| Nodosaurus | |
|---|---|
_(17529968373).jpg) | |
| Vertebrae and armor of the holotype | |
Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Reptilia |
| Clade: | Dinosauria |
| Clade: | †Ornithischia |
| Clade: | †Thyreophora |
| Clade: | †Ankylosauria |
| Family: | †Nodosauridae |
| Subfamily: | †Nodosaurinae |
| Genus: | †Nodosaurus Marsh, 1889 |
| Type species | |
| †Nodosaurus textilis | |
Nodosaurus (meaning 'knobbed lizard') is agenus ofherbivorousnodosauridankylosauriandinosaur from theLate Cretaceous, the fossils of which are found exclusively in theFrontier Formation inWyoming.
Fossils ofNodosaurus were first discovered on 17 July, 1881 by fossil collectorWilliam Harlow Reed inAlbany County, Wyoming in the western United States. This discovery was made during theBone Wars, a scientific competition between paleontologistsOthniel Charles Marsh andEdward Drinker Cope, and as part of an expedition to the Jurassic-aged strata of theMorrison Formation inComo Bluff. The remains, cataloged as YPM VP 1815 at theYale Peabody Museum inNew Haven, found included: 3dorsal and 13caudal vertebrae, 3dorsal ribs, fragmentaryforelimbs, a partialpelvis,femora,tibiae, partial leftpes, and severalosteoderms.[1][2][3] The fossils all came from a single quarry located around 1.5 miles (2.4 km) from Quarry 13 of Como Bluff.[3] However, the outcrop theNodosaurus skeleton was unearthed from comes from theFrontier Formation, also known as theDakota Sandstone, which dates to theCenomanianage of theLate Cretaceous period.[4][5]
In 1889, Othniel Charles Marshscientifically described the remains and assigned them to a newgenus andspecies of ornithischian dinosaur, which he namedNodosaurus textilis. The generic nameNodosaurus derives from theLatin "nodus" meaning "knobbed", a reference to the knobbed osteoderms of the animal, and the Latin "sauros" meaning "lizard", a common suffix for dinosaur names. The specific nametextilis refers to the textile-like appearance of the osteoderms. In his description, Marsh classifiedNodosaurus as a member ofStegosauria, a group of plated ornithsichians.[2] However the next year, Marsh classifiedNodosaurus in its own family,Nodosauridae, in the orderCeratopsia, a group of horned ornithischians.[6] In 1921, paleontologist Richard Swan Lull published a more comprehensive description ofNodosaurus in which he defined the family and the genus.[3] Later in 1978, paleontologist Walter Coombs Jr. hypothesized that the other nodosauridsStegopelta andHierosaurus were synonyms ofNodosaurus,[7] but this has seen little support.[8][9][10]
_(18147021802).jpg)
Nodosaurus grew up to roughly 4 to 6 metres (13 to 20 ft) long and it was anornithischian dinosaur with bony dermal plates covering the top of its body, and it may have had spikes along its side as well. The dermal plates were arranged in bands along its body, with narrow bands over the ribs alternating with wider plates in between. These wider plates were covered in regularly arranged bony nodules, which give the animal its scientific name.[11] In 2010Paul estimated its length at 6 meters (20 ft) and its weight at 3.5 tonnes (3.85 short tons).[12]
It had four short legs, five-toed feet, a short neck, and a long, stiff, clubless tail. The head was narrow, with a pointed snout, powerful jaws, and small teeth.[11] It perhaps ate soft plants, as it would have been unable to chew tough, fibrous ones; or alternatively it may have processed the latter withgastroliths and its enormous intestinal apparatus.
Within Nodosauridae,Nodosaurus falls out in the subfamily Nodosaurinae, formally defined as the largest clade containingNodosaurus textilis but notHylaeosaurus armatus,Mymoorapelta maysi andPolacanthus foxii.[8] The2018 phylogenetic analysis of Nodosauridae by Rivera-Sylva and colleagues is below.[10]
