Prague Metro D excavation reveals ancient fossil 'unknown to science'

A rare fossil discovered during the construction of Prague’s Metro D line has been identified as a completely new species of ancient arthropod, challenging previous scientific understanding of prehistoric life.

The creature, named Soomaspis labutai, lived approximately 448 million years ago and represents a rare link to species previously thought to exist only in the Southern Hemisphere.

The find was made by Radek Labuť, a fossil collector and owner of the Trilopark museum, who spotted the specimen in a pile of excavated rubble from the subway worksite.

Measuring just two centimeters, the fossil was initially mistaken for a common trilobite before being analyzed by experts at the Geological Institute of the Czech Academy of Sciences.

"It turned out to be a species previously unknown to science," Lukáš Laibl of the Geological Institute said in a press release. "Unlike trilobites, it had only a soft shell. We named it in honor of its discoverer."

Despite being found in a discard pile, researchers from the National Museum were able to pinpoint its origin.

"I have been following the excavation of Metro D for a long time and keep detailed documentation of rocks in every part of the tunnel," said co-author Jana Bruthansová.

She confirmed the fossil originated from the Králodvor Formation, dating to the late Ordovician period, just before Earth's first mass extinction.

The discovery comes as a surprise to the science community because the only known relative of the genus, Soomaspis splendida, was discovered in South Africa.

Scientists previously believed the genus was a local endemic species limited to that region.

"Today's Prague and South Africa were thousands of kilometers apart at the time," Laibl noted. "Finding this in Prague is like discovering a Japanese giant crab in the Vltava River."

The research suggests that these inconspicuous arthropods were "survivors" capable of enduring extreme climate fluctuations. By inhabiting deep-sea environments with low oxygen levels, they managed to survive the onset of the Ordovician Ice Age, which wiped out much of the planet's marine life.

Following the conclusion of the study, which involved collaborators from Charles University and Flinders University in Australia, the fossil has been donated to the National Museum. It is expected to be placed on permanent display for the public later this year.

Czechia’s strong connection to trilobites is rooted in its geology and long scientific tradition.

Much of Prague sits on Paleozoic rock, meaning fossils are regularly uncovered during construction projects. The country also has more than 230 years of paleontological research, shaped in part by 19th-century scientist Joachim Barrande, with the Barrandian region remaining a key global site for Early Paleozoic studies.

A dedicated community of amateur collectors and private museums reflects the unusually broad public engagement with fossil hunting in Czechia.