Acoelomorpha

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{{Taxobox | color = pink | name = Acoelomorphs | image_width = 100px | image_caption = Flagellophora apelti, a nemertodermatida acoelomorpha | regnum = Animalia | subregnum = Eumetazoa | unranked_phylum = Bilateria | phylum = Acoelomorpha | phylum_authority = Baguña & Riutort, 2004 | subdivision_ranks = Classes | subdivision =

• Acoela
• Nemertodermatida

}}

The Acoelomorpha are a phylum of animals formerly considered to be in Platyhelmintha, but recently classified by Juame Baguña and Marta Riutort as a separate phylum, basal among the Bilateria. The Acoela are very small flatworms that do not have a gut. Digestion is accomplished by means of a syncytium that forms a vacuole around ingested food. There are no epithelial cells lining the digestive vacuole. All other bilateral animals have a gut lined with epithelial cells. As a result, the acoels appear to be solid-bodied (a-coel, or no body cavity). Acoels are almost entirely marine, living between grains of sediment, swimming as plankton, or crawling on algae. Acoels have a statocyst, which presumably helps them orient to gravity.

References

• Platyhelminthes The nature of a controversial phylum - retrieved February 3 2006

External links

• Phylogeny of Lower Worms of the Meiofauna (Acoelomorpha)Template:Invertebrate-stub

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