Coryloides facts for kids

Coryloides is an extinct plant that lived a very long time ago. It was a type of flowering plant and was related to today's hazelnut trees. Scientists know about it from a single species called Coryloides hancockii. This plant is only known from its fossil nuts found in Oregon, USA. These fossils tell us a lot about what plants were like millions of years ago.

Discovering Coryloides hancockii

Where These Ancient Nuts Were Found

The only place Coryloides hancockii has been found is in a special area in Oregon. This area is part of the John Day Fossil Beds National Monument. It's called the Clarno nut beds. This spot is very important because it's where both the rock formation and the plant species were first identified.

The Clarno nut beds are about 3 kilometers (2 miles) east of a small community called Clarno, Oregon. Scientists believe these rocks and fossils are from the middle Eocene period. This means they are about 43 to 45 million years old! Scientists figured this out by using special dating methods. These methods measure tiny bits of radioactive material in the rocks.

The rocks in the Clarno nut beds are made of sand, silt, and pebbles mixed with volcanic ash. This area might have been a lake delta long ago. Or, it could have been a place with floods and volcanic mudflows, along with hot springs. All these conditions helped preserve the plant fossils.

How Scientists Studied the Fossils

Scientists found many Coryloides hancockii fossils. They had a main fossil, called a holotype, and many other similar fossils, called paratypes. These fossils are now kept in museums and universities. Some are at the University of Florida, others at the National Museum of Natural History, and a few more at other places like the Burke Museum of Natural History and Culture.

Many people helped collect these fossils between 1942 and 1989. This included scientists like Steven R. Manchester and Alonzo W. Hancock. Even high school students helped out! They collected about 20,000 fossils in total from this amazing site.

A scientist named Steven R. Manchester from the University of Florida studied the Coryloides fossils. In 1994, he officially described the new species, C. hancockii, in a science journal. He named the plant Coryloides because its nuts looked a lot like modern Corylus (hazelnut) nuts. The second part of the name, hancockii, was chosen to honor Alonzo W. Hancock. Alonzo was an amateur fossil hunter who helped set up the research station near the Clarno Nut Beds.

Scientists think Coryloides might have been a close relative of hazelnuts. Or, it could be an example of different plants developing similar features over time, which is called parallel evolution.

What the Coryloides Nuts Looked Like

The nuts of Coryloides hancockii were almost perfectly round. They were rounded at both the top and bottom. These nuts were quite large, measuring about 2.5 to 3.8 centimeters (1 to 1.5 inches) long. Their width was about 2.3 to 3.3 centimeters (0.9 to 1.3 inches).

Each nut had only one seed inside. The outside of the nut had strong ridges running from the top to the bottom. These ridges were spaced about 2 to 4 millimeters (0.08 to 0.16 inches) apart. The nut's outer wall was fairly thick, about 0.8 to 1.2 millimeters (0.03 to 0.05 inches).

At the bottom of the nut, there was a large round scar. This scar was about 20 to 25 millimeters (0.8 to 1 inch) wide. At the top, there was a small bump, about 1.5 to 2.5 millimeters (0.06 to 0.1 inches) wide.

Many of these features, like having one seed, the round scar, and how the plant's "veins" were arranged, are also seen in modern hazelnut trees. However, Coryloides nuts were much larger and more perfectly round than any modern hazelnut. This makes them unique and helps scientists understand how plants have changed over millions of years.