Photograph by Matt Friedman

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The new species Natgeosocus sorini is known only from this one fossil of a young fish.

Photograph by Matt Friedman

Peculiar Extinct Fish With Spines Named for National Geographic

Natgeosocus sorini swam in subtropical seas about 36 million years ago, a new study says.

There may be plenty of fish names in the sea, but Alexander Bannikov decided to honor National Geographic with the one that he just added to the community of ancient marine creatures.

The paleontologist and his team unearthed the fossilized skeleton of a new genus—and species—of extinct bony fish in southwestern Russia in 2013. Since their expedition was funded by National Geographic's Committee for Research and Exploration, the discovery was dubbed Natgeosocus sorini. (Also see "Fish Fossil Has Oldest Known Face, May Influence Evolution.")

Here's how the name breaks down: Natgeosocus is the name of the new genus. Sorini is the new species, a nod to Romanian paleoichthyologist Dorin-Sorin Baciu, who extricated the skeleton from the clay that encased it.

Finding the fish was "a great surprise for me," because the only relative of the new genus lives in Denmark and is 20 million years older, said Bannikov, of the Russian Academy of Sciences' Paleontological Institute, in an email.

Inspiration for Sea Serpents

Natgeosocus sorini liked it hot, dwelling in the subtropical seas off southeastern Europe about 36 million years ago, during the Eocene period, according to a study published in November in the Paleontological Journal. (See a prehistoric time line.)

The species likely swam alongside many well-known modern fish such as herring, cod, and mackerel, Bannikov said, as well as other species in its own family, Palaeocentrotidae, which is now extinct. (A family is the taxonomic ranking above genus.)

Members of Palaeocentrotidae were not only rare, but had "extraordinarily peculiar" physical characteristics, he added.

For instance, the new species has spines in the middle of its dorsal fin, which is highly unusual, Bannikov said. (See "Ancient Fish Downsized But Still Largest Ever.")

N. sorini is also a type of lampridiform, a relatively small order of fish that includes 21 living species with a range of body shapes and sizes. Many of the species are rare.

Oarfish—rarely seen, bizarre, deep-sea creatures that are thought to have inspired legends of sea serpents—are a type of lampridiform. (Related: "Rare Video Shows 'Sea Serpent' Oarfish in Shallow Water.")

Overall, finding such a rare, unexpected species helps illuminate the murky world of Palaeocentrotidae and lampridiforms, Bannikov said.

As for whether he'll name another fish after National Geographic, he said, "Why not? In 2002 I named a new species of yellowtail Seriola natgeosoc."

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