• From late Devonian to late Jurassic there were two shark groups, the Hybodonts and the Xenacanths 
  • The Xenacanths were freshwater sharks and were very abundant
  • They are identified most easily from their characteristic teeth, which have two pointed, elongate lateral cusps with one smaller cusp in the middle
  • Long “head to tail” dorsal fin and very often a large spine protruded from behind the braincase (Fenton and Fenton)
  • Some got larger than 2 m
Drawing by Stefan Grambart (phenom@cyberus.ca)
copyright Stefan Grambart, 1999