''Daurlong'' (meaning " Daur dragon") is an extinct

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

dromaeosaurid Dromaeosauridae () is a family of feathered theropod dinosaurs. They were generally small to medium-sized feathered carnivores that flourished in the Cretaceous Period. The name Dromaeosauridae means 'running lizards', from Greek ('), meaning ...

dinosaur 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

Early Cretaceous The Early Cretaceous (geochronological name) or the Lower Cretaceous ( chronostratigraphic name), is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 145 Ma to 100.5 Ma. Geology Pr ...

(

Aptian The Aptian is an age in the geologic timescale or a stage in the stratigraphic column. It is a subdivision of the Early or Lower Cretaceous Epoch or Series and encompasses the time from 121.4 ± 1.0 Ma to 113.0 ± 1.0 Ma (million years ag ...

) Longjiang Formation of China. The genus contains a single species, ''D. wangi'', known from a nearly complete skeleton. ''Daurlong'' represents the first described occurrence of a preserved intestinal region in a theropod closely related to birds.

Discovery and naming

The ''Daurlong''

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 seve ...

specimen, IMMNH-PV00731, was found in sediments of the Longjiang Formation (Pigeon Hill locality) of

Morin Dawa Daur Autonomous Banner Morin Dawa Daur Autonomous Banner ( Mongolian: , ''Morin Dabaɣ-a Daɣur öbertegen jasaqu qosiɣu'', Mongolian Cyrillic: Мориндаваа Дагуур өөртөө засах хошуу; Dagur: Morin Dawaa Daor weerie ixkiewu guasei; ...

Inner Mongolia Inner Mongolia, officially the Inner Mongolia Autonomous Region, is an autonomous region of the People's Republic of China. Its border includes most of the length of China's border with the country of Mongolia. Inner Mongolia also accounts for ...

, China. This locality is dated to the

age of the

period. It consists of a nearly complete specimen of an individual, including a near-perfectly

articulated An articulated vehicle is a vehicle which has a permanent or semi-permanent pivot joint in its construction, allowing it to turn more sharply. There are many kinds, from heavy equipment to buses, trams and trains. Steam locomotives were sometim ...

skull. A partial

anuran A frog is any member of a diverse and largely carnivorous group of short-bodied, tailless amphibians composing the order Anura (ανοὐρά, literally ''without tail'' in Ancient Greek). The oldest fossil "proto-frog" '' Triadobatrachus'' i ...

skeleton was also preserved on the holotype

slab Slab or SLAB may refer to: Physical materials * Concrete slab, a flat concrete plate used in construction * Stone slab, a flat stone used in construction * Slab (casting), a length of metal * Slab (geology), that portion of a tectonic plate that i ...

. In 2022, ''Daurlong wangi'' was described as a new genus and species of dromaeosaurid theropod dinosaurs by Xuri Wang, Andrea Cau, Bin Guo, Feimin Ma, Gele Qing, and Yichuan Liu based on these remains. The generic name, "''Daurlong''", combines a reference to the Daur Nation with the Chinese "龙" ("lóng"), meaning "dragon." The specific name, "''wangi''", honors Wang Junyou, the director of the Inner Mongolia Museum of Natural History.

Description

''Daurlong'' was a mid-sized dromaeosaurid, about long. The preserved specimen is 85% the size of the ''

Tianyuraptor ''Tianyuraptor'' is a genus of short-armed dromaeosaurid dinosaur ('running lizard'; a type of small dinosaur considered to be closely related to birds) that lived during the Early Cretaceous, about 122 million years ago. Its remains have been ...

'' holotype, and 93% the size of the ''

Zhenyuanlong ''Zhenyuanlong'' (meaning ''"Zhenyuan's dragon"'', from Chinese Pinyin 龙/ 龍 lóng ''"dragon"'') is a genus of dromaeosaurid dinosaur from the Yixian Formation of Liaoning, China. It lived during the Aptian age of the early Cretaceous period ...

'' holotype. The skull is about 94% the length of the femur, and the forelimbs are less than 60% of the length of the hindlimbs. The specimen preserves

plumage Plumage ( "feather") is a layer of feathers that covers a bird and the pattern, colour, and arrangement of those feathers. The pattern and colours of plumage differ between species and subspecies and may vary with age classes. Within species, ...

along the back of the skull and neck, and the edges of the tail. The fossil does not include pennaceous

remiges Flight feathers (''Pennae volatus'') are the long, stiff, asymmetrically shaped, but symmetrically paired pennaceous feathers on the wings or tail of a bird; those on the wings are called remiges (), singular remex (), while those on the tai ...

and

rectrices Flight feathers (''Pennae volatus'') are the long, stiff, asymmetrically shaped, but symmetrically paired pennaceous feathers on the wings or tail of a bird; those on the wings are called remiges (), singular remex (), while those on the tai ...

, as in ''Zhenyuanlong''. A bluish layer preserved in the ''Daurlong'' specimen ribcage matches the intestinal tract seen in the ''

Scipionyx ''Scipionyx'' ( ) was a genus of theropod dinosaur from the Early Cretaceous of Italy, around 113 million years ago. There is only one fossil known of ''Scipionyx'', discovered in 1981 by an amateur paleontologist and brought to the attention ...

'' holotype.

Classification

In their

phylogenetic analyses In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...

, Wang ''et al''. (2022) recovered ''Daurlong'' as a member of the

Dromaeosauridae Dromaeosauridae () is a family of feathered theropod dinosaurs. They were generally small to medium-sized feathered carnivores that flourished in the Cretaceous Period. The name Dromaeosauridae means 'running lizards', from Greek ('), meaning ...

, in a clade containing ''Tianyuraptor'' and ''Zhenyuanlong''. The

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

below displays the results of their phylogenetic analyses.

References

{{Taxonbar, from=Q115287977 Dromaeosaurs Aptian life Cretaceous China Fossils of China Fossil taxa described in 2022