Safekipedia

Thyreophora

Adapted from Wikipedia ยท Discoverer experience

A skeletal reconstruction of Edmontonia, an armored dinosaur from the Late Cretaceous period.

Thyreophora, often called armored dinosaurs, is a group of armored ornithischian dinosaurs that lived from the Early Jurassic until the end of the Cretaceous. These dinosaurs are special because they had body armor along their bodies. Early ones had simple, flat plates, while later ones had more complex shapes like spikes and big plates.

Most of these dinosaurs ate plants and had smaller brains compared to their body size. Thyreophora includes two main groups: Ankylosauria and Stegosauria. In both groups, the front legs were shorter than the back legs, especially in stegosaurs. These dinosaurs are defined as all species more closely related to Ankylosaurus and Stegosaurus than to Iguanodon and Triceratops. They are considered a close relative of Cerapoda within Genasauria.

Characteristics

Thyreophorans, a group of armored dinosaurs, had special bony growths in their skin called osteoderms. These bony growths often had ridges along their sides. They also had unique features in their skulls and jaws, such as a wide cheekbone and a special shape to their teeth. Some early thyreophorans, like Scutellosaurus, might have walked mostly on two legs, while others, like Scelidosaurus, likely used four legs most of the time. Later groups, such as stegosaurs and ankylosaurs, are believed to have always walked on four legs.

Classification

Thyreophora, often called armored dinosaurs, includes two main groups: Stegosauria and Ankylosauria. Scientists sometimes use different ways to group these dinosaurs, but they all agree that Thyreophora is a big group that includes both stegosaurs and ankylosaurs.

Thyreophora was first named in 1915. In 1998, a scientist named Paul Sereno defined it as all dinosaurs more closely related to Ankylosaurus than to Triceratops. In 2021, researchers made the definitions of these groups more official to help everyone agree on how to classify them. These groups help scientists understand how these dinosaurs are related to each other.

Images

Skeleton of Saichania, an armored dinosaur from the time of the dinosaurs, displayed in a museum in Japan.
Map showing where armored dinosaurs like Stegosaurus lived during prehistoric times.
Scientific illustration of Lesothosaurus diagnosticus, an early dinosaur, shown for educational purposes.
Illustration of Emausaurus, an armored dinosaur from the time of the dinosaurs, showing its bony plates for protection.
An artistic reconstruction of Scelidosaurus, an armored dinosaur from the Jurassic period, showing its bony plates and quadrupedal stance.
Illustration of Yuxisaurus, an early armored dinosaur from the Jurassic period, showing its heavy build and spiked defense.
Illustration of Jakapil, an ancient dinosaur from Argentina, showing its unique features like a bipedal stance and tough plant-eating teeth.
An artistic reconstruction of a Stegosaurus, a large armored dinosaur from the Late Jurassic period known for its distinctive plates on its back and spikes on its tail.
Illustration of Stegouros, a small armored dinosaur with unique axe-like spikes on its tail.
An artistic reconstruction of Ankylosaurus, a heavily armored dinosaur from the Late Cretaceous period, showing its clubbed tail and protective body armor.
A scientific illustration of Laquintasaura venezuelae, an early Jurassic dinosaur, shown in its natural habitat.
A scientific illustration of Heterodontosaurus, an early dinosaur from the Jurassic period, showing its features based on fossil evidence.

Related articles

Dinosaur
Jurassic
Cretaceous
Stegosauria
Ankylosaurus
Stegosaurus

This article is a child-friendly adaptation of the Wikipedia article on Thyreophora, available under CC BY-SA 4.0.

Images from Wikimedia Commons. Tap any image to view credits and license.