Adamantisaurus

Adamantisaurus (/ˌædəmæntɪˈsɔːrəs/ AD-ə-man-ti-SAWR-əs) is a poorly-known genus of titanosaurian sauropod dinosaur from the Late Cretaceous Period of what is now South America. It is only known from six tail vertebrae but, as a sauropod, it can be assumed that this dinosaur was a very large animal with a long neck and tail.

Sculpture of Adamantisaurus

Adamantisaurus Temporal range: Late Cretaceous, 75 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Life reconstruction
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Dinosauria
Clade:	Saurischia
Suborder:	†Sauropodomorpha
Clade:	†Sauropoda
Clade:	†Titanosauria
Clade:	†Lithostrotia
Genus:	†Adamantisaurus Santucci & Bertini, 2006
Species:	†A. mezzalirai
Binomial name
†Adamantisaurus mezzalirai Santucci & Bertini, 2006

Like many titanosaurians, Adamantisaurus is incompletely known, making its exact relationships difficult to establish. However, similarities have been noted with Aeolosaurus and the Bauru Group titanosaurian formerly known as the "Peiropolis titanosaur", now called Trigonosaurus.

Description

As Adamantisaurus mezzalirai is only known from the anterior portion of the tail, relatively little is known about the anatomy of this species. It was probably a medium-sized titanosaur, roughly 13 meters long.[1]

Discovery and naming

Although this animal's remains were first mentioned in print in 1959, it was not named until the description written by Brazilian paleontologists Rodrigo Santucci and Reinaldo Bertini in 2006. It was the first dinosaur named in that year. The type specimen, the only material known of the genus, consists of the second through seventh caudal vertebrae and two chevrons.[2]

Adamantisaurus is currently known only from the Adamantina Formation of Brazil. The Adamantina Formation is part of the Bauru Group of geologic formations. The stratigraphy and exact age of the Bauru Group is still unsettled, but the Adamantina probably occurs somewhere between the Turonian through early Maastrichtian stages of the Late Cretaceous Period (93 to 70 million years ago). Adamantisaurus shares the Adamantina with fellow titanosaurian, Gondwanatitan.

Adamantisaurus is named after the Adamantina Formation in the Brazilian state of São Paulo, where the fossil was found and also incorporates the Greek word sauros meaning 'lizard', the most common suffix used in dinosaur names.[2] The type and only species, Adamantisaurus mezzalirai is named in honor of Sérgio Mezzalira, the Brazilian geologist who originally found the specimen and first mentioned it in print.

Classification

The phylogenetic relationship of Adamantisaurus has yet to be rigorously tested. However, it appears to be more derived than Malawisaurus based on the ball-and-socket articulation of the caudal vertebrae.[2] All titanosaurs at least as derived as Malawisaurus are members of the clade Lithostrotia.[3] Within that clade, however, its relationships are unclear. It is not a close relative of Saltasaurus. Adamantisaurus resembles Aeolosaurus, a close relative of its contemporary Gondwanatitan, in some respects. Adamantisaurus cannot be directly compared to Brasilotitan, another genus found in the Adamantina Formation.[4]

References

1. Paul, G. S. (2010). The Princeton Field Guide to Dinosaurs. Princeton University Press.
2. Santucci, R. M.; Bertini, R. J. (2006). "A new titanosaur from western São Paulo State, Upper Cretaceous Bauru Group, south-east Brazil". Palaeontology. 49 (1): 59–66. doi:10.1111/j.1475-4983.2005.00527.x. hdl:11449/33993.
3. 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. doi:10.1017/S1477201903001044.
4. Machado, E. B.; Avilla, L. D. S.; Nava, W. R.; Campos, D. D. A.; Kellner, A. W. A. (2013). "A new titanosaur sauropod from the Late Cretaceous of Brazil". Zootaxa. 3701 (3): 301–321. doi:10.11646/zootaxa.3701.3.1. PMID 26191585.

Further reading

• Mezzalira, S (1959). "Nota preliminar sobre as recentes descobertas paleontológicas no Estado de São Paulo, no período 1958–59". Notas Prévias do Instituto Geográfico e Geológico. 2: 1–7. [In Portuguese]
• Powell, J.E. 1987. Morfológia del esqueleto axial de los dinossaurios titanosáuridos (Saurischia, Sauropoda) del Estado de Minas Gerais, Brasil. In Anais X Congresso Brasileiro de Paleontologia, Rio de Janeiro. Rio de Janeiro: Sociedade Brasileira de Paleontologia. Pp. 155–171. [In Spanish]
• Powell, J.E. (2003). "Revision of South American titanosaurid dinosaurs: palaeobiological, palaeobiogeographical and phylogenetic aspects". Records of the Queen Victoria Museum. 111: 1–173.