''Zanabazar'' (meaning "

Zanabazar Öndör Gegeen Zanabazar, , , "High Saint Zanabazar"; 1635–1723 (born Eshidorji) was the sixteenth '' Jebtsundamba Khutuktu'' and the first ''Bogd Gegeen'' or supreme spiritual authority, of the Gelugpa (Yellow Hat) lineage of Tibetan Buddhism ...

") is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

of large troodontid

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

from the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the younger 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 ''creta'', the ...

Mongolia Mongolia; Mongolian script: , , ; lit. "Mongol Nation" or "State of Mongolia" () is a landlocked country in East Asia, bordered by Russia to the north and China to the south. It covers an area of , with a population of just 3.3 million, ...

. The genus was originally named by Rinchen Barsbold as the new species ''Saurornithoides junior''. In 2009 it was reclassified as its own genus and species, ''Zanabazar junior'', named after the first spiritual figurehead of

Tibetan buddhism Tibetan Buddhism (also referred to as Indo-Tibetan Buddhism, Lamaism, Lamaistic Buddhism, Himalayan Buddhism, and Northern Buddhism) is the form of Buddhism practiced in Tibet and Bhutan, where it is the dominant religion. It is also in majo ...

. The

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...

includes a

skull The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, the ...

vertebrae The spinal column, a defining synapomorphy shared by nearly all vertebrates,Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristic i ...

, and right

hindlimb A hindlimb or back limb is one of the paired articulated appendages (limbs) attached on the caudal ( posterior) end of a terrestrial tetrapod vertebrate's torso.http://www.merriam-webster.com/medical/hind%20limb, Merriam Webster Dictionary-Hindl ...

. ''Zanabazar'' was one of the largest and most

derived Derive may refer to: * Derive (computer algebra system), a commercial system made by Texas Instruments * ''Dérive'' (magazine), an Austrian science magazine on urbanism *Dérive, a psychogeographical concept See also * *Derivation (disambiguatio ...

troodontids.

History of discovery

The holotype was discovered in 1964 from the Bügiin Tsav locality of the Nemegt Formation and initially described by Rinchen Barsbold as a new species of ''

Saurornithoides ''Saurornithoides'' ( ) is a genus of troodontid maniraptoran dinosaur, which lived during the Late Cretaceous period. These creatures were predators, which could run fast on their hind legs and had excellent sight and hearing. The name is deriv ...

'' (''S. junior'') in 1974. This specimen, IGM 100/1, includes a nearly complete

and

braincase In human anatomy, the neurocranium, also known as the braincase, brainpan, or brain-pan is the upper and back part of the skull, which forms a protective case around the brain. In the human skull, the neurocranium includes the calvaria or skul ...

, part of the

pelvis The pelvis (plural pelves or pelvises) is the lower part of the trunk, between the abdomen and the thighs (sometimes also called pelvic region), together with its embedded skeleton (sometimes also called bony pelvis, or pelvic skeleton). The ...

, some tail

, and parts of the right

. In 2009 a review of the genus found that the support for ''S. junior'' in the same genus as ''S. mongoliensis'' was lacking.

Mark Norell Mark Allen Norell (born July 26, 1957) is an American paleontologist, acknowledged as one of the most important living vertebrate paleontologists. He is currently the chairman of paleontology and a research associate at the American Museum of Na ...

and colleagues re-classified the species in the new genus ''Zanabazar'', which they named in honor of

, the first spiritual head (Bogd Gegen) of

Tibetan Buddhism Tibetan Buddhism (also referred to as Indo-Tibetan Buddhism, Lamaism, Lamaistic Buddhism, Himalayan Buddhism, and Northern Buddhism) is the form of Buddhism practiced in Tibet and Bhutan, where it is the dominant religion. It is also in majo ...

in Outer Mongolia.

Description

''Zanabazar'' were large troodontids reaching in length and weighing . They are the largest known Asian troodontids, with a skull length of . At the time of the discovery of the genus, the only other troodontids that appeared to be larger than it were specimens from Alaska, however, '' Latenivenatrix'' are now considered the largest troodontids with in length. The preserved vertebrae in IGM 100/1 are completely fused, indicating that this individual was an adult at the time of death.

Classification

While originally included in ''Saurornithoides'', within the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Saurornithoididae Troodontidae is a clade of bird-like theropod dinosaurs. During most of the 20th century, troodontid fossils were few and incomplete and they have therefore been allied, at various times, with many dinosaurian lineages. More recent fossil discov ...

, ''Zanabazar'' is now thought to be a derived member of Troodontidae.

The cladogram below shows the phylogenetic position of ''Zanabazar'' among other troodontids following a 2014 analysis.

References

External links

Skull of IGM 100/1 at Digimorph
{{DEFAULTSORT:Zanabazar (Dinosaur) Late Cretaceous dinosaurs of Asia Troodontids Fossil taxa described in 2009 Taxa named by Mark Norell Taxa named by Rinchen Barsbold Nemegt fauna