Caretta caretta vs sea turtle

Caretta caretta and sea turtle both are nouns.

Word	Noun	Adjective	Verb	Adverb
Caretta caretta	Yes	No	No	No
sea turtle	Yes	No	No	No

As nouns, sea turtle is a hypernym of Caretta caretta; that is, sea turtle is a word with a broader meaning than Caretta caretta:

Caretta caretta: very large carnivorous sea turtle; wide-ranging in warm open seas
sea turtle: any of various large turtles with limbs modified into flippers; widely distributed in warm seas

Other hypernyms of Caretta caretta include marine turtle.

Caretta caretta (noun)	sea turtle (noun)
very large carnivorous sea turtle; wide-ranging in warm open seas	any of various large turtles with limbs modified into flippers; widely distributed in warm seas