Open Paleo

Erketu

Ksepka & Norell, 2006 er-kee-tu

Named after Erketü Tengri, a deity in Mongolian mythology, honoring the region where the dinosaur was found.

100.5–83.6 million years ago Cenomanian–Santonian, Late Cretaceous
Late Cretaceous stages

Erketu is a genus of somphospondylan dinosaur that lived in Asia during the Late Cretaceous, roughly between 96 million and 89 million years ago. It is known from the Bayanshiree Formation of Mongolia, and its fossils were found between 2002 and 2003 during field expeditions. Erketu was first described in 2006 and later on in 2010 due to some cervicals that were left behind in the expedition. This genus represents the first sauropod described from the Bayanshiree Formation. The elongated cervical vertebrae indicate that it probably had the longest neck relative to its body size of any sauropod.

Diagnosis

  1. Extremely elongated anterior cervical centra with elongation index exceeding 5.0, unique among Titanosauriformes with known cervical vertebrae.
  2. Bifurcate (bifid) neural spines on fourth and succeeding cervical vertebrae with very low, thickened metapophyses bearing a small anterior tubercle.
  3. Crescent-shaped (strongly concave lateral border) sternal plate.
  4. Hypertrophied prezygodiapophyseal lamina in cervicals 4-5, extending far anterior of the articular facet as a thin plate perpendicular to the articular plane.
  5. Cervical centra significantly taller than wide at the cotyle in postaxial vertebrae.

Species

Erketu ellisoni Ksepka & Norell, 2006

Type species

Named for Mick Ellison, senior principal paleoartist at the American Museum of Natural History and close friend of describer Mark Norell.

Holotype
IGM 100/1803 , Paleontological Center, Mongolian Academy of Sciences
Material
Articulated cervical series including complete first through fifth cervical vertebrae, partial sixth cervical vertebra, right sternal plate, articulated right tibia, fibula, astragalus, and calcaneum.
Horizon
Bayanshiree Formation, Cenomanian–Santonian, Late Cretaceous , 100.5–83.6 million years ago The age of the containing rock unit; no finer age has been published.
Locality
Bor Guvé, Dornogovi, Mongolia

References

  1. Ksepka, D. T.; Norell, M. A. (2006). Erketu Ellisoni, a Long-necked Sauropod from Bor Guvé (Dornogov Aimag, Mongolia). American Museum Novitates 3508(1). American Museum of Natural History (BioOne sponsored). doi:10.1206/0003-0082(2006)3508[1:eealsf]2.0.co;2 ksepka2006a
  2. Ksepka, D. T.; Norell, M. A. (2010). The illusory evidence for Asian Brachiosauridae: new material of Erketu ellisoni and a phylogenetic reappraisal of basal Titanosauriformes. American Museum Novitates 3700: 1-27. American Museum of Natural History. doi:10.1206/3700.2

    Refers the Bor Guve deposits to the Bayanshiree Formation and retracts the erecting paper's Early Cretaceous age, making the fossils early Late Cretaceous.

    ksepka2010a
  3. Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Sauropods. Princeton University Press.

    Source of the hip height estimate, and the appearance features.

    jones2026b