Animal Phyla/Acoelomorpha

Acoelomorpha
Name Meaning: With gut
English Common Name: Acoels
Major distinguishing characteristics: No mouth or alimentary canal
Approximate number of species described: unknown

Natural History

All but two freshwater species are marine. All are aquatic. They live between the grains of sand, in the water column as plankton, or crawling on the substrate or other organisms.

Taxonomy

Some consider this group to be a Subphylum of Xenacoelomorpha.

There are two Classes that traditionally belong to the Phylum regardless of their placement.

Acoela
Nemertodermatida

Anatomy

The Acoelomorpha resemble flat worms. Their internal structures are so simple they have no real internal structures.

The Fossil Record

There is no known fossil record.

Quiz

Acoelomorpha Quiz

References and Further Reading

Acoelomorpha on Encyclopedia of Life
Acoelomorpha at Wikipedia