What three characteristics do proboscis worms have that are not found in other "flatworms"?
alimentary canal, closed circulatory system, and fluid sac
Why is their phylogenetic position being debated?
fluid sac that some suggest is an early coelom
Where are they found?
Tropics and subtropics
What habitats are they found in?
Ocean
What phylum is it under and what is another name for these organisms?
Phylum: Nemertea
called proboscis worm
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