''Lirainosaurus'' (meaning "slender lizard"; from the Basque ''lirain'', meaning "slender", and the Greek ''sauros'', meaning "lizard")is a genus of

titanosaur Titanosaurs (or titanosaurians; members of the group Titanosauria) were a diverse group of sauropod dinosaurs, including genera from all seven continents. The titanosaurs were the last surviving group of long-necked sauropods, with taxa still th ...

sauropod Sauropoda (), whose members are known as sauropods (; from '' sauro-'' + '' -pod'', 'lizard-footed'), is a clade of saurischian ('lizard-hipped') dinosaurs. Sauropods had very long necks, long tails, small heads (relative to the rest of their bo ...

which lived in what is now

Spain , image_flag = Bandera de España.svg , image_coat = Escudo de España (mazonado).svg , national_motto = ''Plus ultra'' (Latin)(English: "Further Beyond") , national_anthem = (English: "Royal March") , i ...

. The

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen ...

, ''Lirainosaurus astibiae'', was described by Sanz, Powell, Le Loeuff, Martinez, and Pereda-Suberbiola in 1999. It was a relatively small sauropod, measuring long, possibly up to long for the largest individuals, and weighed about .

Classification

This genus was based on a skull fragment, isolated teeth, several vertebrae including the

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...

- an anterior caudal vertebra, and appendicular bones from the Late Cretaceous of

Laño Laño ( eu, Lañu) is a hamlet and '' concejo'' (a small administrative subdivision) in Condado de Treviño within the Treviño enclave; which is administratively part of the Spanish province of Burgos, but which is completely surrounded by the ...

(northern Spain). New material from Laño, Spain described by Diaz ''et al.'' (2013), which includes cervical, dorsal and caudal vertebrae, dorsal ribs, and a haemal arch, has been assigned to ''Lirainosaurus''. According to Diaz ''et al.'', ''Lirainosaurus'' can be distinguished by the presence of a lamina in the interzygapophyseal

fossa Fossa may refer to: Animals * Fossa (animal), the common name of a carnivoran mammal of genus ''Cryptoprocta'' endemic to Madagascar * ''Fossa'', the Latin genus name of the Malagasy civet, a related but smaller mammal endemic to Madagascar Pla ...

of the most proximal caudal vertebrae; and the spinopostzygapophyseal structure not posteriorly projected in the posterior caudal vertebrae. With respect to

phylogeny A phylogenetic tree (also phylogeny or evolutionary tree Felsenstein J. (2004). ''Inferring Phylogenies'' Sinauer Associates: Sunderland, MA.) is a branching diagram or a tree showing the evolutionary relationships among various biological spec ...

, the combination of characters present in the new axial remains described, supports the placement of ''Lirainosaurus'' as a derived lithostrotian titanosaur closely related to the

Saltasaurinae Saltasaurinae is a subfamily of titanosaurian sauropods known from the late Cretaceous period of South America, India and Madagascar. Description Saltasaurines are relatively small sauropods with the general body shape of a small head, long ne ...

. The results of an unpublished SVPCA abstract published in 2016 narrow down the exact position of ''Lirainosaurus'' by placing it as closer to ''

Alamosaurus ''Alamosaurus'' (; meaning "Ojo Alamo lizard") is a genus of opisthocoelicaudiine titanosaurian sauropod dinosaurs, containing a single known species, ''Alamosaurus sanjuanensis'', from the late Cretaceous Period of what is now southern North Am ...

'' and '' Opisthocoelicaudia'' than to ''Saltasaurus''. Later, Diez Diaz ''et al.'' (2018) erected Lirainosaurinae to accommodate ''Lirainosaurus'' as well as ''Ampelosaurus'' and ''Atsinganosaurus''.

Paleoenvironment

Specimens have been found in the North-Pyrenean site of Bellevue, which is located at the base of the Marnes de la Maurine member of the

Marnes Rouges Inférieures Formation The Marnes Rouges Inférieures Formation is a Late Cretaceous geologic formation found in the French Pyrenees. It predominantly consists of red mustone, with minor brown mudstone and sandstone.Fondevilla et al., 2016 Dinosaurs, dinosaur eggs and a ...

. Marine biostratigraphic testing of the formation places its age somewhere between Late Campanian to Early

Maastrichtian The Maastrichtian () is, in the ICS geologic timescale, the latest age (uppermost stage) of the Late Cretaceous Epoch or Upper Cretaceous Series, the Cretaceous Period or System, and of the Mesozoic Era or Erathem. It spanned the interval from ...

. Other contemporary dinosaurs in the Bellevue layer include the titanosaur sauropod ''

Ampelosaurus ''Ampelosaurus'' ( ; meaning "vine lizard") is a titanosaurian sauropod dinosaur from the Late Cretaceous Period of what is now France. Its type species is ''A. atacis'', named by Le Loeuff in 1995. A possible unnamed species has given ''Ampel ...

'', the

rhabdodontid Rhabdodontidae is a family of herbivorous iguanodontian ornithopod dinosaurs whose earliest stem members appeared in the middle of the Lower Cretaceous. The oldest dated fossils of these stem members were found in the Barremian Castrillo de la R ...

'' Rhabdodon'' and indeterminate

ankylosaur Ankylosauria is a group of herbivorous dinosaurs of the order Ornithischia. It includes the great majority of dinosaurs with armor in the form of bony osteoderms, similar to turtles. Ankylosaurs were bulky quadrupeds, with short, powerful limbs. ...

and Dromaeosauridae elements. Other material ascribed to ''Lirainosaurus'' have been found in the Fox-Amphoux–Métisson locality, where unfortunately no magnetostratigraphic dating has been performed. However, the local stratigraphy presents the same succession of facies as in the Aix-en-Provence Basin, which is also in the Late Campanian to Early Maastrichtian age.

References

Titanosaurs Late Cretaceous dinosaurs of Europe Campanian life Cretaceous Spain Fossils of Spain Fossil taxa described in 1999 {{Sauropodomorph-stub