8 Official State Dinosaurs

Most states have a collection of symbols that their residents have chosen to represent their collective identity: flags, flowers, and birds are popular categories. A few have gone the extra mile and named official state fossils—including the eight states below, who claim their own dinosaurs.

1. Colorado // Stegosaurus
2. Kansas // Silvisaurus condrayi, Tylosaurus, and Pteranodon
3. Maryland // Astrodon johnstoni
4. Missouri // Parrosaurus missouriensis
5. New Jersey // Hadrosaurus foulkii
6. Oklahoma // Acrocanthosaurus atokensis
7. Texas // Paluxysaurus jonesi
8. Wyoming // Triceratops

Colorado // Stegosaurus

The plant-eating Stegosaurus—a genus whose name means “roof lizard”—wasn’t the most graceful-looking of dinos. With its long spiked tail, stumpy legs, and tiny triangular head, Stegosaurus struggled to coordinate the movements of its own body. Its brain was the size of a dog’s—one of the smallest relative to body size of all dinosaurs known to date.

The first Stegosaurus skeleton ever found was discovered near Morrison, Colorado, in 1877 by geologist Arthur Lakes. He sent a sample of the fossil to the famed paleontologist Othniel Marsh and asked to be hired as one of his “bone collectors,” whom Marsh employed to dig up fossils in the western U.S. Marsh seemed ambivalent, so Lakes contacted Marsh’s bitter rival, Edward Drinker Cope, with the same proposal. When Marsh heard about that, he hired Lakes immediately, winning that skirmish in his Bone Wars with Cope.

In 1982, a class of fourth-graders in Colorado succeeded in its effort to have the Stegosaurus designated the state dinosaur.

Kansas // Silvisaurus condrayi, Tylosaurus, and Pteranodon

Kansas has not one but three official state fossils, each occupying a particular niche in the prehistoric environment. Tylosaurus, a genus of of the ocean predators known as Mosasaurs, lived for a few million years just before an asteroid hit Earth and wiped out the dinosaurs 66 million years ago. Pteranodon was a genus of gigantic flying reptiles with wingspans of up to 20 feet. Both lived in the interior seaway of North America that became present-day Kansas and were named the state marine fossil and state flying fossil, respectively, in 2014.

Technically, Tylosaurus and Pteranodon are not dinosaurs. In 2023, the legislature deemed Silvisaurus condrayi, the only actual dinosaur to have lived in the territory that became Kansas, its state land fossil after a campaign spearheaded by teacher Joel Condray and his class of sixth-graders. Condray is the grandson of Warren Condray, a rancher who discovered the first S. condrayi fossil in 1955 and donated it to the University of Kansas’s Natural History Museum.

Maryland // Astrodon johnstoni

Maryland’s state dinosaur may be the only species discovered by a chemist and named by a dentist. In 1858, State Agricultural Chemist Philip Tyson was out in the field compiling data for Maryland’s first geologic map when he found two unusual fossilized teeth in the clay of Prince George’s County, just east of Washington, D.C. He turned them over to local dentist Christopher Johnston for analysis. Johnston cross-sectioned one of the teeth and found a star-like pattern in the tissue, which led him to suggest the new genus Astrodon (“star-tooth”) for the fossil.

The teeth represented one of the United States’ earliest fossil discoveries and the first found in Maryland. A. johnstoni was a sauropod, a giant herbivore with a super-long neck and tail, chunky body, and thick legs that lived about 95 to 130 million years ago. It was deemed Maryland’s state dinosaur in 1998.

Missouri // Parrosaurus missouriensis

Parrosaurus missouriensis (formerly Hypsibema missouriensis), discovered in 1942 in the Ozarks, was the first dinosaur remains found in the state of Missouri. Geologist Daniel Stewart met a young boy named Ole Chronister near the town of Glen Allen who said his family had found some odd rocks when they were digging a well. Stewart examined the finds and realized they were fossils; eventually, the Chronisters sold most of them to the Smithsonian. The animal has since been classified as a hadrosaur, a duck-billed dinosaur that sported more than 1000 teeth. P. missouriensis was named the state dinosaur in 2004 under its previous scientific name.

New Jersey // Hadrosaurus foulkii

In 1858, fossil hobbyist William Parker Foulke and paleontologist Joseph Leidy unearthed the first nearly-complete dinosaur skeleton found in the United States on a farm Haddonfield, New Jersey. The farm’s owner had been digging up bones for two decades and had even given some away as objects of curiosity.

In 1868, visitors were invited to view the bones on display at the Academy of Sciences in Philadelphia, granting the remains the secondary distinction of being the first dinosaur skeleton mounted for public exhibition. The display was so popular, drawing in more than three times the museum’s usual crowd within the first few years alone, that the institution relocated to a larger facility. In 1879, Foulke’s namesake duck-billed dinosaur went international: Edinburgh’s Royal Scottish Museum acquired a copy of the skeleton, which became Europe’s first dinosaur exhibit. Thanks to its global fame and local appeal, New Jersey named H. foulkii its state dinosaur in 1991 after a campaign by Joyce Berry, an elementary school teacher in Haddon Township, and her many fourth-grade students.

Oklahoma // Acrocanthosaurus atokensis

Oklahoma’s state dinosaur obtained its official state adoption in 2006, though its existence dates to the Early Cretaceous period. A. atokensis is the only named species within its genus; its species name pays homage to Atoka County, where its fossil specimens were first discovered in 1940. Acrocanthosaurus means “high-spined lizard” and refers to the distinctive neural spines projecting from the dinosaur’s vertebrae, but its claws were the feature to fear: Measuring up to 6 inches long, they were designed to grip its prey and tear flesh from bone.

Texas // Paluxysaurus jonesi

Texas’s official dinosaur has gone through an identity crisis in recent decades. In 1997, Governor George W. Bush signed a resolution designating Pleurocoelus (a former name for Astrodon) the “official Lone Star State dinosaur,” citing evidence of footprints and bones found primarily within modern state lines and declaring it “indigenous to Texas.” Seven years later, graduate student Peter Rose identified the Pleurocoelus fossils as an entirely new genus and species, Paluxysaurus jonesi, named for the town and ranch where the bones were originally discovered. Governor Rick Perry signed a bill to make the change official in 2009.

With its neck extended, Paluxysaurus jonesi could reach 56 feet tall, making it one of the tallest known dinosaurs, and at 56 tons, one of the heaviest as well.

Wyoming // Triceratops

A year after the release of the film adaptation of Michael Crichton’s Jurassic Park, Wyoming claimed the three-horned, frill-necked Triceratops as one of its own. A 1994 statute declared, “A state dinosaur shall be designated by election in accordance with the law. The results of the election naming the state dinosaur shall be filed with the secretary of state.” The election in question was a poll of elementary school children, who may have voted for the Triceratops out of sympathy for the sick beast in Spielberg’s classic movie.

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A version of this story was published in 2013; it has been updated for 2025.