Miragaia (meer-UH-guy-UH) was a stegosaur that lived in Late Jurassic Portugal about 150 million years ago ( Kimmeridgian to Tithonian of the Jurassic). It was discovered in 2009 by a paleontologist named Octávio Mateus. Miragaia also has one of the shortest names for dinosaurs. Miragaia stands for "Beatiful Earth Goddess" and to the village where it was first found and longicollum is in reference to its very long neck.
Miragaia was herbivorous, like all stegosaurs. It's closely related to the more famous Dacentrurus. Together, they form the clade Dacentrurinae.
It had several plates that went down along its back, possibly for thermal regulating or attracting mates and scaring off rivals or predators. It had long spikes that came out of each shoulder, possibly for display. It also had several spikes on its tail (thagomizers) that it could use to hit predators with or scare them off. It was a quadruped, and walked around on four stout, slow-moving legs, but Miragaia was so well defended it didn't need to run fast. One feature that sets Miragaia apart form other stegosaurs is its extended neck with 17 vertebrae in it. It grew to be about 20 ft (6 m) long from nose to tail, with the extended neck making up a lot of it.
This represents the culmination of a trend of longer necks seen in stegosaurians. Additionally, Miragaia had more neck vertebrae than most sauropods, dinosaurs known for their long necks, which contrasts with the traditional view of stegosaurians as low browsers with short necks. Only the Chinese sauropods Euhelopus, Mamenchisaurus, and Omeisaurus had as many neck vertebrae as Miragaia, with most sauropods of the Late Jurassic possessing only 12 to 15. Mateus and colleagues suggested that the long neck either allowed Miragaia to browse at a level that other herbivores were not exploiting, or that the neck arose due to sexual selection.
Miragaia longicollum was discovered during construction of a road. This meant that the entire back section of the animal was probably destroyed. However, the front half is well preserved: a partial skull (right premaxilla, partial left maxilla, left nasal, right postorbital, right and left angulars), 15 cervical vertebrae (atlas and axis are absent) with associated ribs, 2 dorsal vertebrae, both coracoids, scapulae, humeri, radii and ulnae, 1 metacarpal, 3 phalanges, 12 rib fragments, 1 cheveron, 1 dermal spine and 13 plates.
Some fragments of a juvenile were also found at the same location, intermingled with the bones of the holotype: a partial pelvis (left ilium and right pubics), 2 dorsal centra and 3 dorsal neural arches from a juvenile individual (specimen ML 433-A), which were assigned as a paratype to M. longicollum.
Further isolated remains have also been attributed to the genus.
PaleoecologyIn life, Miragaia would have coexisted with other stegosaurians, such as Stegosaurus ungulatus and Dacentrurus armatus; sauropods, like Supersaurus lourinhanensis, Zby atlanticus, Lusotitan atalaensis, Lourinhasaurus alenquerensis and Turiansaurus riodevensis; the ankylosaur Dracopelta zbyzeswskii; ornithopods Draconyx loureiroi, such as Eousdryosaurus nanohallucis; crocodilians, like Machimosurus huggi and theropods, such as Torvosaurus gurneyi, Allosaurus europaeus, Ceratosaurus dentisculcatus and Lourinhanosaurus antunesi.
In Popular CultureMiragaia was in the documentary Dinosaur Revolution, where a herd of them lived by a dried up watering hole and lived near a Dinheirosaurus herd and an Allosaurus. They then helped to take down a Torvosaurus when it nearly stepped on one of their babies.