Stegosauria

The Stegosaurs were a group of dinosaurs in the suborder Thyreophora. They have small heads, peg-like teeth and vertical bony plates and spines on their back and tail. They flourished from the Upper Jurassic to the Lower Cretaceous.

Stegosauria Temporal range: Middle Jurassic – Lower Cretaceous, 169–100 mya
Fossil skeleton of a Stegosaurus, National Museum of Natural History
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Sauropsida
Superorder:	Dinosauria
Order:	Ornithischia
Suborder:	Thyreophora
Infraorder:	Stegosauria

File:FieldMuseum5 Chicago.jpg

A fossil melée involving a stegosaurian (Tuojiangosaurus) and a mid-sized theropod (Monolophosaurus), Field Museum in Chicago

Classification

The Stegosauria was originally named as an order by O.C. Marsh in 1877. Now it is treated as an infraorder or suborder (or simply a clade) within the armoured dinosaurs, the Thyreophora. The Stegosauria includes the families Huayangosauridae and Stegosauridae.

The Huayangosauridae were an early family of stegosaurs from the Middle Jurassic. They were smaller than later stegosaurs and had shorter and higher skulls. The type genus is Huayangosaurus of China. The poorly-known remains of Regnosaurus from England suggest it also could be a member. Its lower jaw is very similar to that of the former.

The vast majority of stegosaurs being in the Stegosauridae. They lived in the later part of the Jurassic and the early Cretaceous. The group includes the well-known Stegosaurus. The family is widespread, with fossils found in the Northern Hemisphere and Africa. Their decline coincides with that of the Cycadophyta.

Suborder Thyreophora

Infraorder Stegosauria

• Family Huayangosauridae
  • Huayangosaurus (Sichuan, China)
  • ?Regnosaurus (Sussex, England)
• Family Stegosauridae
  • Adratiklit – (Morocco)
  • Chialingosaurus – (Sichuan, China)
  • Chungkingosaurus – (Chongqing, China)
  • Dacentrurus – (England, France & Spain)
  • Hesperosaurus – (Wyoming, USA)
  • Miragaia – (Portugal)
  • Monkonosaurus – (Tibet, China)
  • Paranthodon – (South Africa)
  • Wuerhosaurus – (Xinjiang, Western China)
  • Kentrosaurus – (Tanzania, Africa)
  • Lexovisaurus – (England & France)
  • Stegosaurus – (Wyoming, USA)
  • Tuojiangosaurus – (Sichuan, China)
  • ?Craterosaurus – (Bedfordshire, England)
  • Jiangjunosaurus – (Xinjiang, Western China)

• Uncertain placement (incertae sedis)
  • Gigantspinosaurus – (Sichuan, China)

Stegosauria Media

• Position of bones in skeleton sketched by Arthur Lakes.jpg

  Stegosaurus bones illustrated by Arthur Lakes in 1879

• Stegosaurus ungulatus model Lull 1910.png

  An early life restoration of a Stegosaurus from 1910

• DMSN dinosaurs.jpg

  Stegosaurus mount showing to a good effect the high neck posture, the throat ossicles and the robust shoulder girdle and forelimbs

• Stegosauridae Trinity.jpg

  Illustration comparing three stegosaurids by Danny Cicchetti, 2013.

• Ankylosaurus magniventris by sphenaphinae.png

  Ankylosaurus magniventris by sphenaphinae

• Isaberrysaura mollensis.png

  Speculative life reconstruction of Isaberrysaura mollensis as a traditional stegosaurian

• Bashanosaurus primitivus.png

  Life reconstruction of Bashanosaurus primitivus

• 

  Life reconstruction of Huayangosaurus taibaii

• Baiyinosaurus baojiensis.png

  Life reconstruction of Baiyinosaurus baojiensis.

• Gigantspinosaurus sichuanensis.png

  Gigantspinosaurus sichuanensis