Plesiotylosaurus (related animal)

Name Meaning: Desert Lizard

Geologic Era:  Late Cretaceous

Location Found:  Morocco

Estimated Range:  Modern North Africa

Size:  Unknown, probably a middle sized mosasaur

Extinction Date:  65 million years ago (K-T extinction)

Eremiasaurus is still relatively poorly understood, and known from only fragmentary remains.  All that has been recovered are partial skulls and vertebral columns from two individuals.  While it can still be determined that Eremiasaurus was a mosasaur, its exact appearance remains something of a mystery.  It was probably much smaller than animals like Prognathodon or Mosasaurus, but still would have been a predator in its own right.  Possible prey items could have included smaller sharks, fish, or other smaller marine reptiles.  

One feature that sets Eremiasaurus apart from many mosasaur species is that it has several shapes of teeth in its mouth.  That is where the species name “heterodontus” comes from.  What this probably means is that Eremiasaurus was a generalist predator, eating whatever it could easily catch.  This is unlike many other mosasaur species, which favored certain prey items.  One species in particular, Globidens, has round, blunt teeth.  These teeth would have been next to useless for catching fish, but would have been ideal for cracking the shells on ammonites, nautaloids, or turtles.  More pointed teeth like Eremiasaurus would have been better suited to fish or smaller marine reptiles.

Plotosaurus (related animal)

Image Credits:

Life Restoration:  By DiBgd – Own work, CC BY-SA 4.0, Life Restoration:  https://commons.wikimedia.org/w/index.php?curid=42204195

Skeleton:  By Gleep!! from USA – Sea Serpents.Uploaded by FunkMonk, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=27592106