Category: Dinosaur

Ichthyosaurus (Ick-thee-oh-sore-us), fish lizard, lived in the Early Jurassic of Europe. Ichthyosaurus first evolved in the Early Triassic with eel-like bodies. They suffered a major extinction at the end of the Triassic. New species evolved in the Early Jurassic with a more fish-style body. Ichthyosaurs lasted from the Early Jurassic to the first part of the Late Cretaceous when the oceans suffered from anoxia.



Genera and Species

Classification: Ichthyosauria, ‬Ichthyosauridae.

Species: ‬I. ‬communis ,‬I. ‬breviceps, ‬I. ‬conybeari, ‬I. ‬intermedius.


Ichthyosaurs of the Jurassic were widespread; fish, squid and even small reptiles would have been on the menu. The streamlined bodies would have been fast, allowing them to chase down prey with ease (Dixon, 2006).


LENGTH: 3 m (6.5 ft).

WEIGHT: 200 lbs.


The physical convergence with dolphins, tuna and sharks makes it likely that ichthyosaurs filled a similar ecological role. They hunted fast-swimming prey in the open oceans and in the depths. Ichthyosaurs gave birth to live young. The young were born head first to prevent drowning.

History of Discovery

Discovery, 1821 by Conybeare & De la Beche; known from hundreds of specimens, ‬some articulated. ‬Skin impressions have also been recovered in some specimens, which reveal features such as the back and tail ‬fins.


Found in Europe; evolved to hunt in the depths of the open oceans for fish and squid where the large eyes would have been useful in the dark.


  1. Dixon, D. (2006). The Complete Book of Dinosaurs (pp. 10-12). London UK: Hermes House.
  2. Ichthyosaurus. (n.d.).
  3. Pleasiosauria. (20130, June 23). Ichthyosaurus.