Smitanosaurus
Meaning 'smith lizard' (from Old Saxon 'smitan'), referring to J. August Smith, who excavated and sketched the holotype USNM 5384, and to the Smithsonian Institution where the remains are stored.
Late Jurassic stages
Smitanosaurus is a genus of dicraeosaurid sauropod dinosaur from the Late Jurassic of Colorado. The genus contains one species, S. agilis, originally assigned to the defunct genus Morosaurus.
Diagnosis
- Atlas lacking the 'lip' on the anteroventral margin (interpreted as a reversal)
- Axial neural spine both tall and subvertically oriented
- Axis with postzygapophyseal articular surfaces facing ventrally rather than posteroventrally
- Small but conspicuous posteriorly projecting spur on the squamosal
- Supratemporal fenestrae narrower than the maximum height of foramen magnum
- Sharp-lipped pneumatic fossa on the lateral surface of the axial intercentrum
Species
Smitanosaurus agilis Whitlock & Wilson Mantilla, 2020
Type species
From Latin 'agilis' meaning 'agile' or 'nimble'.
- Holotype
- USNM 5384 , National Museum of Natural History, Smithsonian Institution
- Material
- Braincase, partial skull roof, proatlases, and first three cervical vertebrae
- Horizon
- Morrison Formation, Kimmeridgian–Tithonian, Late Jurassic , 154.8–143.1 million years ago
- Locality
- Felch Quarry 1, Garden Park, Colorado, United States
References
- Whitlock, J. A.; Wilson Mantilla, J. A. (2020). The Late Jurassic sauropod dinosaur 'Morosaurus' agilis Marsh, 1889 reexamined and reinterpreted as a dicraeosaurid. Journal of Vertebrate Paleontology 40(6): e1780600. Informa UK Limited. doi:10.1080/02724634.2020.1780600 whitlock2020a
-
Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Sauropods. Princeton University Press.
Source of the body length, mass, and hip height estimates.
jones2026b