Pararhabdodon
Encyclopedia
Pararhabdodon was a genus
of derived hadrosauroid or basal hadrosaurid
dinosaur
, from the Maastrichtian
-age Upper Cretaceous Tremp Formation
of Spain
. It is based on assorted postcranial remains, mostly vertebrae, and is notable for the reassignments it has undergone in regards to classification.
, including a cervical
vertebra, some partial dorsals
, a humerus
, and a fragmentary scapula
, as Rhabdodon
sp. New remains from this site (Tremp Formation, near Isona, Lleida
, Spain
) brought about a reconsideration of the material, and Casanovas-Cladellas et al. named Pararhabdodon isonense in 1993 from a middle caudal
vertebra (IPS-SRA-15), referring additional material to their new genus. At the time, it was considered to be a rhabdodont-like basal iguanodont
, hence the name.
Additional material from the type locality was collected in 1994, and the species name was corrected to isonensis in 1997 by Casanovas-Cladellas et al. and Laurent et al. A dentary (IPS SRA 27) from a second quarry in the Tremp Formation
was also referred to the genus, now considered to be a basal lambeosaurine
hadrosaurid
. Laurent et al. referred additional remains (jaw material, vertebrae, and limb bones of multiple individuals of different ages) from the uppermost Cretaceous
of Aude
, France
, to the genus, but this was not discussed in the most recent review. (Oddly, the second edition of The Dinosauria omitted this genus altogether)
Head (2001) disputed the assignment to the Lambeosaurinae, considering it more likely to be basal to the two hadrosaurid subfamilies. This is the same conclusion that Prieto-Marquez et al. (2006) came to, finding it to be the sister group to Hadrosaurinae+Lambeosaurinae ( = Hadrosauridae in their analysis, although the definition of Hadrosauridae varies). Prieto-Marquez assigned IPS SRA 27 to its own genus, Koutalisaurus
, a more derived hadrosaurid. More recent research by Prieto-Marquez and Wagner considers Koutalisaurus a probable synonym of Pararhabdodon, and Pararhabdodon a member of a lambeosaurine clade
with the Chinese genus Tsintaosaurus
.
al-quadruped
al herbivore
, in the neighborhood of 6 m (19.7 ft) long, fully grown. The dorsal and sacral
neural spines were elongate, so the animal would have had a tall back, like other hadrosaurids. Because the material is sparse, more specific conclusions cannot be reached. Spanish material includes: a maxilla
; four cervical, four dorsal, and a caudal vertebra; a sacrum; the end of an ischium; and a humerus
.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of derived hadrosauroid or basal hadrosaurid
Hadrosaurid
Hadrosaurids or duck-billed dinosaurs are members of the family Hadrosauridae, and include ornithopods such as Edmontosaurus and Parasaurolophus. They were common herbivores in the Upper Cretaceous Period of what are now Asia, Europe and North America. They are descendants of the Upper...
dinosaur
Dinosaur
Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...
, from the Maastrichtian
Maastrichtian
The Maastrichtian is, in the ICS' geologic timescale, the latest age or upper stage of the Late Cretaceous epoch or Upper Cretaceous series, the Cretaceous period or system, and of the Mesozoic era or erathem. It spanned from 70.6 ± 0.6 Ma to 65.5 ± 0.3 Ma...
-age Upper Cretaceous Tremp Formation
Tremp Formation
The Tremp Formation is a geological formation in Huesca, Spain whose strata date back to the Late Cretaceous. Dinosaur remains are among the fossils that have been recovered from the formation....
of Spain
Spain
Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...
. It is based on assorted postcranial remains, mostly vertebrae, and is notable for the reassignments it has undergone in regards to classification.
History
In 1987, Casanovas et al. described remains of an ornithopod from northeastern SpainSpain
Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...
, including a cervical
Neck
The neck is the part of the body, on many terrestrial or secondarily aquatic vertebrates, that distinguishes the head from the torso or trunk. The adjective signifying "of the neck" is cervical .-Boner anatomy: The cervical spine:The cervical portion of the human spine comprises seven boney...
vertebra, some partial dorsals
Dorsum (biology)
In anatomy, the dorsum is the upper side of animals that typically run, fly, or swim in a horizontal position, and the back side of animals that walk upright. In vertebrates the dorsum contains the backbone. The term dorsal refers to anatomical structures that are either situated toward or grow...
, a humerus
Humerus
The humerus is a long bone in the arm or forelimb that runs from the shoulder to the elbow....
, and a fragmentary scapula
Scapula
In anatomy, the scapula , omo, or shoulder blade, is the bone that connects the humerus with the clavicle ....
, as Rhabdodon
Rhabdodon
Rhabdodon is a genus of dinosaur that lived in Europe approximately 70 million years ago in the Late Cretaceous. It is unclear whether it was an iguanodont or a hypsilophodont, and may be a "missing link" between the two. Current evidence indicates it is an iguanodont similar to Tenontosaurus...
sp. New remains from this site (Tremp Formation, near Isona, Lleida
Lleida (province)
thumb|250px|Monastery of [[Santa Maria de Bellpuig de les Avellanes]].Lleida is a province of north-eastern Spain, in the western part of the autonomous community of Catalonia. It is bordered by the provinces of Girona, Barcelona, Tarragona, Zaragoza and Huesca and the countries of France and...
, Spain
Spain
Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...
