Kardiasperma facts for kids

Kardiasperma is an extinct group of flowering plants that belonged to the hazelnut family, called Betulaceae. It includes only one known species, Kardiasperma parvum. This ancient plant is known only from its fossil nuts. These fossils were found in rocks from the Eocene epoch, about 45 to 43 million years ago, in north-central Oregon, USA.

Discovering an Ancient Plant

The fossils of Kardiasperma parvum were found in a special place called the Clarno Formation. This area is known for its amazing fossil beds, which are like a window into Earth's past. The nut beds, where these fossils were found, are about 3 kilometers (1.9 miles) east of a small community called Clarno, Oregon.

Scientists have used different methods to figure out how old these fossils are. They used techniques like zircon fission track dating and argon–argon dating. These methods showed that the fossils are from about 45 to 43 million years ago. At that time, the area might have been a lake delta or a place with volcanic mudflows and hot springs.

Many of the Kardiasperma fossils are kept in museums. The main fossil, called the holotype, is at the National Museum of Natural History in Washington, D.C.. Other fossils, called paratypes, are also in this museum, as well as at the University of Florida and the University of California Museum of Paleontology. These fossils were collected over many years by different people, including scientists and even high school students!

What's in a Name?

A scientist named Steven R. Manchester from the University of Florida studied the Kardiasperma fossils. He officially described the species in 1994 in a science journal called Palaeontographica Americana.

The name Kardiasperma comes from two Greek words: Kardia, which means "heart," and sperma, which means "seed." The second part of the name, parvum, is Latin for "small." This name was chosen because the fossil seeds were quite small.

Scientists noticed that Kardiasperma fossils look very similar to another extinct plant called Palaeocarpinus, which was found in North Dakota. However, Kardiasperma nuts are much smaller. Also, Kardiasperma nuts don't have a special leaf-like structure called a bract around them, which Palaeocarpinus does.

What Did It Look Like?

The fossil nuts of Kardiasperma parvum are generally shaped like an upside-down heart. They have a rounded bottom and a slightly pointed top. These nuts were quite tiny, measuring between 1.3 to 2.4 millimeters (0.05 to 0.09 inches) long. Their widest part was about 1.0 to 2.0 millimeters (0.04 to 0.08 inches) across.

The outside of the nut was smooth. It had a raised line, like a small ridge, running along its main side. There was also a groove, or a small channel, running down the middle of the nut from top to bottom.