Open Paleo

Isisaurus

Jain & Bandyopadhyay, 1997 iss-ee-sore-us

Named after the Indian Statistical Institute (ISI), combined with Greek sauros (lizard); meaning 'ISI lizard'

72.2–66.0 million years ago Maastrichtian, Late Cretaceous
Late Cretaceous stages

Isisaurus is a genus of titanosaurian dinosaur from the Late Cretaceous Lameta Formation of India and Pab Formation of Pakistan. The genus contains a single species, Isisaurus colberti.

Diagnosis

  1. Anteroposteriorly elongate cervical parapophyses
  2. Cervical neural arches with prespinal and postspinal laminae
  3. Anteriormost dorsal vertebra with pronounced coel between prezygodiapophyseal, centroprezygapophyseal and anterior centrodiapophyseal laminae
  4. Posterior dorsal neural arches with parapophyses positioned above the level of the prezygapophyses
  5. Anteroposteriorly compressed distal caudal chevron blades

Species

Isisaurus colberti Jain & Bandyopadhyay, 1997

Type species

Named for Edwin Harris Colbert, the American vertebrate paleontologist.

Holotype
ISIR 335/1, ISIR 335/2, ISIR 335/3, ISIR 335/4, ISIR 335/5, ISIR 335/6, ISIR 335/7, ISIR 335/8, ISIR 335/9, ISIR 335/10, ISIR 335/11, ISIR 335/12, ISIR 335/13, ISIR 335/14, ISIR 335/15, ISIR 335/16, ISIR 335/17, ISIR 335/18, ISIR 335/19, ISIR 335/20, ISIR 335/21, ISIR 335/22, ISIR 335/23, ISIR 335/24, ISIR 335/25, ISIR 335/26, ISIR 335/27, ISIR 335/28, ISIR 335/29, ISIR 335/30, ISIR 335/31, ISIR 335/32, ISIR 335/33, ISIR 335/34, ISIR 335/35, ISIR 335/36, ISIR 335/37, ISIR 335/38, ISIR 335/39, ISIR 335/40, ISIR 335/41, ISIR 335/42, ISIR 335/43, ISIR 335/44, ISIR 335/45, ISIR 335/46, ISIR 335/47, ISIR 335/48, ISIR 335/49, ISIR 335/50, ISIR 335/51, ISIR 335/52, ISIR 335/53, ISIR 335/54, ISIR 335/55, ISIR 335/56, ISIR 335/57, ISIR 335/58, ISIR 335/59, ISIR 335/60, ISIR 335/61, ISIR 335/62, ISIR 335/63, ISIR 335/64, ISIR 335/65 , Geology Museum, Indian Statistical Institute
Material
Partial skeleton of a single individual: partial axial column, shoulder and pelvic girdles, and a forelimb lacking the radius and manus.
Horizon
Lameta Formation, Maastrichtian, Late Cretaceous , 72.2–66.0 million years ago
Locality
Dongargaon village, Maharashtra, India

Synonyms

  • Titanosaurus colberti reassigned

    The species was erected as Titanosaurus colberti by Jain and Bandyopadhyay (1997); Wilson and Upchurch (2003) found Titanosaurus indicus undiagnostic and moved the species to the new genus Isisaurus.

References

  1. Jain, S. L.; Bandyopadhyay, S. (1997). New titanosaurid (Dinosauria: Sauropoda) from the Late Cretaceous of central India. Journal of Vertebrate Paleontology 17(1): 114-136. Informa UK Limited. doi:10.1080/02724634.1997.10010958

    Erects the species as Titanosaurus colberti on the Dongargaon skeleton, giving the holotype as ISIR335/1-65.

    jain1997a
  2. Wilson, J. A.; Upchurch, P. (2003). A revision of Titanosaurus Lydekker (Dinosauria - Sauropoda), the first dinosaur genus with a 'Gondwanan' distribution. Journal of Systematic Palaeontology 1(3): 125-160. Informa UK Limited. doi:10.1017/S1477201903001044 wilson2003b
  3. Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Sauropods. Princeton University Press.

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

    jones2026b