'Alien' 47-million-year-old plant fossil found in Utah has no known relatives

Researchers compared the fossil to over 400 flowering plant families and found no match, suggesting it belongs to an unknown group.

 'Alien' 47-million-year-old plant fossil found in Utah has no known relatives. (photo credit: Florida Museum of Natural History/Jeff Gage)
'Alien' 47-million-year-old plant fossil found in Utah has no known relatives.
(photo credit: Florida Museum of Natural History/Jeff Gage)

A recent study published in the journal Annals of Botany revealed that the ancient plant Othniophyton elongatum does not belong to any known modern or extinct plant family, highlighting a mysterious lineage of flowering plants. Researchers led by Steven Manchester, curator of paleobotany at the Florida Museum of Natural History, examined well-preserved fossils that included the plant's leaves, flowers, fruits, and twigs, providing unprecedented details about this enigmatic species.

Initially discovered in 1969 in the Green River Formation in Utah, Othniophyton elongatum was thought to be related to the ginseng family, scientifically known as Araliaceae, based on the shape and vein patterns of its fossilized leaves. However, recent analyses have disproved this theory. "The peculiar combination of features of Othniophyton elongatum, including leaves, fruits, and flowers, defies its assignment to any known group. Even extinct families could not provide a match," Steven Manchester said, according to Rossiyskaya Gazeta.

The exceptional preservation of the fossil allowed scientists to observe unique characteristics not seen in other plants. In most species, stamens—the male reproductive organs—detach after fertilization. In contrast, Othniophyton elongatum retains its stamens attached to mature fruits, a highly unusual feature. "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," Steven Manchester stated, as reported by The Independent.

Advanced microscopy techniques revealed minute details such as micro-impressions of small developing seeds in the fossil fruits, shedding light on the plant's reproductive cycle. This technological advancement allowed researchers to obtain a better understanding of the exceptional characteristics of Othniophyton elongatum. Despite comparing the fossils to more than 400 families of existing flowering plants, researchers found no match, leading to the conclusion that it represents an extinct species unlike any other terrestrial plant.

The inability to fit Othniophyton elongatum into a known family or genus demonstrates the challenges in paleobotany. "There are many things for which we have good evidence to put in a modern family or genus, but you can't always shoehorn these things," Dr. Manchester remarked, according to The Independent. This issue highlights an important problem in the field: researchers often assign extinct plants less than 65 million years old to modern families or genera, which can skew estimates of biodiversity in ancient ecosystems.

The Green River Formation, where the fossils were discovered, housed a vast lake ecosystem about 47 million years ago. The combination of lacustrine sediments and volcanic ash allowed for exceptional fossil preservation, capturing fish, reptiles, birds, and plants in remarkable condition. The area has previously yielded mysterious fossils such as Bonanzacarpum fruits and Palibinia leaves, leading to the discovery of other extinct groups.

Julian Correa-Narvaez, another author of the study, emphasized the significance of the findings. "It's important because it gives us a little bit of a clue about how these organisms were evolving and adapting in different places," he said, as reported by The Independent. The study suggests that the history of flowering plants is more complicated than previously known, and the extent of lost diversity within Othniophyton elongatum's mysterious group remains unknown.

The research underscores the importance of well-preserved fossils in reconstructing extinct groups and expanding the understanding of ancient biological diversity. With modern technologies such as advanced microscopy, scientists can examine specimens with unprecedented detail, revealing information that deepens knowledge of Earth's botanical history.

Despite the extensive search, scientists have not found any modern or extinct plant families that match Othniophyton elongatum. This discovery raises questions about plant evolution and the biological diversity that existed in the past, highlighting a significant gap in the understanding of flowering plant lineages. Researchers are hopeful that future discoveries may uncover more about this enigmatic plant and its relatives.

This article was written in collaboration with generative AI company Alchemiq