bivalve vs bivalved

bivalve is a noun but bivalved is not a noun.

Word	Noun	Adjective	Verb	Adverb
bivalve	Yes	Yes	No	No
bivalved	No	Yes	No	No

As adjectives, bivalve and bivalved are synonyms defined as:

bivalve and bivalved: used of mollusks having two shells (as clams etc.)

bivalve (noun)	bivalved (noun)
marine or freshwater mollusks having a soft body with platelike gills enclosed within two shells hinged together

bivalve (adjective)	bivalved (adjective)
used of mollusks having two shells (as clams etc.)	used of mollusks having two shells (as clams etc.)