Open Paleo

Volgatitan

Averianov & Efimov, 2018 VOL-guh-TIE-tan

Named for the Volga River region of Russia (Ulyanovsk Oblast) where the fossils were found, combined with 'titan' meaning 'giant'.

132.6–125.8 million years ago Hauterivian, Early Cretaceous
Early Cretaceous stages

Volgatitan is a genus of titanosaurian sauropod dinosaur from the Early Cretaceous of the Ulyanovsk Oblast, Russia. The type and only species is Volgatitan simbirskiensis, known from seven caudal vertebrae from a single individual. It is the oldest known titanosaur from the northern hemisphere, and is considered important for being related to the Lognkosauria, a group known only from South America later in the Late Cretaceous. It was first described in November 2018 by Russian paleontologists Alexander Averianov and Vladimir Efimov. It is estimated to have weighed about 17.3 metric tons (19.1 short tons).

Diagnosis

  1. Deeply procoelous anterior caudal centra with distinctly concave anterior articular surface and strongly convex ball-like posterior articular surface
  2. Procoelous middle caudal centra with same degree of procoelity as anterior caudals
  3. Long anterior caudal centra with centrum length to anterior centrum height ratio of 0.98
  4. Prominent ventral ridge on anterior and middle caudal centra
  5. Neural arch confined to anterior half of centrum in anterior and middle caudals
  6. Hyposphene-hypantrum articulation present in anterior caudal vertebrae
  7. Somphospondylous (camellate) bone texture in caudal vertebrae

Species

Volgatitan simbirskiensis Averianov & Efimov, 2018

Type species

Named for Simbirsk, the historical name of Ulyanovsk Oblast, Russia, where the fossils were found, with the suffix '-ensis' meaning 'from'.

Holotype
UPM 976/1−7 , Udory Paleontological Museum
Material
Seven caudal vertebrae from a single individual.
Horizon
Hauterivian, Early Cretaceous , 132.6–125.8 million years ago
Locality
Slantsevy Rudnik, Ulyanovsk, Russia Averianov and Efimov (2018) place the holotype by ammonite biozone rather than by rock unit, in the Speetoniceras versicolor Zone of the upper Hauterivian; the shales at Slantsevy Rudnik carry no formation name, and both Bandeira and colleagues (2024) and Mannion and colleagues (2026) still describe the unit as unnamed.

References

  1. Averianov, A.; Efimov, V. (2018). The oldest titanosaurian sauropod of the Northern Hemisphere. Biological Communications 63(3): 145-162. Saint Petersburg State University. doi:10.21638/spbu03.2018.301 averianov2018b
  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. Bandeira, K. L. N.; Navarro, B. A.; Pêgas, R. V.; Brilhante, N. S.; Brum, A. S.; de Souza, L. G.; da Silva, R. C.; Gallo, V. (2024). A reassessment of the historical fossil findings from Bahia State (Northeast Brazil) reveals a diversified dinosaur fauna in the Lower Cretaceous of South America. Historical Biology 37(3): 548-589. Informa UK Limited. doi:10.1080/08912963.2024.2318406 bandeira2024a
  4. Mannion, P. D.; Carvalho, I. S. (2026). Re-evaluation of the Early Cretaceous titanosauriform sauropod dinosaur Triunfosaurus leonardii from the Triunfo Basin, Brazil: implications for the initial radiations of Somphospondyli and Titanosauria. Zoological Journal of the Linnean Society 207(1). Oxford University Press (OUP). doi:10.1093/zoolinnean/zlag073 mannion2026a