‘Alien plant’ fossil found decades ago in Utah unrelated to any living or extinct species, new study reveals

An “alien plant” fossil discovered 55 years ago just outside of an abandoned town in Utah has no relation to any currently existing or extinct species, scientists revealed in a study last month.

Paleontologists found the fossilized leaves of the plant later dubbed Othniophyton elongatum, or ‘alien plant’ in English, in 1969. For decades, they believed that the species could be related to ginseng, a common medicinal root.

Fossilized leaves, referred to as Alien-Plant-1. Jeff Gage

Recent determinations, though, contradict that conclusion.

Steven Manchester, curator of paleobotany at the Florida Museum of Natural History and Utah fossil expert, crossed paths with an unidentified fossil while visiting the University of California, Berkeley paleobotany collection. This UC Berkeley fossil was in good condition and had come from the same area as the 1969 alien plant.

Manchester’s research team saw an opportunity and analyzed the fossils together. They determined that they were both from the same species, according to a study published in the journal Annals of Botany on Nov. 9.

Both fossils were excavated from the Green River Formation in eastern Utah, near the former town of Rainbow. Nearly 50 million years ago, the landscape in the area included a sprawling lake ecosystem and active volcanoes. Sediment produced by the lake and volcanic ash proved to be the perfect material for fossilizing parts of the ecosystem.

The researchers studied both fossils’ features and searched for living plant families with any similarities.

Unlike the 1969 fossil, the UC Berkeley specimen had leaves, flowers, and fruits attached — a stark difference from the ginseng it was assumed to be related to.

In the end, the researchers couldn’t match either fossil to more than 400 families of flowering plants existing today, on top of a slew of extinct families.

Scientists in 1969 were working only with leaves on the flowerless fossil and cooked up their ginseng conclusion on the basis of the leaves’ vein patterns and arrangement. With the detail provided by the UC Berkeley fossil, the new researchers had a more complete picture of what the plant would have looked like in its heyday and were able to disprove the ginseng connection.

The University of California, Berkeley fossilized plant remains, interpreted as a drawing. Live Science

Even so, they still could not point to any concrete family the plant could be related to.

One thing that Manchester’s team had that the 1969 discoverers lacked, though, was the gift of modern technological advancements.

They were able to use new microscopy and artificial technology to get a more detailed view of the fossils, where they found micro-impressions of developing seeds on the UC Berkeley fossil’s fruits. They also spotted stamens, or flowers’ male reproductive organs.

“Usually, stamens will fall away as the fruit develops. And this thing seems unusual in that it’s retaining the stamens at the time it has mature fruits with seeds ready to disperse. We haven’t seen that in anything modern,” Manchester said in a statement.

Even comparing the off-color stamen behavior didn’t result in any matches. However, the alien plant isn’t the first Green River Formation discovery that has stirred up trouble. Other plant fossils from the region, like Bonanzacarpum fruit and Palibinia leaves, have blown scientists away and even led to the discoveries of entire new extinct groups.