Scientists have discovered that a “strange” prehistoric plant species is the lone representative of a mysterious group of organisms that no longer exists.

The first evidence of the species—in the form of fossilized leaves—appeared in eastern Utah in 1969. At the time, researchers believed the plant belonged to the ginseng family, scientifically known as Araliaceae.

But a recent evaluation of a 47-million-year-old fossil collected from the same area of ​​Utah that appears to represent the same species has shown that it does not match any surviving plant family, including the Araliaceae.

An article describing the research of prehistoric species – the so-called Othniophyton elongatumwhich translates to “alien plant” — was published in the journal Annals of Botany.

“This example shows that the vegetation around 47 million years ago included some taxa that cannot be easily classified into modern families and genera,” the authors wrote in the study.

One of the authors of the study is Steven Manchester, curator of paleobotany at the Florida Museum of Natural History, who has been studying the 47-million-year-old fossils from Utah for the past several years.

While visiting the paleobotany collection at the University of California, Berkeley, he encountered an unidentified and unusually well-preserved plant fossil originally obtained from a site near the ghost town of Rainbow in eastern Utah in the Green River Geologic Formation—same. the place where the discovery was made in 1969.

Closer observation revealed that the fossils in the Berkeley collection and the 1969 find belonged to the same plant species. The recently discovered fossil unusually preserves the plant’s flowers, fruits and twigs, as well as leaves.

“This fossil is rare in that it has a twig with fruits and leaves attached. These are usually found separately,” Manchester said in a news release.

This is in contrast to the 1969 fossil, which only preserves leaves, limiting what information can be gleaned about the plant.

In the latest study, researchers found that the Berkeley fossil has a striking combination of characters, including unusual flowers and fruits, that don’t match other plants in the ginseng family, to which the species was originally assigned after its discovery in 1969.

The authors then performed a methodical analysis to find any living or extinct plant family that the species might belong to, but were unable to find any matches.

The diversity within plant families can be remarkable. For example, species as diverse as poison ivy, cashew, and mango all belong to the same large family. The extent of lost diversity within a mysterious extinct group that Othniophyton elongatum belongs to remains unknown.

Link

Manchester, SR, Judd, WS, & Correa-Narvaez, JE (2024). Vegetative and reproductive morphology of Othniophyton elongatum (MacGinitie) gen. et comb. nov., an extinct angiosperm tree with possible caryophyll affinity from the Eocene of Colorado and Utah, USA. Annals of Botany. https://doi.org/10.1093/aob/mcae196