It’s been a while since we had a new topic here so I’d thought I’d post an image of Nipponites, arguably the weirdest and most derived form of ammonite that evolved. Nipponites is known from the Late Cretaceous period from Japan (approx 93-85 mya) and is clearly peculiar as the shell did not grow in the usual spiral shape but in a series of ‘U’ bends alternating in the X, Y and Z axis. The result was a shell resembling a nightmarish twisted mass. The shell still contained the complex ammonite suture lines between the body chambers and had simple ribs. The final chamber of the shell was slightly recurved and would have hung below the shell so that the head of the animal would have been angled somewhat downwards. As one can imagine, the ammonite would have been a very poor swimmer as demonstrated by its non-streamlined shell. Some researchers think that Nipponites would have been jellyfish-like in its feeding habits, hanging and drifting in the open water, ensnaring small animals with long trailing tentacles.