mantis crab vs squilla

mantis crab and squilla both are nouns.

Word	Noun	Adjective	Verb	Adverb
mantis crab	Yes	No	No	No
squilla	Yes	No	No	No

As nouns, squilla is a hyponym of mantis crab; that is, squilla is a word with a more specific, narrower meaning than mantis crab:

mantis crab: tropical marine burrowing crustaceans with large grasping appendages
squilla: a kind of mantis shrimp

Other hyponyms of mantis crab include mantis prawn.

mantis crab (noun)	squilla (noun)
tropical marine burrowing crustaceans with large grasping appendages	a kind of mantis shrimp