Fun Styxosaurus Facts For Kids

The Styxosaurus was a Plesiosaurus that belonged to the Elasmosauridae family. It lived during the late Cretaceous period in the Campanian stage, about 85-70 million years ago. The first type specimen (Styxosaurus browni) was located in Logan County in Hell Creek in Kansas. Another Styxosaurus skeletal specimen (Styxosaurus browni) was also discovered and unearthed in the United States, but in Iona, South Dakota. The Styxosaurus was a marine dinosaur, and it lived in oceans, seas, and coastal waters around what is today the North American continent. A peculiar and recognizable feature of the Styxosaurus was that it had a long neck that was almost half the size of its body. It had a small head and large fins that helped with locomotion. The Styxosaurus, when compared to today's massive sea creatures, is shorter than sperm whales and as heavy as killer whales. The Styxosaurus also had sharp, conical teeth which could only capture and puncture fish prey. It also had gastroliths in its belly and in its stomach that aided with digestion.

For more relatable content, check out these Orodromeus facts and Caviramus facts for kids.

How do you pronounce 'Styxosaurus'?

Styxosaurus is pronounced as 'sticks-oh-sore-us'.

What type of dinosaur was a Styxosaurus?

The Styxosaurus (Styxosaurus browni or Styxosaurus snowii) was a Plesiosaur and belonged to the family Elasmosauridae.

In which geological period did the Styxosaurus roam the Earth?

The Styxosaurus (Styxosaurus browni or Styxosaurus snowii) was alive during the Campanian stage of the late Cretaceous period, 85-70 million years ago.

When did the Styxosaurus become extinct?

The Styxosaurus (Styxosaurus snowii or Styxosaurus browni) went extinct about 70 million years ago.

Where did a Styxosaurus live?

Styxosaurus fossils were found in Logan County's Hell Creek in western Kansas, in the USA. A different and more complete specimen of Styxosaurus was uncovered in another part of the US in Iona, South Dakota.

The Styxosaurus can be said to have lived near waters of what is today known as the North American continent.

What was a Styxosaurus' habitat?

The Styxosaurus (Styxosaurus snowii or Syxosaurus browni) was a marine dinosaur, so it lived in bodies of water like seas and oceans. It is also known to have inhabited coastal waters near shores.

Who did a Styxosaurus live with?

It is possible that the Styxosaurus lived and hunted together in packs or herds. Parental care or family systems may not have existed, and it also may have been a solitary animal.

How long did a Styxosaurus live?

It is not clear how long the Styxosaurus lived.

How did they reproduce?

Unlike other terrestrial dinosaurs, the marine late Cretaceous-era Styxosaurus reproduced by mating and giving birth to live young.

What did a Styxosaurus look like?

The Styxosaurus was a huge Plesiosaur and Elasmosaur. The neck of the Styxosaur was about half its body length and contained 60-72 vertebrae.

The Styxosaurus had sharp and conical teeth. These teeth were suited to hold and puncture bodies of prey, but not for cutting. Because of this, the Styxosaurus swallowed its food whole, unlike other Plesiosaurs. Also, the long neck was a feeding adaptation, and it allowed the Styxosaurus to prey on shoals of fish. Another theory is that the Styxosaurus approached fish from underneath so murky deep waters could mask their bodies to eyes of the prey. Also, to the prey, the Styxosaurus skull and head may have looked like they belonged to a smaller animal, thus hiding the Styxosaurus' deadliness. This made the Styxosaurus efficient stalkers and hunters. The dinosaur's sharp and thin teeth also intermeshed together when the Styxosaurus would close its jaw. The closed tooth jaws would make escape impossible for prey that was caught.

The Styxosaurus is also thought to have had four large fins and a longish tail. It's easy for people to look at a picture of the Styxosaurus and think it was some manner of a sea snake, but most Plesiosaurs were known to have been shaped this way. This Styxosaurus size was smaller than a sperm whale but it was as heavy as a killer whale.

Not unlike other marine dinosaurs and reptiles, there were about 250 gastroliths found within the body of these late Cretaceous Elasmosaurs. There could have been two functions that these gastroliths served for these Elasmosaurs. One was to counter the lift that the air in its lungs provided so that it could swim lower and hunt a variety of fish. Stones found in these Elasmosaurs actually had fish bones on them and it can be surmised that the food was ground by stones for easier digestion. The digestion theory fits perfectly since the Styxosaurus is known to have swallowed its prey whole as the Styxosaurus tooth wasn't meant for cutting. Stones also rubbed scales off of the fish prey. These stones only measured a small fraction of the total Styxosaurus weight. This means that digestion was the primary function, and any added effect of the Styxosaurus sea monster sinking lower to deceive its prey was just a benefit.

