''Khaan'' (; from Mongol 'lord') is an extinct genus of

oviraptorid Oviraptoridae is a group of bird-like, herbivorous and omnivorous maniraptoran dinosaurs. Oviraptorids are characterized by their toothless, parrot-like beaks and, in some cases, elaborate crests. They were generally small, measuring between one ...

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 ...

known from remains found in the

Djadochta Formation The Djadochta formation (sometimes transcribed and also known as Djadokhta, Djadokata, or Dzhadokhtskaya) is a highly fossiliferous geological formation in Central Asia, Gobi Desert, dating from the Late Cretaceous period, about 75 million ...

Mongolia Mongolia is a landlocked country in East Asia, bordered by Russia to the north and China to the south and southeast. It covers an area of , with a population of 3.5 million, making it the world's List of countries and dependencies by po ...

, dating to the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the more recent of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''cre ...

(

Campanian The Campanian is the fifth of six ages of the Late Cretaceous epoch on the geologic timescale of the International Commission on Stratigraphy (ICS). In chronostratigraphy, it is the fifth of six stages in the Upper Cretaceous Series. Campa ...

, 75-71

million years ago Million years ago, abbreviated as Mya, Myr (megayear) or Ma (megaannum), is a unit of time equal to (i.e. years), or approximately 31.6 teraseconds. Usage Myr is in common use in fields such as Earth science and cosmology. Myr is also used w ...

Description

''Khaan'' did not differ much from other oviraptorids. At first, its remains were assigned to " Ingenia", but the ''Khaan'' manual structure, lacking the expansion of the upper third

metacarpal In human anatomy, the metacarpal bones or metacarpus, also known as the "palm bones", are the appendicular bones that form the intermediate part of the hand between the phalanges (fingers) and the carpal bones ( wrist bones), which articulate ...

, was considered to differ sufficiently from that of "Ingenia" for it to be assigned to its own genus. The oviraptorid diet is disputed, with plants and molluscs having been suggested. Like other oviraptorids, ''Khaan'' was probably at least partially a meat eater, feeding on small

vertebrate Vertebrates () are animals with a vertebral column (backbone or spine), and a cranium, or skull. The vertebral column surrounds and protects the spinal cord, while the cranium protects the brain. The vertebrates make up the subphylum Vertebra ...

s like

mammal A mammal () is a vertebrate animal of the Class (biology), class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three ...

lizard Lizard is the common name used for all Squamata, squamate reptiles other than snakes (and to a lesser extent amphisbaenians), encompassing over 7,000 species, ranging across all continents except Antarctica, as well as most Island#Oceanic isla ...

s and possibly other small dinosaurs. It was also probably feathered.

Discovery

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 ...

''Khaan mckennai'' was named by James M. Clark ''et al.'' in 2001. The genus name is derived from

Mongol Mongols are an East Asian ethnic group native to Mongolia, China (Inner Mongolia and other 11 autonomous territories), as well as the republics of Buryatia and Kalmykia in Russia. The Mongols are the principal member of the large family of M ...

''khaan'', "lord" or "ruler". The

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 ...

honours the

paleontologist Paleontology, also spelled as palaeontology or palæontology, is the scientific study of the life of the past, mainly but not exclusively through the study of fossils. Paleontologists use fossils as a means to classify organisms, measure geolo ...

Malcolm Carnegie McKenna Malcolm Carnegie McKenna (1930–2008) was an American paleontologist and author on the subject. Paleontologist McKenna began his paleontology career at the Webb School of California (grades 9-12) in Claremont, California, under noted paleontolo ...

. 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 ...

IGM 100/1127 consists of an almost complete skeleton found together with another specimen, IGM 100/1002. Together they were informally referred to as "Romeo and Juliet". These individuals are about four feet long. A third, considerably larger, specimen, IGM 100/973, was referred to the species.

