skeleton shrimp vs amphipod

skeleton shrimp and amphipod both are nouns.

Word	Noun	Adjective	Verb	Adverb
skeleton shrimp	Yes	No	No	No
amphipod	Yes	No	No	No

As nouns, amphipod is a hypernym of skeleton shrimp; that is, amphipod is a word with a broader meaning than skeleton shrimp:

skeleton shrimp: small amphipod crustacean having a grotesque form suggestive of the praying mantis; found chiefly on seaweed
amphipod: a kind of malacostracan crustacean

skeleton shrimp (noun)	amphipod (noun)
small amphipod crustacean having a grotesque form suggestive of the praying mantis; found chiefly on seaweed	a kind of malacostracan crustacean