Open Paleo

Seitaad

Sertich & Loewen, 2010 SAY-eet-AWD

From Navajo 'seit'aad', a sand-swallowing monster from Navajo mythology, referring to the specimen being preserved entombed in the Navajo Sandstone.

192.9–174.7 million years ago Pliensbachian–Toarcian, Early Jurassic
Early Jurassic stages

Seitaad is a genus of sauropodomorph dinosaur which lived during the Early Jurassic period in what is now southern Utah, United States.

Under dispute

Seitaad ruessi is recovered outside Massospondylidae among basal Sauropodiformes by Apaldetti and colleagues (2011) but within Massospondylidae by Rauhut and colleagues (2020).

Diagnosis

  1. Plate-like medial process of the scapula contributing posteriorly to glenoid surface
  2. Prominent deltopectoral crest offset proximally from head of humerus by distinct proximally directed hook
  3. Proximally convex and laterally expanded proximal surface of metacarpal I
  4. Mid-dorsal neural arches subequal to or taller than respective centra
  5. Pubis with transversely narrow and elongate apron and relatively small obturator foramen
  6. Enlarged pedal ungual present on digit II

Species

Seitaad ruessi Sertich & Loewen, 2010

Type species

Named for Everett Ruess, a young artist, poet, and naturalist who mysteriously disappeared in 1934 while exploring southern Utah near where the holotype was found.

Holotype
UMNH VP 18040 , Utah Museum of Natural History
Material
Articulated partial postcranial skeleton including portions of 11 dorsal vertebrae, 16 dorsal ribs, both pectoral girdles, nearly complete left and partial right forelimb, partial pelvis, and partial left hind limb
Horizon
lower Navajo Sandstone Formation, Pliensbachian–Toarcian, Early Jurassic , 192.9–174.7 million years ago
Locality
UMNH VP Locality 191, Utah, United States

References

  1. Sertich, J. J. W.; Loewen, M. A. (2010). A New Basal Sauropodomorph Dinosaur from the Lower Jurassic Navajo Sandstone of Southern Utah. PLoS ONE 5(3): e9789. Public Library of Science (PLoS). doi:10.1371/journal.pone.0009789 sertich2010a
  2. Paul, G. S. (2024). The Princeton Field Guide to Dinosaurs (3rd ed.). Princeton University Press.

    Source of the body length and mass estimates.

    paul2024a
  3. Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Sauropods. Princeton University Press.

    Source of the hip height estimate.

    jones2026b
  4. Apaldetti, C.; Martínez, R. N.; Alcober, O. A.; Pol, D. (2011). A New Basal Sauropodomorph (Dinosauria: Saurischia) from Quebrada del Barro Formation (Marayes-El Carrizal Basin), Northwestern Argentina. PLoS ONE 6(11): e26964. Public Library of Science (PLoS). doi:10.1371/journal.pone.0026964

    Recovered Seitaad outside Massospondylidae, among basal Sauropodiformes.

    apaldetti2011a
  5. Rauhut, O. W. M.; Holwerda, F. M.; Furrer, H. (2020). A derived sauropodiform dinosaur and other sauropodomorph material from the Late Triassic of Canton Schaffhausen, Switzerland. Swiss Journal of Geosciences 113(1). Pensoft Publishers. doi:10.1186/s00015-020-00360-8

    Recovered Seitaad within Massospondylidae.

    rauhut2020a