Californosaurus perrini ('Perrin's California lizard') was an ichthyosaur

Ichthyosaur

Ichthyosaurs were giant marine reptiles that resembled fish and dolphins...

, an extinct reptile, from the Lower Hosselkus Limestone (Carnian

Carnian

The Carnian is the lowermost stage of the Upper Triassic series . It lasted from about 228.7 till 216.5 million years ago . The Carnian is preceded by the Ladinian and is followed by the Norian...

, Late Triassic

Late Triassic

The Late Triassic is in the geologic timescale the third and final of three epochs of the Triassic period. The corresponding series is known as the Upper Triassic. In the past it was sometimes called the Keuper, after a German lithostratigraphic group that has a roughly corresponding age...

) of California. It has also been known as Shastasaurus

Shastasaurus

Shastasaurus is an extinct genus of ichthyosaur from the middle and late Triassic, and is the largest marine reptile that has yet been found. Specimens have been reported from the United States, Canada, and China...

 perrini and Delphinosaurus ('dolphin lizard') perrini. It is the basal-most known true ichthyosaur (Euichthyosauria). The long-snouted head is small in comparison with the rest of the body, as in basal ichthyosaurs such as Mixosaurus

Mixosaurus

Mixosaurus is an extinct genus of ichthyosaur. Fossils of Mixosaurus have been found all over the world - China, Timor, Indonesia, Italy, Spitsbergen, Svalbard, Canada, Alaska, and Nevada. It was named in 1887 by George H. Baur...

and Cymbospondylus

Cymbospondylus

Cymbospondylus was a basal early ichthyosaur that lived between the middle and later years of the Triassic period...

. The tail is sharply turned downwards, in common with more advanced ichthyosaurs, with a small vertical fluke. It may have had a small dorsal fin. There is a small number of pre-sacral vertebrae (45 or 50). The phalanges (digit bones) are circular and widely spaced, giving the flipper a round appearance. It was three metres long. It fed on fish and other small marine creatures. Like other ichthyosaurs it probably never ventured onto dry land, and gave birth in the water.

Websites

• Palaeos Vertebrates http://www.palaeos.com/Vertebrates/Units/210Eureptilia/400.html
• Ichthyosaurus http://home.scarlet.be/ichthyosaurus/californopas.html