Fossil Wiki

Fossil Wiki has moved! The new site is available at YourWiki

READ MORE

Fossil Wiki
 tooth-whorl.

Helicoprion tooth-whorl.

A parasymphysial tooth whorl or spiral, is a possible gnathostome (a vertebrate animal possessing true jaws) synapomorphy(a derived character state shared by two or more taxa). This structure is more easily illustrated than explained.