| Meaning | Named after “Maraapuni” (indigenous name) [Maraapuni-saurus] |
| Pronunciation | ma-RAH-poo-nee-sore-us |
| When: | Late Jurassic (about 150 million years ago) |
| Where: | North America (USA, Colorado) |
| What: | Sauropod (rebbachisaurid) |
| Weight: | Highly speculative, estimated around 100 metric tons (due to fragmentary evidence) |
| Length: | Estimated around 30 meters (98 feet) or more |
| Diet: | Herbivorous (ate high vegetation) |
| Discovered: | First described by Edward Drinker Cope in 1878 (as Amphicoelias fragillimus, reclassified later) |
Known from just one vertibrae.