Lanzhousaurus

Last updated

Lanzhousaurus
Temporal range: Lower Cretaceous, 130  Ma
O
S
D
C
P
T
J
K
Pg
N
Skeleton of Lanzhousaurus magnidens.jpg
Skeletal mount of Lanzhousaurus
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Ornithischia
Clade: Neornithischia
Clade: Ornithopoda
Clade: Styracosterna
Genus: Lanzhousaurus
You, Ji & Li, 2005
Type species
Lanzhousaurus magnidens
You, Ji & Li, 2005

Lanzhousaurus (meaning "Lanzhou lizard") is a genus of ornithopod dinosaur. Lanzhousaurus lived in the Gansu region of what is now China during the Early Cretaceous (Barremian). A partial skeleton has been recovered from the Hekou Group. It was described by You, Ji and Li in 2005 and the type and only species is Lanzhousaurus magnidens. [1] It's been estimated to be about 10 meters (33 feet) in length and 6 tonnes (6.6 short tons) in weight. [2]

Contents

Dentition

Jaw and teeth of Lanzhousaurus Lanzhousaurus (jaw and teeth).png
Jaw and teeth of Lanzhousaurus

The genus has been described as having "astonishingly huge teeth", among the largest for any herbivorous creature ever, which indicate it was a styracosternan iguanodont. The mandible, longer than one meter, suggests a very large size for the animal. Tooth enamel of this dinosaur was growing very rapidly. [3]

Classification

Life restoration Lanzhousaurus UDL.png
Life restoration

In their 2020 reassessment of the hadrosauromorph Orthomerus , Madzia, Jagt & Mulder ran phylogenetic analyses of Iguanodontia. In their analyses, Lanzhousaurus was recovered as a non-hadrosauriform styracosternan member of the Ankylopollexia, similar to the 2005 description by You, Ji & Li. The results of their phylogenetic analyses are shown in the cladogram below: [4] [1]

Ankylopollexia

Related Research Articles

<span class="mw-page-title-main">Ornithischia</span> Extinct clade of dinosaurs

Ornithischia is an extinct clade of mainly herbivorous dinosaurs characterized by a pelvic structure superficially similar to that of birds. The name Ornithischia, or "bird-hipped", reflects this similarity and is derived from the Greek stem ornith- (ὀρνιθ-), meaning "bird", and ischion (ἴσχιον), meaning "hip". However, birds are only distantly related to this group as birds are theropod dinosaurs. Ornithischians with well known anatomical adaptations include the ceratopsians or "horn-faced" dinosaurs, the pachycephalosaurs or "thick-headed" dinosaurs, the armored dinosaurs (Thyreophora) such as stegosaurs and ankylosaurs, and the ornithopods. There is strong evidence that certain groups of ornithischians lived in herds, often segregated by age group, with juveniles forming their own flocks separate from adults. Some were at least partially covered in filamentous pelts, and there is much debate over whether these filaments found in specimens of Tianyulong, Psittacosaurus, and Kulindadromeus may have been primitive feathers.

<span class="mw-page-title-main">Hypsilophodontidae</span> Extinct family of dinosaurs

Hypsilophodontidae is a traditionally used family of ornithopod dinosaurs, generally considered invalid today. It historically included many small bodied bipedal neornithischian taxa from around the world, and spanning from the Middle Jurassic until the Late Cretaceous. This inclusive status was supported by some phylogenetic analyses from the 1990s and mid 2000s, although there have also been many finding that the family is an unnatural grouping which should only include the type genus, Hypsilophodon, with the other genera being within clades like Thescelosauridae and Elasmaria. A 2014 analysis by Norman recovered a grouping of Hypsilophodon, Rhabdodontidae and Tenontosaurus, which he referred to as Hypsilophodontia. All other analyses from around the same time have instead found these latter taxa to be within Iguanodontia.

