They are so unlike any known animal that its discovery by Danish scientists in 1995 led to the creation of a new phylum.
The Cycliophora are a new phylum, based on a single genus Symbion.
They were discovered in 1995, and are the most recent new phylum.
This was the first new phylum of multicelled organism to be discovered since the Loricifera in 1983.
The name of the new phylum is Cycliophora, Greek for "carrying a small wheel."
The last new phylum - of another type of microscopic marine creature - was proposed in 1983.
There is no formal arbiter of categories, and a new phylum only gains credibility with general acceptance.
They are probably a new phylum.
A new phylum of fungi is announced, and named cryptomycota ("hidden fungi").
"A new brachiopod from Northern Ireland is no competition for a new phylum."