|Blue Button, Porpita porpita|
The most familiar members of the family Porpitidae are the Blue Button (Porpita porpita) and the By-the-wind Sailor (Velella velella).
Structure[change | change source]
Chondrophores may look like a jellyfish, but they really are not. Like the siphonophores they are not a single animal. They are a colony of clones, genetically identical zooids. These zooids are small, highly modified individual polyps. Though structurally similar to other cnidarians, the zooids do not live by themselves: they are attached to each other. Each type of zooid depends for survival on the others doing what it cannot do by itself.
Fossil record[change | change source]
A rare soft-bodied fossil was got from Mississippian strata in northeastern Kentucky. It was interpreted as a chondrophorine float. The origin of the group was probably in the Neoproterozoic era, some 650–540 million years ago.