Spinosaurids facts for kids

Quick facts for kids Spinosaurids Temporal range: Late Jurassic–Late Cretaceous, 152–85Ma PreЄ Є O S D C P T J K Pg N
Skeletal reconstruction of Spinosaurus aegyptiacus, National Geographic Museum, Washington, D.C.
Scientific classification
Type species
Spinosaurus aegyptiacus Stromer, 1915
Subgroups
†Suchosaurus †Ostafrikasaurus †Baryonychinae †Baryonyx †Cristatusaurus †Suchomimus †Spinosaurinae †Ichthyovenator †Irritator †Oxalaia †Siamosaurus †Vallibonavenatrix † Spinosaurini †Sigilmassasaurus †Spinosaurus
Synonyms
Baryonychidae Charig & Milner, 1986 Irritatoridae Martill et al., 1996 Sigilmassasauridae Russel, 1996

Spinosauridae (say: Spine-oh-SAWR-ih-dee) means 'spined lizards'. This is a group of meat-eating theropod dinosaurs. They lived during the Jurassic and Cretaceous periods. What makes them special is their lifestyle. Unlike most meat-eating dinosaurs, spinosaurids spent a lot of time near water. Their diet was mostly fish.

Fossils of spinosaurids have been found all over the world. This includes places like Asia, South America, Europe, Africa, and Australia.

What Did Spinosaurids Look Like?

Size comparison of different spinosaurids with a human

Spinosaurids had longer arms than most other theropods. Their first finger often had the biggest claw. They had jaws that looked a lot like those of crocodiles. Their teeth were long and shaped like cones. These teeth were perfect for catching and holding onto prey, especially slippery fish.

Because they trapped their food, their teeth usually did not have sharp, knife-like edges. Many other meat-eating dinosaurs had these sharp edges, called serrations, to tear meat.

The most famous member of this family is Spinosaurus. It was the first spinosaurid ever found. It is also the largest meat-eating dinosaur we know of! Scientists think Spinosaurus could grow up to 15 meters (49 feet) long. That's as long as a school bus!

How Spinosaurids Lived

In 2010, a study by Roman Amiot and his team found something amazing. Spinosaurids lived a semi-aquatic life. This means they spent time both in water and on land. They lived in places similar to where hippopotamuses, crocodiles, and turtles live today. This made them very unusual among other theropods.

This watery lifestyle also helped them avoid fighting with other big predators for food. For example, Carcharodontosaurus lived at the same time as Sigilmassasaurus and Spinosaurus. But they didn't compete for food. The spinosaurids ate fish. Carcharodontosaurus mostly hunted smaller dinosaurs on land.

How Spinosaurids Are Grouped

The family "Spinosauridae" was named by a German paleontologist named Ernst Stromer. He named them in 1915. Stromer was the one who discovered the first dinosaur in this group, Spinosaurus.

As scientists found more fossils of its close relatives, the family was divided. It was split into two smaller groups, called subfamilies: Baryonychinae and Spinosaurinae. This split was made because of differences in their skulls and teeth.

Spinosaurus aegyptiacus, the largest meat-eating dinosaur

Skeletons of Suchomimus and Baryonyx

Scientists use something called a cladogram to show how different dinosaurs are related. Here is a simplified cladogram from 2017. It shows how spinosaurids fit within a larger group called Megalosauroidea.

Images for kids

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  Parts of the first Spinosaurus aegyptiacus fossil, drawn by Ernst Stromer in 1915

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  A close-up of Suchomimus teeth

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  Reconstructed back sails of four spinosaurids: Spinosaurus, Irritator, Ichthyovenator, and Suchomimus.

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  A diagram showing the sizes of different spinosaurids

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  Comparing a spinosaurid skull with that of Dubreuillosaurus and two modern pike conger eels

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  An artist's idea of Baryonyx with a fish in its mouth

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  An artist's idea of the head of Spinosaurus

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  A reconstructed Irritator skeleton attacking a pterosaur at the National Museum of Rio de Janeiro

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  A reconstructed front leg and hand of Suchomimus at the Museum of Ancient Life in Utah

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  The first skull fossils of Irritator challengeri (top) and Angaturama limai (bottom)

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  An artist's idea of Spinosaurus swimming with other water animals from the Kem Kem Beds

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  Maps showing where spinosaurid fossils were found over different time periods

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  A possible Australian spinosaurid neck bone from different angles, compared to Baryonyx

See also

In Spanish: Espinosáuridos para niños