Amargasaurus fossil map
Where fossils of Amargasaurus have been found, shown on the Earth as it looked about 130 million years ago and on today’s map.
Dots are fossil collections recorded in the Paleobiology Database. The “then” view moves today’s fossil sites back to their positions 130 million years ago (the time slice nearest the median age of the fossils) using the Merdith et al. (2021) plate model; positions are approximate. Open on the timeline map →
| Group | Sauropods & prosauropods |
|---|---|
| Lived | 125.77–121.4 million years ago (Barremian) |
| Periods | Cretaceous |
| Family | Dicraeosauridae |
| Named by | Bonaparte 1984 |
| Fossil records | 2 occurrences at 2 locations (PBDB) |
| Found in | Argentina |
| Rock formations | La Amarga |
About Amargasaurus
Amargasaurus (; "La Amarga lizard") is a genus of sauropod dinosaur from the Early Cretaceous epoch (130–120 mya) of what is now Argentina. The only known skeleton was discovered in 1984 and is virtually complete, including a fragmentary skull, making Amargasaurus one of the best-known sauropods of its epoch. Amargasaurus was first described in 1991 and contains a single known species, Amargasaurus cazaui. It was a large animal, but small for a sauropod, reaching 9 to 13 meters (30 to 43 feet) in length. Most distinctively, it sported two parallel rows of tall spines down its neck and back, taller than in any other known sauropod. Several studies postulated that, in life, the spines stuck out of the body as individual structures that supported a horn sheath. Analysis of the bone structure suggests that the spines were connected by ligaments and could have formed a scaffold supporting a neck sail. They might have been used for display, combat, or defense.
Text in “About” is quoted from the Wikipedia article Amargasaurus (revision 1373737422), licensed under CC BY-SA 4.0; introduction excerpted verbatim, formatting removed. Ages, family, authority and fossil records: Paleobiology Database, accessed 22 October 2026. Ages are those of the rock layers the fossils were found in.
