Gasparinisaura

*Gasparinisaura cincosaltensis*

***Gasparinisaura*** (meaning "Gasparini's lizard") is a genus of herbivorous ornithopod dinosaur from the Late Cretaceous.

The first fossils of *Gasparinisaura* were in 1992 found in Argentina, near Cinco Saltos in Río Negro Province. The type species, *Gasparinisaura cincosaltensis*, was named and described in 1996 by Rodolfo Coria and Leonardo Salgado. The generic name honours Argentine palaeontologist Zulma Brandoni de Gasparini. The specific name refers to Cinco Saltos.

## Discovery

The holotype, MUCPv-208, was uncovered in a layer of the Anacleto Formation, dating from the early Campanian, about 83 million years old. It consists of a partial skeleton with skull, lacking much of the vertebral column. The paratype is MUCPv-212, a tail with lower hindlimb elements. In 1997 three additional specimens were described: MUCPv 213, a partial skeleton with skull; MCSPv 111, a postcranial skeleton; and MCSPv 112, a skull with hindlimbs and pelvis. The three later specimens represent juvenile individuals. In 2008 gastroliths present with all three juvenile specimens were described.

## Description

*Gasparinisaura* was a small bipedal herbivore. In 2010 Gregory S. Paul estimated the length at 1.7 metres, the weight at thirteen kilogrammes.

*Gasparinisaura* had a rounded head that was moderately elongated. The eye sockets were very large and placed in a high position. The rather long back of the head was pendant. The jugal had a front branch that was thin and wedged between the maxilla and the lacrimal; the back of the jugal was high and broad. The quadratojugal had a long ascending process touching the squamosal, a basal trait. The jaw joints were low. There were about twelve, rather large, maxillary or dentary teeth in each upper or lower jaw. The forelimbs were lightly built. The ilium was short and low, the pubis thin. The hindlimbs were relatively long and powerful, with a short thighbone and a long lower leg. The foot was long and the first metatarsal was reduced to a splint, a derived trait. The tail featured low plate-like triangular chevrons that were expanded towards the back, which is unique in the Euornithopoda.

The gastroliths discovered formed clusters of up to hundred-forty rounded and polished stones in the abdomen with an average stone diameter of about eight millimetres. Representing about 0.3% of total body weight, they were voluminous enough to function as a gastric mill, a function sometimes denied for sauropod gastroliths because of their insufficient relative mass, being an order of magnitude lower.

## Classification

Gasparinisaurus was originally considered by the describers to have been a basal hypsilophodont, the most basal member of the clade ornithopoda. A phylogenetic analysis included in the description of the Antarctic ornithopod Morrosaurus shows that the latter and Gasparinisaura are part of Elasmaria, a clade of hypsilophodonts known from South America, Antarctica and maybe Australia. Gasparinisaura would be the basalmost member of this group.

## JPInstitute.com Description

Gasparinisaura, a small member of the family of dinosaurs that included Iguanodon, was discovered in Argentina. Not very much of this dinosaur has been found, so scientists still aren't sure what it looked like. Members of this family are among the most common of all dinosaurs found, and its discovery in South America shows that the family spread through the entire Mesozoic world. It has also been suggested that Gasparinisaura may have had feathers.

## Dinosaur Field Guide Description

Gasparinisaura ("[Dr. Zulma B.] Gasparini's lizard") is one of the rare ornithopods, or beaked dinosaurs, from the middle of the Cretaceous Period. Remains of dinosaurs from this time span are so extremely rare, all the specimens in the world would fit in one small exhibit hall! Gasparinisaura is also one of those rare small dinosaurs that had a primitive body design. The features of its skeleton place it with the dryosaurs, from the Jurassic Period, but Gasparinisaura lived well into the Cretaceous Period-a time when the hadrosaurs, the most evolved of the ornithopods, had already appeared. Many features of the skull are primitive: for example, the teeth with low crowns (not much showing above the gum line) and the shortened face (later ornithopods have a long muzzle). Normally, the skull evolves faster than the body bones. But in Gasparinisaura,
the reverse has occurred. The hip bone is more like that of the later hadrosaurs. This indicates a dinosaur with a well. developed hip musculature.

### Fun Facts

Of the many groups of ornithopods, only Gasparinisaura and the hadrosaurs are known from South America.

### Trivia

The scientists who are studying the very small Gasparinisaura are the same scientists at work on the very large Giganotosaurus.

## Links

http://web.archive.org/web/20040806052410fw\_/http://www.jpinstitute.com/dinopedia/dinocards/dc\_gaspa.html