Photo/Illutration An artist’s rendition of Sasayamagnomus saegusai ((c) Kanon Tanaka)

KOBE—Fossils found in Hyogo Prefecture are of a new genus and species of primitive ceratopsian, a plant-eating beaked dinosaur from about 110 million years ago, researchers said.

The research team said Sept. 3 that the dinosaur closely resembles its relatives believed to have inhabited North America, suggesting that ceratopsians born in Asia migrated to North America during the early Cretaceous Period.

According to the research team, the dinosaur was about 80 centimeters long and weighed around 10 kilograms.

It did not have a distinctive horn or frill, which were key features of triceratops and other ceratopsians.

The fossils were found in a geological formation of the early Cretaceous Period (about 110 million years ago) in Tanbasasayama, Hyogo Prefecture, which forms part of the Sasayama Group.

The dinosaur was named “Sasayamagnomus saegusai” by the research team, whose members belong to the University of Hyogo, the Museum of Nature and Human Activities, Hyogo, and the Okayama University of Science.

“Gnomus” comes from a gnome, a legendary dwarf who guards buried treasure.

“Saegusai” refers to Haruo Saegusa, a paleontologist who oversaw excavations of dinosaur fossils in the Tanba area for many years.

Part of the fossils were found in 2007 by Kiyoshi Adachi, a former high school teacher and amateur geologist. An excavation project started the following year.

Adachi, 81, and others discovered fossils of Tambatitanis, one of the largest herbivorous dinosaurs ever found in Japan, from the Sasayama Group in 2006.

Seventeen fossils, from the head, shoulder and leg of Sasayamagnomus saegusai, were unearthed by 2023.

The researchers concluded that it is a new genus and species because the fossils’ characteristics were different from those of other ceratopsians.

The findings were published in the British scientific journal Papers in Paleontology on Sept. 3.

The fossils are in the best state of preservation among ceratopsians found in Japan, according to the researchers.

The Sasayama Group has produced many dinosaur fossils.

Researchers announced in July that fossils found there in 2010 are of a new genus and species of a troodontidae, a bird-like bipedal dinosaur.

“Dinosaur fossils from the Sasayama Group have great potential,” said Tomonori Tanaka, chief researcher at the Museum of Nature and Human Activities and associate professor at the University of Hyogo. “We are looking forward to finding new animals and dinosaurs as research progresses.”

The fossils of the ceratopsian dinosaur and related materials will be on display at the museum in Sanda, Hyogo Prefecture, from Sept. 4 to Nov. 10.

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