How many bones did a Styxosaurus have?

It can't be said for sure how many bones the Styxosaurus skeleton had.

How did they communicate?

Styxosaurus plesiosaurs, being marine, mostly communicated through gestures and motions and possibly chemical cues like pheromones.

How big was a Styxosaurus?

The Styxosaurus plesiosaur was 35-36 ft (10.7-11 m) long. Almost half the Styxosaurus length was its neck, which was 17.2 ft (5.2 m) long. This makes it about 10 times bigger than the Mesosaurus.

Comparing to today's animals, the Styxosaurus was definitely shorter than the sperm whale.

How fast could a Styxosaurus move?

Exact speeds that a Styxosaurus could move at are not known, but it had large fins and was an efficient predator, so it moved quickly.

How much did a Styxosaurus weigh?

Styxosaurus elasmosaurs weighed around 8,000 lb (3,628.7 kg). They were as heavy as today's killer whale.

What were the male and female names of the species?

There are no specific names for the male and female of the Styxosaurus species. The suffix 'saurus' could be applied to the male name, and the suffix 'saura' could be applied to the female name.

What would you call a baby Styxosaurus?

A baby Styxosaurus would be called a juvenile.

What did they eat?

The Styxosaurus primarily ate fish like belemnites, Gillicus, and squid.

The Styxosaurus itself, especially a juvenile, would fall prey to bigger sharks like the Cardabiodon and the Cretoxyrhina. It would face competition for prey from Mosasaurs like the Angolasaurus, the Plioplatecarpus, and the Tylosaurus, which would eventually hunt adult Styxosaurus dinosaurs as well.

How aggressive were they?

The Styxosaurus was a fairly aggressive marine dinosaur, being a carnivore and piscivore. It was an efficient and stealthy hunter. Intraspecific dynamics related to aggression are not known.

Did you know...

The Styxosaurus name has Greek origins. When translated it means 'the Styx lizard', which is a reference to the mythical river Styx. The river Styx was believed to have divided the land of the dead from the land of the living.

The type specimen of the Styxosaurus genus, Styxosaurus browni, was discovered in western Kansas, in Logan County's Hell Creek. The specimen was used by Samuel Paul Welles to describe the genus in the year 1943.

A more complete Styxosaurus fossil specimen was unearthed close to Iona, South Dakota in the year 1945. This specimen of Styxosaurus was named Alzadasaurus pembertoni by Bump and Welles in 1949. But after Bump and Welles, the paleontologist Carpenter brought it under the Styxosaurus genus as the species Stxosaurus snowii.

The Styxosaurus fossil specimen at the School of Mines is mounted with its head in an almost upright position, but this wouldn't have been possible for the species of Styxosaurus plesiosaurs.

The Styxosaurus browni is a new species compared to the older find, Styxosaurus snowii

What are some behavioral adaptations of the Styxosaurus?

One of the interesting facts regarding the Styxosaurus Elasmosaur is that fossil remains discovered in South Dakota had small 250 stones in the belly and stomach. These stones were most probably gastroliths that aided with digestion, much like with other terrestrial and marine dinosaurs. The Styxosaurus did not have teeth adapted to chewing its prey, so the Elasmosaurid dinosaur swallowed it whole. The swallowed fish would be ground up by gastrolith stones. Another possible benefit was that these stones helped these Elasmosaurid Plesiosaurs sink lower so that they could prey on fish that lived deeper, but this was unlikely since these stones constituted only a fraction of the total weight.

Another adaptation could have been using its long neck and small head to appear as a smaller animal that was not threatening to fish. This made hunting easy as the Elasmosaurid dinosaur could hunt from murky areas of the ocean.

What was unique about the Styxosaurus?

The unique thing about the Styxosaurus comes from its Plesiosaur heritage. This dinosaur had a really long neck that made it a dangerous predator since it could attack its prey from below and the prey would never see it coming. The neck of the Styxosaur was almost half its body length. It also had gastroliths or pebbles in its body. These could have served the function of grinding its consumed food or as a tactic to sink lower to hunt various other fish.

Here at Kidadl, we have carefully created lots of interesting family-friendly dinosaur facts for everyone to discover! Learn more about some other dinosaurs from our Rahonavis surprising facts and Chungkingosaurus fun facts for kids pages.

You can even occupy yourself at home by coloring in one of our free printable Styxosaurus coloring pages.

Second image by Johnson Mortimer.