

Name: Cretoxyrhina
(Cretaceous jaws).
Phonetic: Creh-tox-ee-rye-nah.
Named By: Louis Agassiz - 1843.
Classification: Chordata, Chondrichthyes,
Elasmobranchii, Selachimorpha, Lamniformes, Cretoxyrhinidae.
Species: C. mantelli.
Type: Carnivore.
Size: Up to 7 meters long.
Known locations: Worldwide.
Time period: Cenomanian to Campanian of the
Cretaceous.
Fossil representation: Usually teeth, but some
impressions revealing the cartilaginous skeleton are also known.
Also
known as the 'Ginsu shark', Cretoxyrhina was the
biggest shark of its
time, considerably bigger even than its contemporary
Squalicorax.
Cretoxyrhina was near the top of the food chain, and
it had a diet that
included almost anything that was in front of it, including mosasaurs.
There is also strong evidence for its predation of the bony fish
Xiphactinus,
a four to six meter long predator itself, and even the
large turtles of the day were fair game for Cretoxyrhina.
Cretoxyrhina
acquired the name 'Ginsu Shark' in reference to its teeth. At up to
seven centimetres long, the teeth are smooth and have thick enamel,
suggesting that they were for work against tough shells and bones. Like
the advert for Ginsu knifes said, they could cut through anything, and
Cretoxyrhina probably had little difficulty in
removing bite sized
chunks from whatever prey item it chose.
The
overall morphology for Cretoxyrhina is lamniform,
similar to a Great
White shark today. The tail also shows adaption form fast swimming,
enabling Cretoxyrhina to give chase after faster
prey.
![]() |
![]() |
![]() |
![]() |