Temnodontosaurus was an ichthyosaur from the early Jurassic, some 196 to 190 million years ago. It was found in England by Mary Anning, and later in Germany. It was, in fact, her first ichthyosaur. Her brother found the skull, and she found the rest of the skeleton, in about 1810. It was described in 1814.
Temporal range: Lower Jurassic
|Wall-mounted skeleton of Temnodontosaurus platyodon, with puny humans reflected in the glass. Natural History Museum, London.|
This huge ichthyosaur cruised the shallow seas hunting. But hunting what? A discussion by Christopher McGowan suggests that other reptiles might have been on the menu. McGowan also mentions that in the museum collections are some teeth and bones which suggest even larger ichthyosaurs existed.
Eye size change
Ichthyosaurs hold the record for eye size: the largest was 264mm in diameter (~10.4 inches), from the species Temnodontosaurus platyodon. This is the largest eye ever recorded for any vertebrate; the colossal squid eye is larger still. The eyes are surrounded by sclerotic rings, a kind of bony support.
- The first-found species, T. platyodon, is the smallest one.
- McGowan, Christopher 1997. The raptor and the lamb: predators and prey in the living world. Henry Holt and Penguin, p192. ISBN 0-14-027264-X
- David Attenborough on Temnodontosaurus. 
- University of California Museum of Paleontology: Motani's Ichthyosaur page