Mixosaurus might have been missed

IF YOU GO

The Mixosaurus fossils are on display at the W. M. Keck Museum at the Mackay School of Mines at University of Nevada, Reno. It is open Monday through Friday 9 a.m. until 4 p.m. For information, call 784-6052.

RENO - Nevada's most prominent fossil find would have been easy to miss.

It required several hours of driving and a three-mile hike, which included traversing two steep peaks, to reach the desolate site.

Located in the center of Nevada, the rich fossil find was made.

It was significant because Steve Scott, a science teacher for Clark County School District, found Mixosaurus fossils.

The reptile, referred to as a "fish lizard," is a member of the same family as the ichthyosaurus.

Other members of the ichthyosaurus family have been found in Nevada. The giant Shastasaurus, which is on display at Berlin Ichthyosaur State Park, is the most prominent and is at least 20-feet long.

The Mixosaurus, in contrast, is about 7-feet long. It lived during the Mesozoic era, about 200 million years ago. At that time, Nevada was a warm, shallow ocean, said University of Nevada, Reno, Geology Professor Jim Carr

The small reptile had a long body, a long snout, short legs and flippers and four crescent-shaped fins. Its eyes functioned like the aperture on a camera lens.

Like a turtle, the Mixosaurus lived in the water and breathed through its nostrils.

There is dispute if the reptile had a dorsal fin.

"Up to now we had the giants. Now this is the opposite. It's the tinniest," Carr said.

The fossils would have been easy to miss to the untrained eye.

Trace outlines of the Mixosaurus were found in chunks of limestone, unlike many other fossils that protrude neatly from the rock.

Over time, as the fossil is exposed to light, the outline is easier to distinguish from the dark limestone.

Scott initially went to the site in the summer of 1997 in search of ammonites.

He found the Mixosaurus head and jaw section with its teeth intact, in addition to finding ammonites - a snail-like fossil.

Scott asked Carr to go on a second trip. They found a Mixosaurus eye socket. On a third trip they found a flipper.

"It's the best find in Nevada and quite possibly the best find in North America," Carr said. "It's like walking down the street and finding a $100 bill. Although in today's terms it would be a $1,000 bill."

The two have never had to dig. The fossils were found in "float" - theloose rock that sits on the ground's surface.

Carr said the two of them spent hours trying to retrace the fossils' journey over the centuries, in the hope of finding more fossils.

Since it was "float," what followed was several hours of frantically trying to retrace the path of the fossils for 300 meters back up the hill, in hope of finding more pieces.

"Initially we thought, 'Do we really have a Mixosaurus or a juvenile Shastasaurus?' It is still possible that we have a new species of Mixosaurus. But it's definitely a Mixosaurus, that we know," Carr said.

Undoubtedly there will be more trips to the site. But the excitement of finding fossils can be marred by the arduous journey and carrying a pack full of rocks back to the car, he said.

On one trip, the car got stuck in mud, on another an oil pan on the truck was punctured. Carr said as he climbed one peak, he fell and badly cut his legs and on another, Scott hurt his back.

"It's such a rugged site. The hills are very hard and crusted, Carr said. "If I don't feel physically at my best I don't go. I wouldn't even attempt it."

The review necessary to authenticate the find will be equally challenging, Carr said, taking about two to three years.

Each fossil will be measured, weighed and diagramed. Carr said it would be useful to scan each piece to determine if fossils are present within the rocks.

This will follow peer review. Paleontologists will review the documentation before it is published.

In the meantime, Carr and his colleagues will return, scalp the site for fossils and determine if a dig is warranted.

"The site really is deserving of a scientific survey, but we have few paleontologists at UNR," he said.