Turiasauria is an unranked

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 ...

of eusauropod dinosaurs known from Middle Jurassic to Early Cretaceous deposits in Europe, North America, and Africa.

Description

Turiasauria was originally erected by Royo-Torres et al. (2006) to include '' Turiasaurus'', '' Galvesaurus'' and '' Losillasaurus'', all of which hail from the Villar del Arzobispo Formation (

Tithonian In the geological timescale, the Tithonian is the latest age (geology), age of the Late Jurassic Epoch and the uppermost stage (stratigraphy), stage of the Upper Jurassic Series. It spans the time between 149.2 ±0.7 annum, Ma and 143.1 ±0.6 (mi ...

Berriasian In the geological timescale, the Berriasian is an age/ stage of the Early/Lower Cretaceous. It is the oldest subdivision in the entire Cretaceous. It has been taken to span the time between 143.1 ±0.6 Ma and 137.05 ± 0.2 (million years ago) ...

) of

Spain Spain, or the Kingdom of Spain, is a country in Southern Europe, Southern and Western Europe with territories in North Africa. Featuring the Punta de Tarifa, southernmost point of continental Europe, it is the largest country in Southern Eur ...

. Turiasuria was defined by the authors as "all

Eusauropoda Eusauropoda (meaning "True Lizard Foot") is a derived clade of sauropod dinosaurs. Eusauropods represent the node-based group that includes all descendant sauropods starting with the basal eusauropods of '' Shunosaurus'', and possibly '' Barapas ...

closer to ''Turiasaurus riodevensis'' than to '' Saltasaurus loricatus''". Cladistic analysis (Royo-Torres ''et al.'', 2006; 1927) of 309 characters and 33 taxa suggests that the turiasaurians lie outside the Neosauropoda and form a

monophyletic In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria: # the grouping contains its own most recent co ...

group. The clade is diagnosed by the presence of vertical neural spines, posterior centroparapohyseal laminae on the

dorsal Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage The fus ...

vertebra Each vertebra (: vertebrae) is an irregular bone with a complex structure composed of bone and some hyaline cartilage, that make up the vertebral column or spine, of vertebrates. The proportions of the vertebrae differ according to their spina ...

e, the absence of pre- and postspinal laminae on the dorsal vertebrae, the absence of a

scapula The scapula (: scapulae or scapulas), also known as the shoulder blade, is the bone that connects the humerus (upper arm bone) with the clavicle (collar bone). Like their connected bones, the scapulae are paired, with each scapula on either side ...

r acromial crest, the presence of a prominent humeral deltopectoral crest, medial deflection of the

proximal Standard anatomical terms of location are used to describe unambiguously the anatomy of humans and other animals. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position prov ...

end of the humerus, and a distinct vertical ridge on the caudal side of the

distal Standard anatomical terms of location are used to describe unambiguously the anatomy of humans and other animals. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position provi ...

half of the

ulna The ulna or ulnar bone (: ulnae or ulnas) is a long bone in the forearm stretching from the elbow to the wrist. It is on the same side of the forearm as the little finger, running parallel to the Radius (bone), radius, the forearm's other long ...

Paleobiogeography

Turiasaurs were initially considered confined to Europe, with '' Turiasaurus'' from Spain and '' Zby'' from Portugal, and the tooth taxa ''Cardiodon'', ''Neosodon'', and ''Oplosaurus'' were referred to the clade, but additional members were found in North America and Africa. Heart-shaped teeth are considered a synapomorphy of the turiasauria. Recently a heart shaped tooth found from the Jaisalmer Formation confirmed the presence of this clade in India during the Middle Jurassic (

Bathonian In the geologic timescale the Bathonian is an age (geology), age and stage (stratigraphy), stage of the Middle Jurassic. It lasted from approximately 168.2 ±1.2 annum, Ma to around 165.3 ±1.1 Ma (million years ago). The Bathonian Age succeeds ...

