Undata
Undata is a genus of extinct cephalopods belonging to the subclass Nautiloidea. These marine invertebrates lived during the Devonian period, approximately 419 to 359 million years ago. Fossils of undata have been found in various parts of the world, indicating a widespread distribution. The genus is characterized by its distinctively coiled shell, which typically displays a broad, flattened, and somewhat evolute form. The whorls are usually closely spaced, and the shell often exhibits prominent ribbing or ornamentation, which can vary in strength and pattern among different species. The aperture, or opening of the shell, is generally wide. Like other nautiloids, undata possessed a siphuncle, a tube that ran through the camerae (chambers) of its shell, allowing it to control its buoyancy in the water column. The exact lifestyle of undata is not fully understood, but its shell morphology suggests it was likely a nektonic or benthonic organism, capable of active movement or dwelling on the seafloor. Its diet likely consisted of smaller marine invertebrates. The study of undata and other Devonian nautiloids provides valuable insights into the early evolution and diversity of cephalopods.