mulberry vs Morus rubra

mulberry and Morus rubra both are nouns.

Word	Noun	Adjective	Verb	Adverb
mulberry	Yes	No	No	No
Morus rubra	Yes	No	No	No

As nouns, Morus rubra is a hyponym of mulberry; that is, Morus rubra is a word with a more specific, narrower meaning than mulberry:

mulberry: any of several trees of the genus Morus having edible fruit that resembles the blackberry
Morus rubra: North American mulberry having dark purple edible fruit

Other hyponyms of mulberry include Morus alba, white mulberry, black mulberry, Morus nigra, red mulberry.

mulberry (noun)	Morus rubra (noun)
sweet usually dark purple blackberry-like fruit of any of several mulberry trees of the genus Morus	North American mulberry having dark purple edible fruit
any of several trees of the genus Morus having edible fruit that resembles the blackberry