''Monkonosaurus'' (meaning " Monkon lizard") is a dubious

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of herbivorous

stegosauria Stegosauria is a group of Herbivore, herbivorous ornithischian dinosaurs that lived during the Jurassic and early Cretaceous Period (geology), periods. Stegosaurian fossils have been found mostly in the Northern Hemisphere (North America, Europe a ...

dinosaur Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic Geological period, period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the #Evolutio ...

from the

Late Jurassic The Late Jurassic is the third Epoch (geology), epoch of the Jurassic Period, and it spans the geologic time scale, geologic time from 161.5 ± 1.0 to 143.1 ± 0.8 million years ago (Ma), which is preserved in Upper Jurassic stratum, strata.Owen ...

Early Cretaceous The Early Cretaceous (geochronology, geochronological name) or the Lower Cretaceous (chronostratigraphy, chronostratigraphic name) is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 143.1 ...

-aged Loe-ein Formation of

Tibet Tibet (; ''Böd''; ), or Greater Tibet, is a region in the western part of East Asia, covering much of the Tibetan Plateau and spanning about . It is the homeland of the Tibetan people. Also resident on the plateau are other ethnic groups s ...

(or the

Lura Formation of

China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...

). Some sources place it as alive during the Oxfordian -

Albian The Albian is both an age (geology), age of the geologic timescale and a stage (stratigraphy), stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early Cretaceous, Early/Lower Cretaceous epoch (geology), Epoch/s ...

stages, around 163 - 100 million years ago, although ''Monkonosaurus'' was probably only alive during the

(163 – 152.1 ± 0.9 million years ago), making it among the earliest known stegosaurs along with '' Chungkingosaurus'' and ''

Bashanosaurus ''Bashanosaurus'' (meaning "Bashan lizard") is an extinct genus of stegosaurian dinosaur from the Middle Jurassic (Bathonian age) Shaximiao Formation of Yunyang County, China. The genus contains a single species, ''Bashanosaurus primitivus'', k ...

''.

Discovery and naming

The genus was formalized by

Zhao Xijin Zhao Xijin (赵喜进; born c. 1935 died July 21, 2012) was a Chinese paleontologist notable for having named numerous dinosaurs. He was a professor at Beijing's Institute of Vertebrate Paleontology and Paleoanthropology. Biography Zhao Xijin was ...

in 1986.X. Zhao. 1986. eptilia ''Ching-kuo Ti Pao o Hsi'' 'The Cretaceous System of China. The Stratigraphy of China.''12:67-73 The generic name refers to

Markam County Markam County (; zh, s=芒康县) is a county under the jurisdiction of the Chamdo in the Tibet Autonomous Region, China, bordering the provinces of Sichuan to the east and Yunnan to the south. It is the easternmost county-level division of the ...

, also known as ''Monko''.Chao S., 1983. "Phylogeny and Evolutionary Stages of Dinosauria", ''Acta Palaeontologica Polonica'' 28 (1/2): 295-306 Zhao at the time gave neither a description, meaning the name remained a ''

nomen nudum In Taxonomy (biology), taxonomy, a ''nomen nudum'' ('naked name'; plural ''nomina nuda'') is a designation which looks exactly like a scientific name of an organism, and may have originally been intended to be one, but it has not been published ...

'', nor a

specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...

. The latter was provided in 1986 when the

type species In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the spe ...

''Monkonosaurus lawulacus'' was named, the epithet referring to the Lawushan, the Lawu mountains. The first description was provided in 1990 by

Dong Zhiming Dong Zhiming (Chinese language, Chinese: 董枝明, Pinyin: ''Dǒng Zhimíng''; January 1937 – 20 October 2024) was a Chinese vertebrate paleontologist formerly employed at the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) ...

.Dong, Z., 1990, "Stegosaurs of Asia", In: Carpenter, K. and Currie J. (eds.). ''Dinosaur Systematics''. Cambridge: Cambridge University Press. pp 255-268 The

holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...

, IVPP V 6975, was found in a layer of the Loe-ein Formation dating probably from the

, or from the

Lura Formation.Weishampel, David B; et al. (2004). "Dinosaur distribution (Early Cretaceous, Asia)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 563-570. . It consists of a partial skeleton lacking the skull. It contains a pelvis with sacrum, two vertebrae and three back plates. The fragmentary condition of this single skeleton places doubt on the validity of this genus, with some studies concluding it is a ''

nomen dubium In binomial nomenclature, a ''nomen dubium'' (Latin for "doubtful name", plural ''nomina dubia'') is a scientific name that is of unknown or doubtful application. Zoology In case of a ''nomen dubium,'' it may be impossible to determine whether a ...

''.

Description

''Monkonosaurus'' was about long when fully grown. The ilium has a length of 905 millimetres. The sacrum consists of five sacral vertebrae.

Classification

Zhao (1983) placed ''Monkonosaurus'' in the now obsolete Oligosacralosauroidea. Later researchers considered it an indeterminate member of the Stegosauridae.

References

{{Taxonbar, from=Q142593 Stegosauria Dinosaur genera Late Jurassic dinosaurs Fossil taxa described in 1990 Taxa named by Dong Zhiming Dinosaurs of China

Discovery and naming

Description

Classification

See also

References