Fun Xiphactinus Facts For Kids

Xiphactinus (Xiphactinus audax) means ‘sword ray’ in Greek and belonged to the phylum Chordata, class Actinopterygii, order Chthyodectiformes, and subfamily Chthyodectinae. They were large bony fishes but were no less than sea monsters. They were 15-20 ft (4.57-6.09 m) long and used to inhabit the areas of the western interior sea which is present-day North America and they lived during the Late Cretaceous period. Their body features and appearances resembled a lot to the Gargantuan, which was a fanged tarpon. The junior synonym of the species is Portheus molossus Cope. Like many other sauropods and theropods, there was a moment with the name of this giant fish as well. In the 1870s, there was confusion about whether the name of this fish was actually correct or not. Their teeth were very sharp to catch their prey easily. Then finally in 1870, a scientist named Joseph Leidy gave the name Xiphactinus to this fish from a 16 in (40.64 cm) long fragment of a pectoral fin which was collected by  Dr. George M. Sternberg. Just one year before that, E. D. Cope gave the name Portheus molossus to the many specimens discover near Fort Wallace. Joseph Leidy was the first one to name them and hence his given name is prevalent today, but the name given by E. D. Cope is more popular and is widely in use.

For more interesting facts, keep reading. And don't forget to check out more interesting facts about other dinosaurs like the Cretoxyrhina and Simolestes.

Was the Xiphactinus a dinosaur?

No, the Xiphactinus was not a dinosaur. Rather it was a large ferocious fish that was almost like a monster of the sea.

How do you pronounce 'Xiphactinus'?

The pronunciation of this predatory bony fish is 'Zif-ack-tih-nus'. This fish is among those fishes who inhabited the Pierre Sea.

What type of prehistoric animal was a Xiphactinus?

Xiphactinus was a giant predatory fish of the subfamily Chthyodectinae. These animals used to grab prey smaller than them with their big, terrifying jaws and thrash them fiercely to reduce their energy.

In which geological period did the Xiphactinus live?

The Xiphactinus used to live in the late cretaceous period (Albian to Maastrichtian), which was somewhere between 85-65 million years ago.  The name Xiphactinus refers to the 'sword ray'. They were existing in the countries of North America, Europe, and Australia.

When did the Xiphactinus become extinct?

The exact account of their extinction is not clear yet. They went extinct around 70-80 million years ago, during or after the Cretaceous period.

Where did a Xiphactinus live?

They were aquatic animals and many specimens and fossils were recovered from Australia, North America, and Europe. One of the first fossils was discovered in the 1850s in the Niobrara Chalk. Joseph Leidy was the first one to name them. Though they were considered to be endemic to North America, they were said to be found in Europe too.

What was a Xiphactinus' habitat?

Although they are aquatic animals, unlike other fishes who prefer deep water, they used to live in shallow waters. The fossil was found in Kansas.

Who did a Xiphactinus live with?

These fishes were very much active socially and always used to travel in medium-sized packs or shoals. They used to spend most of their time simply cruising around on the surface waters to hunt fish. Just like modern-day dolphins, they also had the ability to jump clear of the water. They used to do that to remove the loose scales from the body or any other parasites attached to their body.

How long did a Xiphactinus live?

The lifespan of Xiphactinus is not known yet after the study of the fossil. They used to inhabit the areas of the western interior sea which is present-day North America and they lived during the Late Cretaceous period.

How did they reproduce?

They were egg-laying animals and used to lay a clutch of at least 10-12 eggs. The fossil was recovered from Kansas.

What did a Xiphactinus look like?

Xiphactinus was a colorful bony fish in the marine world and had a large torpedo-like long body and multiple rows of its long razor-sharp teeth. They resemble a lot to a large barracuda but had a relatively shorter head like a piranha. They have an abyssal variant that used to have two lures that emitted light and a bioluminescent patterning. They were around 15-20 ft (4.57 - 6.09 m) long and had a weight of 1-2 tons (907.18-1814.37 kg). Their fossil was recovered from Kansas. Their lower jaw was hinged and helped them to open their mouth wide enough for large prey. They were considered ugly fishes and that’s why they got the name ‘bulldog fishes’. Their bodies were streamlined and they had muscular tails.

How many bones did a Xiphactinus have?

Xiphactinus used to have 85 vertebrae according to Bardack. Joseph Leidy was the first one to name them. They shark-like teeth and the fossil was found in Kansas. The total number of bones they had is unknown.

How did they communicate?

They used to communicate by making sounds. They were able to catch injured prey easily.

How big was a Xiphactinus?

These famous giant marine predators of Australia were 15-20 ft (4.57-6.09 m). They were like giant monsters of the marine world. The Xiphactinus was twice as tall as humans today and might be able to eat them whole in one go.

How fast could a Xiphactinus swim?

Because of the streamlined body of this bony fish Xiphactinus species (X audax), and a supporting tail, these species were able to attain a swimming speed of 37.28 mph (60 kph). This speed was one of the added advantages of their hunting behavior. With this speed, they were able to catch almost any prey they wanted.

How much did a Xiphactinus weigh?

This shark-like fish of cretaceous period Xiphactinus (X audax) size or weight was almost 1-2 tons (907.18-1814.37 kg). Joseph Leidy named them first and the fossil was found in Kansas.

What were the male and female names of the species?

There are no specific names for the male and the female of this dinosaur species of Europe Xiphactinus (Xiphactinus audax).

What would you call a baby Xiphactinus?

The baby of this dinosaur species Xiphactinus (Xiphactinus audax) does not have any particular name to get called by. They were simply called baby Xiphactinus.

What did they eat?

Xiphactinus was a vulnerable fish to attack the injured prey, but giant predators like Tylosaurus could have easily killed it. Although they were very dangerous but were not the top one as it was itself prey to another giant species called Mosasaurs that used to live in the same time. It is believed that they might have overpowered Mosasaurs when they used to hunt them in small shoals.

How aggressive were they?

They were one of the most giant fishes and creatures ever-present on earth. They were very much like piranhas and had scary mouths. A long fragment of a pectoral fin was collected by  Dr. George M. Sternberg.

Did you know...

These famous sword ray fishes were the same as the length of these great white sharks today.

Where are Xiphactinus fossils found?

The fossils of this Xiphactinus fish have been found in the Carlile Shale and Greenhorn Limestone of Kansas and some Cretaceous formations along the East Coast, mainly North Carolina, Alabama, Georgia, and New Jersey.

How long ago did Xiphactinus live?

Xiphactinus got extinct tens of millions of years ago from now.

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 Muzquizopteryx facts pages and Macroplata facts pages.

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