beach flea vs sand flea

beach flea and sand flea both are nouns.

Word	Noun	Adjective	Verb	Adverb
beach flea	Yes	No	No	No
sand flea	Yes	No	No	No

As nouns, beach flea and sand flea are synonyms defined as:

beach flea and sand flea: small amphipod crustaceans that hop like fleas; common on ocean beaches

Other synonyms of beach flea include sand hopper, sandhopper.

beach flea (noun)	sand flea (noun)
small amphipod crustaceans that hop like fleas; common on ocean beaches	small amphipod crustaceans that hop like fleas; common on ocean beaches