ribbed toad vs toad

ribbed toad and toad both are nouns.

Word	Noun	Adjective	Verb	Adverb
ribbed toad	Yes	No	No	No
toad	Yes	No	No	No

As nouns, toad is a hypernym of ribbed toad; that is, toad is a word with a broader meaning than ribbed toad:

ribbed toad: western North American frog with a taillike copulatory organ
toad: any of various tailless stout-bodied amphibians with long hind limbs for leaping; semiaquatic and terrestrial species

Other hypernyms of ribbed toad include anuran, batrachian, frog, salientian, toad frog.

ribbed toad (noun)	toad (noun)
western North American frog with a taillike copulatory organ	any of various tailless stout-bodied amphibians with long hind limbs for leaping; semiaquatic and terrestrial species