Amargatitanis

Superregnum: Eukaryota
Cladus: Unikonta
Cladus: Opisthokonta
Cladus: Holozoa
Regnum: Animalia
Subregnum: Eumetazoa
Cladus: Bilateria
Cladus: Nephrozoa
Superphylum: Deuterostomia
Phylum: Chordata
Subphylum: Vertebrata
Infraphylum: Gnathostomata
Megaclassis: Osteichthyes
Cladus: Sarcopterygii
Cladus: Rhipidistia
Cladus: Tetrapodomorpha
Cladus: Eotetrapodiformes
Cladus: Elpistostegalia
Superclassis: Tetrapoda
Cladus: Reptiliomorpha
Cladus: Amniota
Classis: Reptilia
Cladus: Eureptilia
Cladus: Romeriida
Subclassis: Diapsida
Cladus: Sauria
Infraclassis: Archosauromorpha
Cladus: Crurotarsi
Divisio: Archosauria
Cladus: Avemetatarsalia
Cladus: Ornithodira
Subtaxon: Dinosauromorpha
Cladus: Dinosauriformes
Cladus: Dracohors
Cladus: Dinosauria
Ordo: Saurischia
Cladus: Eusaurischia
Subordo: †Sauropodomorpha
Cladus: †Bagualosauria
Cladus: †Plateosauria
Cladus: †Massopoda
Cladus: †Sauropodiformes
Cladus: †Anchisauria
Infraordo: †Sauropoda
Cladus: †Gravisauria
Cladus: †Eusauropoda
Cladus: †Neosauropoda
Superfamilia: †Diplodocoidea

Familia: †Dicraeosauridae
Genus: †Amargatitanis

Amargatitanis (meaning "Amarga giant") is a genus of dicraeosaurid sauropod dinosaur (a type of large, long-necked quadrupedal herbivorous dinosaur) from the Barremian-age (Lower Cretaceous) La Amarga Formation of Neuquén, Argentina.
Classification

The holotype, MACN PV N53, which was collected in March 1983 by José Fernando Bonaparte, consists of two tail vertebrae, a right ischium, and a partial right hindlimb. Although classified as a titanosaur in the original description, the titanosaur placement of Amargatitanis was subsequently questioned by later authors, who noted that a scapula (MACM PV N34) and six tail vertebrae (MACN PV N51) seen as syntypes of Amargatitanis were found at a different locality than MACN PV N53 and that putative titanosaur characters of the genus were invalid.[1][2][3] A 2016 re-evaluation by Pablo Ariel Gallina reclassified Amargatitanis as a dicraeosaurid.[4]
References

Apesteguía, Sebastián (2007). "The sauropod diversity of the La Amarga Formation (Barremian), Neuquén (Argentina)". Gondwana Research. 12 (4): 533–546. Bibcode:2007GondR..12..533A. doi:10.1016/j.gr.2007.04.007.
D'Emic, M. D. (2012). "The early evolution of titanosauriform sauropod dinosaurs" (PDF). Zoological Journal of the Linnean Society. 166 (3): 624–671. doi:10.1111/j.1096-3642.2012.00853.x.
Mannion, Philip D.; Upchurch, Paul; Barnes, Rosie N.; Mateus, Octávio (2013). "Osteology of the Late Jurassic Portuguese sauropod dinosaur Lusotitan atalaiensis (Macronaria) and the evolutionary history of basal titanosauriforms" (PDF). Zoological Journal of the Linnean Society. 168: 98–206. doi:10.1111/zoj.12029.
Gallina, Pablo Ariel (2016). "Reappraisal Of The Early Cretaceous Sauropod Dinosaur Amargatitanis macni (Apesteguía, 2007), From Northwestern Patagonia, Argentina". Cretaceous Research. 64: 79–87. doi:10.1016/j.cretres.2016.04.002.