). Together with the '' Narindasaurus'' from the Bathonian of Madagascar, these are the oldest records of the group. It is therefore suggested that Turiasauria might have originated in

Gondwana Gondwana ( ; ) was a large landmass, sometimes referred to as a supercontinent. The remnants of Gondwana make up around two-thirds of today's continental area, including South America, Africa, Antarctica, Australia (continent), Australia, Zea ...

during the Middle Jurassic. A tooth discovered in the Lower Pliensbachian (Lower Jurassic) Hasle Formation of

Bornholm Bornholm () is a List of islands of Denmark, Danish island in the Baltic Sea, to the east of the rest of Denmark, south of Sweden, northeast of Germany and north of Poland. Strategically located, Bornholm has been fought over for centuries. I ...

, NHMD 1185136, was also referred to the family, being, if truly a member, 17 My older than any previously known turiasaur. North American '' Mierasaurus'' and '' Moabosaurus'' from the Early Cretaceous are also considered to be turiasaurs. Remains of a very large species of turiasaur, not yet formally identified, have recently been unearthed from the earliest Cretaceous (

) aged Angeac-Charente bonebed in western France.Ronan Allain, Romain Vullo, Lee Rozada, Jérémy Anquetin, Renaud Bourgeais, et al.
Vertebrate paleobiodiversity of the Early Cretaceous (Berriasian) Angeac-Charente Lagerstätte (southwestern France): implications for continental faunal turnover at the J/K boundary
Geodiversitas, Museum National d’Histoire Naturelle Paris, In press. ffhal-03264773fAllain, Ronan, editor (2017): ''Dinosaures. Les géants du vignoble''. Angoulême: Eidola éditions, 248 p. Indeterminate turiasaur material, consisting of a single vertebra, has been described from an unknown locality in the Early Cretaceous

Wealden Group The Wealden Group, occasionally also referred to as the Wealden Supergroup, is a group (stratigraphy), group (a sequence of rock strata) in the lithostratigraphy of southern England. The Wealden group consists of wiktionary:paralic, paralic to c ...

of England.

Classification

Turiasauria is classified as a group of the clade

, more derived than basal sauropods such as ''

Vulcanodon ''Vulcanodon'' (meaning "volcano tooth") is an extinct genus of sauropod dinosaur from the Early Jurassic Uppermost Forest Sandstone of southern Africa. The only known species is ''V. karibaensis''. Discovered in 1969 in Zimbabwe, it was regard ...

'', but outside of the advanced sauropod clade

Neosauropoda Neosauropoda is a clade within Dinosauria, coined in 1986 by Argentina, Argentine paleontologist José Bonaparte and currently described as ''Saltasaurus loricatus'', ''Diplodocus longus'', and all animals directly descended from their most recent ...

. Cladogram of Sauropoda after Holwerda et al. 2021, showing the position of Turiasauria within Eusauropoda:''Turiasaurus'' demonstrates that the

evolution Evolution is the change in the heritable Phenotypic trait, characteristics of biological populations over successive generations. It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, re ...

of enormous body size was not restricted to neosauropod clades such as the Diplodocidae and

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

, but developed independently at least once in a lineage of more basal sauropods, the turiasaurians. A 2009 thesis published by José Barco proposed that neither ''Galvesaurus'' nor ''Losillasaurus'' were turiasaurians. Later, a master thesis by Francisco Gascó (2009) and Royo-Torres et al. (2009) reaffirmed the validity of Turiasauria.

References

Sources

* Barco, J. L., Canudo, J. L., Cuenca-Bescós, G. & Ruíz-Omeñaca, J. I., (2005): Un nuevo dinosaurio saurópodo, ''Galvesaurus herreroi'' gen. nov., sp. nov., del tránsito Jurásico-Cretácico en Galve (Teruel, NE de España). ''Naturaleza Aragonesa'': Vol. 15, pp 4–17 * *

External links

* {{Taxonbar, from=Q3183209 Dinosaur clades