Protobranchia

plural noun

Pro·​to·​branchia

: an order of Lamellibranchia comprising primitive bivalve mollusks in which the gills consist of a double row of simple lamellae not reflected or united

protobranchiate

¦⸗(ˌ)⸗+

adjective

Word History

Etymology

New Latin, from prot- + -branchia

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