Open Paleo

Stegosauridae

Marsh, 1880 Type genus Stegosaurus

Its genera lived 170.9–100.5 million years ago Middle Jurassic–Early Cretaceous

Stegosauridae is a family of plated, quadrupedal stegosaurian dinosaurs that accounts for the vast majority of known stegosaurian diversity. Its members lived from the later part of the Jurassic into the Early Cretaceous and ranged widely, with fossils found across the Northern Hemisphere as well as Africa and South America. Stegosaurids are set apart from more basal stegosaurians by the loss of the premaxillary teeth and of the lateral rows of bony scutes along the trunk, together with long, narrow skulls and hindlimbs markedly longer than the forelimbs. The most derived forms carry very large, thin dorsal plates arranged in two staggered parasagittal rows, along with paired spikes at the end of the tail. The family is conventionally divided into two subfamilies, the long-spined Dacentrurinae and the plate-bearing Stegosaurinae, which together make up the clade Neostegosauria; several basal and fragmentary members fall outside this split.

Diagnosis

  1. Elongated nasal process of the premaxilla forming the anterodorsal margin of the external naris
  2. Fourth trochanter of the femur extremely reduced or absent
  3. Absence of ossified epaxial tendons
  4. Transversely enlarged summits on the proximal caudal neural spines

Clades within Stegosauridae

Genera placed directly in Stegosauridae

  • Alcovasaurus Galton & Carpenter, 2016 Kimmeridgian–Tithonian (154.8–143.1 Ma)United Statesincertae sedis
  • Kentrosaurus Hennig, 1915 Kimmeridgian–Tithonian (154.8–143.1 Ma)Tanzaniaunder dispute
  • Lexovisaurus Nomen dubium Hoffstetter, 1957 Callovian (165.3–161.5 Ma)United Kingdomincertae sedis
  • Miragaia Disputed Mateus et al., 2009 Kimmeridgian–Tithonian (154.8–143.1 Ma)Portugal
  • Paranthodon Nopcsa, 1929 Berriasian–Valanginian (143.1–132.6 Ma)South Africa
  • Tuojiangosaurus Dong et al., 1977 Bajocian–Oxfordian (170.9–154.8 Ma)China

References

  1. Marsh, O. C. (1880). Principal characters of American Jurassic dinosaurs, Part III. American Journal of Science s3-19(111): 253-259. doi:10.2475/ajs.s3-19.111.253

    Introduced the name Stegosauridae in passing, suggesting that Stegosaurus and Omosaurus might belong to the same family.

    marsh1880a
  2. Madzia, D.; Arbour, V. M.; Boyd, C. A.; Farke, A. A.; Cruzado-Caballero, P.; Evans, D. C. (2021). The phylogenetic nomenclature of ornithischian dinosaurs. PeerJ 9: e12362. doi:10.7717/peerj.12362

    Defined Stegosauridae as the largest clade containing Stegosaurus stenops but not Huayangosaurus taibaii.

    madzia2021a
  3. Sánchez-Fenollosa, S.; Cobos, A. (2025). New insights into the phylogeny and skull evolution of stegosaurian dinosaurs: an extraordinary cranium from the European Late Jurassic (Dinosauria: Stegosauria). Vertebrate Zoology 75: 165-189. doi:10.3897/vz.75.e146618

    Revised stegosaurian phylogeny, applying Madzia and colleagues' definition of Stegosauridae.

    sánchez-fenollosa2025a