ostracod vs mussel shrimp

ostracod and mussel shrimp both are nouns.

Word	Noun	Adjective	Verb	Adverb
ostracod	Yes	No	No	No
mussel shrimp	Yes	No	No	No

As nouns, ostracod and mussel shrimp are synonyms defined as:

ostracod and mussel shrimp: tiny marine and freshwater crustaceans with a shrimp-like body enclosed in a bivalve shell

Other synonyms of ostracod include seed shrimp.

ostracod (noun)	mussel shrimp (noun)
tiny marine and freshwater crustaceans with a shrimp-like body enclosed in a bivalve shell	tiny marine and freshwater crustaceans with a shrimp-like body enclosed in a bivalve shell