<i>Shantungosaurus</i> Genus of ornithopod dinosaurs

Shantungosaurus is a genus of very large saurolophine hadrosaurid dinosaur found in the Late Cretaceous Wangshi Group of the Shandong Peninsula in China, containing a single species, Shantungosaurus giganteus. The stratigraphic interval of Shantungosaurus ranges from the top of the Xingezhuang Formation to the middle of the Hongtuya Formation, middle to late Campanian in age. Shantungosaurus is so far the largest hadrosauroid taxon in the world, with size estimates around 15–17 metres (49–56 ft) in length and 13–16 metric tons in body mass.

<i>Agilisaurus</i> Extinct genus of dinosaurs

Agilisaurus is a genus of ornithischian dinosaur from the Middle Jurassic Period of what is now eastern Asia. It was about 3.5–4 ft long, 2 ft in height and 40 kg in weight.

<i>Fukuisaurus</i> Extinct genus of dinosaurs

Fukuisaurus is a genus of herbivorous ornithopod dinosaur that lived during the Early Cretaceous in what is now Japan. The type species is F. tetoriensis, which was named and described in 2003.

<i>Changchunsaurus</i> Extinct genus of dinosaurs

Changchunsaurus is an extinct genus of small herbivorous dinosaur from Early Cretaceous deposits of Gongzhuling, Jilin, China. It is the first named dinosaur genus from Jilin.

<i>Lurdusaurus</i> Extinct genus of dinosaurs

Lurdusaurus is a genus of massive and unusually shaped iguanodont dinosaur from the Elrhaz Formation in Niger. It contains one species, L. arenatus. The formation dates to the Early Cretaceous, roughly 112 million years ago. Lurdusaurus has a highly atypical body plan for an iguanodont, with a small skull, long neck, rotund torso, and powerful forelimbs and claws, somewhat reminiscent of a ground sloth. Its metacarpals are fused and reinforced into a large block, and the thumb spike is remarkably enormous. These would have allowed the hand to have functioned almost like a ball-and-chain flail. Lurdusaurus is estimated to have been 7–9 m (23–30 ft) long and 2 m high when on all-fours, but its stomach would have been only 70 cm off the ground. It may have weighed 2.5–5.5 t, conspicuously heavy for an iguanodontid this size.

<i>Probactrosaurus</i> Extinct genus of dinosaurs

Probactrosaurus is an early herbivorous hadrosauroid iguanodont dinosaur. It lived in China during the Early Cretaceous period.

Siluosaurus is a genus of ornithischian dinosaur from the Barremian-Albian-age Lower Cretaceous Xinminbao Group of Gansu, China. It is based on the specimen IVPP V.11117 (1-2), which consists of two teeth. It is an obscure genus, with no papers doing more than mentioning it since it was described in 1997. The type species is S. zhanggiani.

<i>Orthomerus</i> Extinct genus of dinosaurs

Orthomerus is a genus of dubious hadrosaurid dinosaur from the Late Cretaceous of the Netherlands. It is today an obscure genus, but in the past was conflated with the much better known Telmatosaurus.

<span class="mw-page-title-main">Dryosauridae</span> Extinct family of dinosaurs

Dryosauridae was a family of primitive iguanodonts, first proposed by Milner & Norman in 1984. They are known from Middle Jurassic to Early Cretaceous rocks of Africa, Europe, and North America.

<i>Suzhousaurus</i> Extinct genus of dinosaurs

Suzhousaurus is a genus of large therizinosauroid dinosaur from the Early Cretaceous of China. The genus is known from two specimens discovered on the Xiagou Formation and Zhonggou Formation—which are situated in the Xinminbao Group. These findings were made during field-works in 1999 and 2004. Though Suzhousaurus is known from these two specimens, an earlier named and described therizinosauroid from the adjacent basin, "Nanshiungosaurus" bohlini, may be synonymous with the former. However, Suzhousaurus can not be compared to this species due to non-overlapping material and the loss of the same. Moreover, this synonymy will result in Suzhousaurus bohlini with "N". bohlini having priority.

