Members of the phylum Platyhelminthes (flatworms) lack a specialized circulatory system.
NOT BSTOTAL BS
NOT BS — Verdict: True
Verified by Lenz ·
The Short Version
The evidence strongly supports this statement. Standard biology references consistently describe Platyhelminthes as lacking a dedicated circulatory system, with gases and nutrients moving mainly by diffusion and, in larger forms, through a branched gastrovascular cavity. That cavity assists transport but does not qualify as a specialized circulatory system.
Caveats
Do not confuse nutrient distribution by a branched gastrovascular cavity with a true circulatory system.
One ambiguous low-authority outline appears contradictory, but clearer higher-quality sources overwhelmingly support the claim.
The wording matters: the claim concerns a specialized circulatory system, not whether flatworms move materials internally at all.