| Moabosaurus | |
|---|---|
 | |
| Skeletal mount with skull based onCamarasaurus | |
Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Reptilia |
| Clade: | Dinosauria |
| Clade: | Saurischia |
| Clade: | †Sauropodomorpha |
| Clade: | †Sauropoda |
| Clade: | †Turiasauria |
| Genus: | †Moabosaurus Brittet al., 2017 |
| Type species | |
| †Moabosaurus utahensis Brittet al., 2017 | |
Moabosaurus (meaning "Moab reptile") is a genus ofturiasauriansauropod dinosaur from theEarly CretaceousCedar Mountain Formation ofUtah,United States.[1]
Moabosaurus is characterized by a suite of features including: extremely low neural spines that are thin, transverse ridges in the posterior cervical vertebrae and anterior dorsal vertebrae; strongly procoelous proximal and distal caudal vertebrae; and an ulna with well-developed lateral and medial anteroproximal ridges combined with a large olecranon process.[1]
According to the 2017 article which officially named and describedMoabosaurus, the animal was said to reach 10 meters (32.8 feet) long. However, the specimens which were examined belonged to juveniles and sub-adults, so it's possible that the creature measured longer when fully-grown.[1]
Moabosaurus was collected from the Dalton Wells Quarry, which is about 20 km northwest ofMoab, Utah. Between 1975 and 2005, the quarry produced parts of at least 18 individuals ofMoabosaurus based on the number of braincases present, totalling over 5,500 bones.[1] Many of the recovered bones are fragmentary due to intense trampling as evidenced by breakage and trample scratches.[2] Another factor that degraded the bones before burial was consumption by insects. Insects, probably beetle larvae, consumed portions of the bones that were in contact with the ground, as evidenced by burrows and mandible marks.[2] Later, the bones were transported a short distance by a stream and buried in sediments reworked from the underlying Morrison Formation.[3] Detrital zircon crystals from the Dalton Wells Quarry yield an age of 125 million years, indicatingMoabosaurus isAptian in age.[3]Brooks B. Britt, Rodney D. Scheets, Michael F. Whiting, and D. Ray Wilhite named Moabosaurus utahensis.
Phylogenetic analyses in the describing article in 2017 indicated thatMoabosaurus is a basal titanosauriform macronarian neosauropod. Unlike other titanosauriform sauropods it has thick-walled vertebrae with large pneumatic chambers (camerate-grade) as in basal macronarians and large, spatulate teeth, as inCamarasaurus.[1] However, a second study which was made in 2017 placed it in theTuriasauria, thus outside of theNeosauropoda. WithTuriasaurus it shares derived features of the braincase; bifurcated cervical (neck) ribs; extremely low neural spines on the cervical and anterior dorsal vertebrae; and strongly procoelous proximal caudal vertebrae.[4]
The Dalton Wells quarry has also yielded specimens ofVenenosaurus (a brachiosaurid sauropod), the theropod dinosaursUtahraptor andNedcolbertia, plus a tall-spinediguanodontian,[5] and the ankylosaurianGastonia. Non-dinosaurian taxa are rare at the quarry and are limited to fragments of apterosaur,crocodilian,turtle, and aneochoristodere.[6]
