mojarra vs silver jenny

mojarra and silver jenny both are nouns.

Word	Noun	Adjective	Verb	Adverb
mojarra	Yes	No	No	No
silver jenny	Yes	No	No	No

As nouns, silver jenny is a hyponym of mojarra; that is, silver jenny is a word with a more specific, narrower meaning than mojarra:

mojarra: small silvery schooling fishes with protrusible mouths found in warm coastal waters
silver jenny: silvery mojarra found along sandy shores of the western Atlantic

Other hyponyms of mojarra include Gerres cinereus, yellowfin mojarra, Eucinostomus gula.

mojarra (noun)	silver jenny (noun)
small silvery schooling fishes with protrusible mouths found in warm coastal waters	silvery mojarra found along sandy shores of the western Atlantic