Noun
flatworms
Source: WordNetBecause they do not have internal body cavities, Platyhelminthes were regarded as a primitive stage in the evolution of bilaterians (animals with bilateral symmetry and hence with distinct front and rear ends). Source: Internet
Evol Dev 11(5):582-589 Suzuki TG, Ogino K, Tsuneki K, Furuya H (2010) Phylogenetic analysis of dicyemid mesozoans (phylum Dicyemida) from innexin amino acid sequences: dicyemids are not related to Platyhelminthes. Source: Internet
Relationships with other phyla English-language writings have conventionally treated nemertean as "primitive" acoelomate bilaterians that are most closely related to flatworms (Platyhelminthes). Source: Internet
Classification and evolutionary relationships seeAlso Relationships of Platyhelminthes to other Bilateria : Note: Bold indicates members of traditional "Platyhelminthes". Source: Internet