) brought about a reconsideration of the material, and Casanovas-Cladellas et al. named Pararhabdodon isonense in 1993 from a middle caudal
Tail
The tail is the section at the rear end of an animal's body; in general, the term refers to a distinct, flexible appendage to the torso. It is the part of the body that corresponds roughly to the sacrum and coccyx in mammals, reptiles, and birds...
vertebra (IPS-SRA-15), referring additional material to their new genus. At the time, it was considered to be a rhabdodont-like basal iguanodont
Iguanodont
Iguanodonts were herbivorous dinosaurs that lived from the mid-Jurassic to Late Cretaceous. Some members include Camptosaurus, Callovosaurus, Iguanodon, Ouranosaurus, and the hadrosaurids or "duck-billed dinosaurs". Iguanodonts were one of the first groups of dinosaurs to be found...
, hence the name.
Additional material from the type locality was collected in 1994, and the species name was corrected to isonensis in 1997 by Casanovas-Cladellas et al. and Laurent et al. A dentary (IPS SRA 27) from a second quarry in the Tremp Formation
Tremp Formation
The Tremp Formation is a geological formation in Huesca, Spain whose strata date back to the Late Cretaceous. Dinosaur remains are among the fossils that have been recovered from the formation....
was also referred to the genus, now considered to be a basal lambeosaurine
Lambeosaurinae
Lambeosaurinae is a group of crested hadrosaurid dinosaurs.-Classification:Lambeosaurines have been split into Parasaurolophini and Corythosaurini . Corythosaurini and Parasaurolophini as terms entered the formal literature in Evans and Reisz's 2007 redescription of Lambeosaurus magnicristatus...
hadrosaurid
Hadrosaurid
Hadrosaurids or duck-billed dinosaurs are members of the family Hadrosauridae, and include ornithopods such as Edmontosaurus and Parasaurolophus. They were common herbivores in the Upper Cretaceous Period of what are now Asia, Europe and North America. They are descendants of the Upper...
. Laurent et al. referred additional remains (jaw material, vertebrae, and limb bones of multiple individuals of different ages) from the uppermost Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...
of Aude
Aude
Aude is a department in south-central France named after the river Aude. The local council also calls the department "Cathar Country".Aude is also a frequent feminine French given name in Francophone countries, deriving initially from Aude or Oda, a wife of Bertrand, Duke of Aquitaine, and mother...
, France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
, to the genus, but this was not discussed in the most recent review. (Oddly, the second edition of The Dinosauria omitted this genus altogether)
Head (2001) disputed the assignment to the Lambeosaurinae, considering it more likely to be basal to the two hadrosaurid subfamilies. This is the same conclusion that Prieto-Marquez et al. (2006) came to, finding it to be the sister group to Hadrosaurinae+Lambeosaurinae ( = Hadrosauridae in their analysis, although the definition of Hadrosauridae varies). Prieto-Marquez assigned IPS SRA 27 to its own genus, Koutalisaurus
Koutalisaurus
Koutalisaurus was a genus of hadrosaurid dinosaur. It is based on a mostly complete dentary from the Maastrichtian-age Upper Cretaceous Tremp Formation near the town of Abella de la Conca, Lleida, Spain...
, a more derived hadrosaurid. More recent research by Prieto-Marquez and Wagner considers Koutalisaurus a probable synonym of Pararhabdodon, and Pararhabdodon a member of a lambeosaurine clade
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...
with the Chinese genus Tsintaosaurus
Tsintaosaurus
Tsintaosaurus is a genus of hadrosaurid dinosaur from China. It was about long, tall and weighed 3 tons. The type species is T. spinorhinus, first described by C. C...
.
Paleobiology
Pararhabdodon most likely was a bipedBiped
Bipedalism is a form of terrestrial locomotion where an organism moves by means of its two rear limbs, or legs. An animal or machine that usually moves in a bipedal manner is known as a biped , meaning "two feet"...
al-quadruped
Quadruped
Quadrupedalism is a form of land animal locomotion using four limbs or legs. An animal or machine that usually moves in a quadrupedal manner is known as a quadruped, meaning "four feet"...
al herbivore
Herbivore
Herbivores are organisms that are anatomically and physiologically adapted to eat plant-based foods. Herbivory is a form of consumption in which an organism principally eats autotrophs such as plants, algae and photosynthesizing bacteria. More generally, organisms that feed on autotrophs in...
, in the neighborhood of 6 m (19.7 ft) long, fully grown. The dorsal and sacral
Sacrum
In vertebrate anatomy the sacrum is a large, triangular bone at the base of the spine and at the upper and back part of the pelvic cavity, where it is inserted like a wedge between the two hip bones. Its upper part connects with the last lumbar vertebra, and bottom part with the coccyx...
neural spines were elongate, so the animal would have had a tall back, like other hadrosaurids. Because the material is sparse, more specific conclusions cannot be reached. Spanish material includes: a maxilla
Maxilla
The maxilla is a fusion of two bones along the palatal fissure that form the upper jaw. This is similar to the mandible , which is also a fusion of two halves at the mental symphysis. Sometimes The maxilla (plural: maxillae) is a fusion of two bones along the palatal fissure that form the upper...
; four cervical, four dorsal, and a caudal vertebra; a sacrum; the end of an ischium; and a humerus
Humerus
The humerus is a long bone in the arm or forelimb that runs from the shoulder to the elbow....
.