on display in Tomsk State University The material assigned to
Sibirotitan was found in the Shestakovo 1 locality of the
Ilek Formation, deposited in a cliff on the
Kiya River's right bank, near
Shestakovo Village in
Kemerovo Province, West
Siberia,
Russia. Vertebrate remains were first recovered in 1953, and larger dinosaur fossils were found later in the sixties. Definitive sauropod remains were first discovered during expeditions in 1994 and 1995. Specimens would continue to turn up, and in 2018, Averianov
et al. would name those which could be confidently referred to as the same taxon as
S. astrosacralis; this included teeth, a sacrum, assorted vertebrae, and the previously described foot. This made it the second sauropod species named from the country, after
Tengrisaurus, named earlier in the same year; the genus
Arkharavia, named in 2010, although originally described as a sauropod, was later reassigned to
Hadrosauridae. The final name of
Sibirotitan was derived from
Siberia, where it was found, and the
Greek Τιτάν (
titan), the second group of divine beings in
Greek Mythology, preceding the
Olympians. The specific name
S. astrosacralis is derived from the Greek ἄστρον, meaning "star", and
Latin os sacrum, meaning "sacred bone". This refers to the star-like way in which the sacral ribs radiate in dorsal view. The authors noted that
Sibirotitan was one of the oldest titanosauriform species discovered in Asia. More primitive known species were found in other parts of the world, such as
Europe,
North America, or
Gondwana.
Sibirotitan, alongside
Fukuititan, are the first to appear in the Asian fossil record, both thought to have lived in the
Barremian age. Later relatives are well known from Asia afterwards, from the
Aptian through to the
Santonian, and it is proposed that one of these later taxa could have given rise to the
Lithostrotia, a titanosaur group whose earliest representatives are Asian genera such as
Tengrisaurus (from the Barremian or Aptian of Russia) and
Jiangshanosaurus (from the Albian of
China). The latter was noted to have similar
dorsal vertebrae to the much older
Sibirotitan. Most of the referred specimens, although dis-articulated, are thought to have belonged to a single individual; it was suggested the large remains found in the 1960s could have originally been from the same skeleton as later remains, some found as recently as 2011. A singular
cervical centrum was noted to be juvenile, and from a different individual, as the rest of the remains belonged to an adult animal. Among these fossils, PM TGU 120/10-Sh1-22, a dorsal vertebra, was selected as the
holotype specimen. An axis vertebra from the type locality was later assigned to
Sibirotitan astrosacralis as well. ==Description==