Did you know that the 1977 Nevada Legislature designated the official State Fossil to be an ichthyosaur? In 1989 this statute was amended to specify this state symbol as Shonisaurus popularis.
There are two well-known examples of fossil marine reptiles called ichthyosaurs from Nevada. Specimens of one type have been found in the Humboldt Mountains near Lovelock. This animal, Cymbospondylus petrinus, is considerably smaller than the second, Shonisaurus popularis. At a maximum approximate length of 50 feet and weighing an estimated 35 tons, this latter species is one of the largest known ichthyosaurs. All examples of this animal are from Berlin-Ichthyosaur State Park in the Shoshone Mountains of central Nevada near the site of the historic mining town of Berlin.
The images below show a fossilized centrum (main body of a vertebra) of a mature Shonisaurus popularis.
The Nevada State Museum thanks personnel of Berlin Ichthyosaur State Park for donation of this specimen.
The Nevada State Museum would also like to thanks Luka Starmer from the University of Nevada, Reno’s Libraries @One Department, for the 3D image.
This specimen is 3.5 inches thick and 7 inches in diameter. A comparable centrum from the Cymbospondylus petrinus would only be an estimated 2 inches thick and 4 inches in diameter.
Visible on one side of the Shonisaurus centrum are two vertebral spines (denoted by *) that, in life, were attached to the tops of successive centra.