Laurasiformes (meaning "

Laurasia Laurasia () was the more northern of two large landmasses that formed part of the Pangaea supercontinent from around ( Mya), the other being Gondwana. It separated from Gondwana (beginning in the late Triassic period) during the breakup of Pa ...

n forms") is an

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

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 b ...

dinosaurs from the late

Early Cretaceous The Early Cretaceous (geochronology, geochronological name) or the Lower Cretaceous (chronostratigraphy, chronostratigraphic name) is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 143.1 ...

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

North North is one of the four compass points or cardinal directions. It is the opposite of south and is perpendicular to east and west. ''North'' is a noun, adjective, or adverb indicating Direction (geometry), direction or geography. Etymology T ...

and

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

. It was defined in

2009 2009 was designated as the International Year of Astronomy by the United Nations to coincide with the 400th anniversary of Galileo Galilei's first known astronomical studies with a telescope and the publication of Astronomia Nova by Joha ...

by the Spanish paleontologist

Rafael Royo-Torres Dr. Rafael Royo-Torres is a Spanish Paleontologist. He works in Fundación Conjunto Paleontológico de Teruel-Dinópolis, in Teruel, Spain Spain, or the Kingdom of Spain, is a country in Southern Europe, Southern and Western Europe with ...

as a clade containing sauropods more closely related to ''

Tastavinsaurus ''Tastavinsaurus'' is a genus of sauropod dinosaur belonging to the Titanosauriformes. It is based on a partial skeleton from the Early Cretaceous Xert Formation of Spain. The type species is ''Tastavinsaurus sanzi'', named in honor of the Rio ...

'' than to ''

Saltasaurus ''Saltasaurus'' (which means "lizard from Salta") is a genus of saltasaurid dinosaur of the Late Cretaceous Period (geology), period of Argentina. Small among sauropods, though still heavy by the standards of modern creatures, ''Saltasaurus'' was ...

''. Genera purported to form part of this clade include '' Aragosaurus'', ''

Galvesaurus ''Galvesaurus'', or ''Galveosaurus'', (meaning " Galve lizard") is a genus of brachiosaurid sauropod dinosaur from the Late Jurassic period. Fossils of the only known species, ''G. herreroi'', were found in Galve, Spain, hence its generic name, ...

'', ''

Phuwiangosaurus ''Phuwiangosaurus'' (meaning "Phu Wiang lizard") is a genus of titanosaur dinosaur from the Early Cretaceous (Valanginian-Hauterivian) Sao Khua Formation of Thailand. The type species, ''P. sirindhornae'', was described by Martin, Buffetaut, and ...

'', ''

Venenosaurus ''Venenosaurus'' ( ) is a genus of sauropod dinosaur that lived in what is now Utah during the Early Cretaceous. Its type and only species is ''Venenosaurus dicrocei''. Fossils of ''Venenosaurus'' were first discovered in 1998, by Denver Museum o ...

'', ''

Cedarosaurus ''Cedarosaurus'' (meaning "Cedar lizard" - named after the Cedar Mountain Formation, in which it was discovered) is a genus of nasal-crested macronarian dinosaur from the Early Cretaceous Period (Valanginian). It was a sauropod which lived in wha ...

'', '' Tehuelchesaurus'', ''

Sonorasaurus ''Sonorasaurus'' is a genus of brachiosaurid dinosaur from the Early to Late Cretaceous (Albian to Cenomanian stages, around 112 to 93 million years ago). It was a herbivorous sauropod whose fossils have been found in southern Arizona in th ...

'' and ''Tastavinsaurus''. Its exact position and validity is uncertain and varies between authors. A cladistics analysis found a similar grouping outside

Titanosauriformes Macronaria is a clade of sauropod dinosaurs. Macronarians are named after the large diameter of the nasal opening of their skull, known as the external naris, which exceeded the size of the orbit, the skull opening where the eye is located (hence ...

and basal within the Camarasauromorpha, while others have placed them inside

Somphospondyli Somphospondyli is an extinct clade of titanosauriformes, titanosauriform sauropods that lived from the Late Jurassic until the end of the Late Cretaceous, comprising all titanosauriforms more closely related to Titanosauria proper than Brachiosau ...

Brachiosauridae The Brachiosauridae ("arm lizards", from Greek ''brachion'' (βραχίων) = "arm" and ''sauros'' = "lizard") are a family or clade of herbivorous, quadrupedal sauropod dinosaurs. Brachiosaurids had long necks that enabled them to access the le ...

, consequently, it has been suggested that ''Tehuelchesaurus'' along with others of the previously mentioned genera, form two different clades outside titanosauriformes (Carbadillo et al., 2011) while a more recent cladistics analysis found no support for the existence of the clade, with a revision of its supporting features finding them problematic due to being poorly defined, not present on most of the "laurasiforms" or being features present in many sauropods of other clades.

References

Macronaria Taxa described in 2009 Valanginian first appearances Cenomanian extinctions {{sauropodomorph-stub