Classification

''Khaan'' was by Clark assigned to the

Oviraptoridae Oviraptoridae is a group of bird-like, herbivorous and omnivorous maniraptoran dinosaurs. Oviraptorids are characterized by their toothless, parrot-like beaks and, in some cases, elaborate crests. They were generally small, measuring between one ...

. Among oviraptorids, it was probably more closely related to ''

Conchoraptor ''Conchoraptor'' (meaning "conch plunderer") is a genus of oviraptorid dinosaurs that lived in Asia during the Late Cretaceous epoch, about 70 million years ago. It is known from the Barun Goyot and Nemegt Formation, Nemegt formations of Mongolia ...

''. The

cladogram A cladogram (from Greek language, Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an Phylogenetic tree, evolutionary tree because it does not s ...

below follows an analysis by Fanti ''et al.'', 2012.

Paleobiology

According to a 2014 study published in

Nature Nature is an inherent character or constitution, particularly of the Ecosphere (planetary), ecosphere or the universe as a whole. In this general sense nature refers to the Scientific law, laws, elements and phenomenon, phenomena of the physic ...

, ''Khaan'' was possibly

sexually dimorphic Sexual dimorphism is the condition where sexes of the same species exhibit different Morphology (biology), morphological characteristics, including characteristics not directly involved in reproduction. The condition occurs in most dioecy, di ...

. Two specimens, the holotype MPC-D 100/1127 and referred specimen MPC-D 100/1002, were analyzed, the dimorphic feature being in the anterior

chevrons Chevron (often relating to V-shaped patterns) may refer to: Science and technology * Chevron (aerospace), sawtooth patterns on some jet engines * Chevron (anatomy), a bone * '' Eulithis testata'', a moth * Chevron (geology), a fold in rock la ...

. Both specimens were of the same size and build, and thus were likely the same age, ruling out

ontogeny Ontogeny (also ontogenesis) is the origination and development of an organism (both physical and psychological, e.g., moral development), usually from the time of fertilization of the ovum, egg to adult. The term can also be used to refer to t ...

. In MPC-D 100/1127, the anterior chevrons showed great similarity to those of other theropods, with no great expansion on the distal end. However, in the other individual, the chevrons had a "heel"-like expansion above the distal end, which increased in size along the sequence. The study ruled out a possibly pathologic explanation, finding sexual dimorphism to have more support. It was thought that the reduced spines were a female characteristic, because they would increase space for laying eggs. Also, the larger spines could be for male muscle attachments, which would support a tail fan. A 2022 study of the bite force of ''Khaan'' and comparisons with other oviraptorosaurs such as ''

Incisivosaurus ''Incisivosaurus'' ("incisor lizard") is a genus of small, probably herbivorous theropod dinosaurs from the early Cretaceous Period of what is now the People's Republic of China. The first specimen to be described (by Xu ''et al.'' in 2002), IVPP ...

'', ''

Citipati ''Citipati'' (; meaning "funeral pyre lord") is a genus of oviraptorid dinosaur that lived in Asia during the Late Cretaceous Period (geology), period, about 75 million to 71 million years ago. It is mainly known from the Ukhaa Tolgod locality ...

'', and ''

'' suggests that ''Khaan'' had a very strong bite force. The moderate jaw gape seen in oviraptorosaurs is indicative of herbivory in the majority of the group, but it is clear they were likely feeding on much tougher or more types of vegetation than other herbivorous theropods in their environment, such as ornithomimosaurs and therizinosaurs were able to. The examinations suggest oviraptorosaurs may have been powerful-biting generalists or specialists that partook of niche partitioning both in body size and cranial function.

References

{{Taxonbar, from=Q135295 Oviraptoridae Dinosaur genera Campanian dinosaurs Djadochta Formation Fossil taxa described in 2001 Taxa named by Mark Norell Taxa named by Rinchen Barsbold Dinosaurs of Mongolia

Description

Discovery

Classification

Paleobiology

See also

References