🪼 New quasi-jellyfish species discovered near Quebec City

Researchers studying 450-million-year-old fossils discovered about 31 miles (50 kilometers) northeast of Quebec City have identified a new species of basal medusozoan: *Paleocanna tentaculum*, a soft-bodied tubular polyp with a ring of tentacles.

The discovery of this organism, very close to modern jellyfish, is an event in itself, since only a few species of its subphylum have been recorded in the fossil record.


"Soft-bodied organisms do not preserve as well as hard-bodied organisms, which makes soft-bodied fossils all the more valuable for understanding the history of life," explains Louis-Philippe Bateman, co-author of the study and a graduate student in the Department of Biology at McGill University.

According to the co-author, this discovery also highlights the importance of Quebec's fossil heritage.

"I've often said that our fossil deposits are less prestigious than those in regions like British Columbia or Alberta," he adds. "Discoveries like this prove that there is still much to discover and study here."

A species-rich site The fossils were discovered in Saint-Joachim, in the upper part of the Neuville Formation, in the St. Lawrence Lowlands. According to Christopher Cameron, co-author of the study and a biology professor at the Université de Montréal, this region ranks "among the most species-rich fossil sites on the planet" for Ordovician fossils.

The research team examined fifteen slabs of shaly limestone containing approximately 135 specimens, 39 of which were measured and photographed. To carry out this identification, they compared the physical characteristics of the fossils with those of 69 other species, fossil or living, related to jellyfish.

The analysis showed that *Paleocanna tentaculum* was closer to modern jellyfish than to other related ancient organisms.

Exceptional state of preservation According to the researchers, these fossils were likely created by sudden burial on the seafloor, when fine mud quickly covered the animals, thus protecting them from scavengers and disturbances.

"Given that several individuals are oriented in the same direction, we think they were buried in place or were not transported far before being covered," notes Greta Ramirez-Guerrero, lead author and doctoral student at the Université de Montréal. "This rapid burial, combined with an oxygen-poor environment, slowed decomposition and helped preserve the animals before the sediments turned into rock."


These fossil specimens are stored at the Musée de paléontologie et de l'évolution (MPE) in Montreal, where they will be the subject of further research.

"We must pay tribute to John Iellamo, a renowned amateur fossil collector and member of our museum, who discovered these fossils in 2010 and donated them to the MPE," says Mario Cournoyer, co-author of the study and founder of the MPE. "He recognized the scientific importance of these fossils and made them available to researchers. Without him, we would not be talking about this new species."

Louis-Philippe Bateman adds that the Saint-Joachim site may hold other secrets. "On this type of site, you generally find interesting species for many years. So I expect many more spectacular discoveries."