Onirocolia

The order Onirocolia is the sister taxon of stegocaudates. The tubular shell in which their digestive and branchial zooids live grows curved, although in these organisms it take much more sinuous and intricate forms than their relatives. In some cases, the patterns are completely surreal to look at. Most extant onirocolians are adapted to a sedentary lifestyle, although some genera retain the ancestral swimming ability of the taxon. Both sessile and pelagic genera can control their buoyancy thanks to internal gas bladders.

The two images on the left correspond to two different species of the genus Onirocola. They are suspension feeders and live clinging to reefs using their caudal zooid, and floating like a balloon. The sizes of this diverse genus vary between 5 to 60 cm in width.

Top right, a Enterolites 3 cm long. It is a predator adapted to hunt hive sponge drones.

Bottom right, the detritivore Mesophidium. This 8 cm long genus lives in soft and muddy bottoms where it can bury in case of danger.