonyms defined as:

genus Tiarella and Tiarella: small genus of North American herbs having mostly basal leaves and slender racemes of delicate white flowers

genus Tiarella (noun)	Tiarella (noun)
small genus of North American herbs having mostly basal leaves and slender racemes of delicate white flowers	small genus of North American herbs having mostly basal leaves and slender racemes of delicate white flowers