A phylum based on Trichoplax adhaerens, a small, multicellular organism first discovered in 1883 in a marine aquarium in Naples; since then two more species have been discovered.T. adhaerens is flat, amoeboid, 2–3 mm in diameter, and has a dorsal and ventral layer of ciliated (cilium) cells with a layer of loose, contractile cells between. It produces eggs and also reproduces by fission and budding. The DNA content is less than that in any other animal.
Subjects: Zoology and Animal Sciences.