Open Paleo

Epachthosaurus

Powell, 1990 e-PAK-tho-SAWR-us

From Greek epachthes (heavy/burdensome) + sauros (lizard): 'heavy lizard', likely referring to its robust build as a large titanosaur.

100.5–89.8 million years ago Cenomanian–Turonian, Late Cretaceous
Late Cretaceous stages

Epachthosaurus was a genus of titanosaurian sauropod dinosaur, belonging to Lithostrotia, from the Late Cretaceous of Central and Northern Patagonia in South America.

Diagnosis

  1. Dorsal vertebrae with relatively large, wide, and depressed centra
  2. Pleurocoels wider and deeper than those in other known titanosaurs, eye-shaped
  3. Posterior dorsal neural spines compressed anteroposteriorly with a wide and well-developed prespinal lamina
  4. Prespinal lamina bifurcated at its base, forming spinoprezygapophyseal laminae
  5. Diapophysis without dorsal flattening distally

Species

Epachthosaurus sciuttoi Powell, 1990

Type species

Named in honor of Dr. J. C. Sciutto, who reported the dinosaurian locality at the Ocho Hermanos Ranch where the holotype material was found.

Holotype
MACN-CH 1317 , Museo Argentino de Ciencias Naturales ‘Bernardino Rivadavia’
Material
Incomplete posterior dorsal vertebra
Horizon
lower Bajo Barreal Formation, Cenomanian–Turonian, Late Cretaceous , 100.5–89.8 million years ago
Locality
Estancia Ocho Hermanos, Chubut, Argentina

Notable specimens

  • UNPSJB-PV 920

    Universidad Nacional de la Patagonia San Juan Bosco most complete

    A nearly complete, well-preserved, articulated referred skeleton and one of the most complete titanosaurian skeletons known, missing only the skull, neck, four or five cranial dorsal vertebrae, and several distal caudals.

    Martínez et al. (2004)

References

  1. Powell, J. E. (1990). Epachthosaurus sciuttoi (gen. et sp. nov.), un dinosaurio sauropodo del Cretácico de Patagonia (Provincia de Chubut, Argentina) [Epachthosaurus sciuttoi (gen. et sp. nov.), a sauropod dinosaur from the Cretaceous of Patagonia (Chubut province, Argentina)]. Actas del V Congreso Argentino de Paleontologia y Bioestratigrafia, Tucumán, Argentina 1: 123-128. powell1990a
  2. Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Sauropods. Princeton University Press.

    Source of the body length, mass, and hip height estimates.

    jones2026b
  3. Martínez, R. D.; Giménez, O.; Rodríguez, J.; Luna, M.; Lamanna, M. C. (2004). An articulated specimen of the basal titanosaurian (Dinosauria: Sauropoda) Epachthosaurus sciuttoi from the early Late Cretaceous Bajo Barreal Formation of Chubut Province, Argentina. Journal of Vertebrate Paleontology 24(1): 107-120. doi:10.1671/9.1

    Revises the holotype's horizon to the lower part of the Bajo Barreal Formation.

    martínez2004a