<i>Daxiatitan</i> Extinct genus of dinosaurs

Daxiatitan is a genus of sauropod dinosaur known from the Lower Cretaceous of Gansu, China. Its type and only species is Daxiatitan binglingi. It is known from a single partial skeleton consisting of most of the neck and back vertebrae, two tail vertebrae, a shoulder blade, and a thigh bone. At the time of its discovery in 2008, Daxiatitan was regarded as potentially the largest known dinosaur from China.

The Hekou Group is a geological group in Gansu Province, China. It is Early Cretaceous in age. Many dinosaur fossils have been recovered from the Hekou Group, including iguanodonts, large sauropods, and armored dinosaurs. Fossil eggs are rare, but one oogenus, Polyclonoolithus, was discovered in the Hekou Group. Extensive fossil tracks belonging to pterosaurs and dinosaurs have also been described. The group spans the Valanginian to Albian and can be subdivided into four formations.

<i>Ruyangosaurus</i> Extinct genus of dinosaurs

Ruyangosaurus is a genus of titanosauriform sauropod dinosaur recovered from the Early Cretaceous Haoling Formation of China. The type species is R. giganteus, described in 2009 by Lü Junchang et al.

<i>Xiongguanlong</i> Extinct genus of dinosaurs

Xiongguanlong is an extinct genus of tyrannosauroid theropod from the Early Cretaceous period of what is now China. The type and only species is X. baimoensis. The generic name comes from Jiayuguan City and the Mandarin word "long" which means dragon. The specific epithet, "baimoensis" is a latinization of the Mandarin word for "white ghost" in reference to one of the geological features of the type locality.

<span class="mw-page-title-main">Elasmaria</span> Extinct clade of dinosaurs

Elasmaria is a clade of ornithopods known from Cretaceous deposits in South America, Antarctica, and Australia that contains many bipedal ornithopods that were previously considered "hypsilophodonts".

<span class="mw-page-title-main">Hadrosauromorpha</span> Extinct clade of dinosaurs

Hadrosauromorpha is a clade of iguanodontian ornithopods, defined in 2014 by David B. Norman to divide Hadrosauroidea into the basal taxa with compressed manual bones and a pollex, and the derived taxa that lack them. The clade is defined as all the taxa closer to Edmontosaurus regalis than Probactrosaurus gobiensis. This results in different taxon inclusion depending on the analysis.

Celina A. Suarez is an American geologist. She is known for her research on using trace element and stable isotope geochemistry of fossil vertebrates and invertebrates to understand paleoecology, paleoclimatology, and taphonomy of ancient terrestrial ecosystems. She is an associate profession in the Department of Geosciences at the University of Arkansas. The dinosaur Geminiraptor suarezarum is named after Suarez and her twin sister, Marnia Suarez, co-discovers of the site on which it was found.

References

  1. 1 2 You, Hailu; Ji, Qiang; Li, Daqing (2005). "Lanzhousaurus magnidens gen. et sp. nov. from Gansu Province, China: the largest-toothed herbivorous dinosaur in the world" [中国甘肃发现世界上最大牙齿的植食性恐龙:巨齿兰州龙(新属、新种)]. Geological Bulletin of China. 24 (9): 785–794. ISSN   1671-2552.
  2. Paul, Gregory S. (2016). The Princeton Field Guide to Dinosaurs (2nd ed.). New Jersey: Princeton University Press. p. 319.
  3. Celina A. Suarez, Hai-Lu You, Marina B. Suarez, Da-Qing Li & J. B. Trieschmann (2017). Stable Isotopes Reveal Rapid Enamel Elongation (Amelogenesis) Rates for the Early Cretaceous Iguanodontian Dinosaur Lanzhousaurus magnidens. Scientific Reports7, Article number: 15319 (2017). doi:10.1038/s41598-017-15653-6
  4. Madzia, Daniel; Jagt, John W. M.; Mulder, Eric W. A. (2020-04-01). "Osteology, phylogenetic affinities and taxonomic status of the enigmatic late Maastrichtian ornithopod taxon Orthomerus dolloi (Dinosauria, Ornithischia)". Cretaceous Research . 108: 104334. Bibcode:2020CrRes.10804334M. doi: 10.1016/j.cretres.2019.104334 . ISSN   0195-6671.