Pneumatoraptor is a genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of small, paravian dinosaur

Dinosaur

Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...

 that lived in Hungary

Hungary

Hungary , officially the Republic of Hungary , is a landlocked country in Central Europe. It is situated in the Carpathian Basin and is bordered by Slovakia to the north, Ukraine and Romania to the east, Serbia and Croatia to the south, Slovenia to the southwest and Austria to the west. The...

. It is known from a single complete left shoulder girdle (scapulocoracoid) found in the Csehbánya Formation

Csehbánya Formation

The Csehbánya Formation is a geological formation in Hungary whose strata date back to the Late Cretaceous. Dinosaur remains are among the fossils that have been recovered from the formation.-Vertebrate paleofauna:...

 of the Iharkút locality in the Bakony Mountains of western Hungary. This formation dates to the late Cretaceous

Cretaceous

The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...

 period (Santonian

Santonian

The Santonian is an age in the geologic timescale or a chronostratigraphic stage. It is a subdivision of the Late Cretaceous epoch or Upper Cretaceous series. It spans the time between 85.8 ± 0.7 mya and 83.5 ± 0.7 mya...

 age) about 85 million years ago.

The type species

Type species

In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...

 is Pneumatoraptor fodori, named for Géza Fodor, who provided funding for the dig. The genus name Pneumatoraptor refers to the pneumaticity of the bone, the hollow spaces that would have been filled with air sacs in life. The holotype

Holotype

A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...

 specimen is identified by the catalog number MTM

Hungarian Natural History Museum

The Hungarian Natural History Museum in Budapest, dating back to 1802, houses the largest natural history collections of Hungary and the region.-Foundation:...

 V.2008.38.1. and housed at the Hungarian Natural History Museum

Hungarian Natural History Museum

The Hungarian Natural History Museum in Budapest, dating back to 1802, houses the largest natural history collections of Hungary and the region.-Foundation:...

 in Budapest

Budapest

Budapest is the capital of Hungary. As the largest city of Hungary, it is the country's principal political, cultural, commercial, industrial, and transportation centre. In 2011, Budapest had 1,733,685 inhabitants, down from its 1989 peak of 2,113,645 due to suburbanization. The Budapest Commuter...

.

Description

Pneumatoraptor differs from other theropods in having a narrow shoulder blade that is nearly circular in cross section, as well as having a large opening in the bone to house a hollow air sac cavity. The bone is small, indicating that the animal was only about half the size of the related Sinornithosaurus

Sinornithosaurus

Sinornithosaurus is a genus of feathered dromaeosaurid dinosaur from the early Cretaceous Period of the Yixian Formation in what is now China. It was the fifth non–avian feathered dinosaur genus discovered by 1999...

or 0.73 m (2.2 ft). The shoulder girdle is L-shaped, showing it to be a member of the group Paraves

Paraves

Paraves is a branch-based clade containing birds and other closely related dinosaurs. The paravians include the Avialae, including Archaeopteryx and modern birds, and the Deinonychosauria, which includes the dromaeosaurids and troodontids....

, which also includes the dromaeosaurids

Dromaeosauridae

Dromaeosauridae is a family of bird-like theropod dinosaurs. They were small- to medium-sized feathered carnivores that flourished in the Cretaceous Period. The name Dromaeosauridae means 'running lizards', from Greek dromeus meaning 'runner' and sauros meaning 'lizard'...

, troodontids

Troodontidae

Troodontidae is a family of bird-like theropod dinosaurs. During most of the 20th century, troodontid fossils were few and scrappy and they have therefore been allied, at various times, with many dinosaurian lineages...

, and birds

Avialae

Avialae is a clade of dinosaurs containing their only living representatives, birds , and the most immediate extinct relatives of birds.-Competing definitions:...

. While the Pneumatoraptor remains are too incomplete to tell which, if any, of these specific groups it belongs to, many of the bones features are similar to dromaeosaurids.

Other paravian remains from the same formation may belong to Pneumatoraptor. These include isolated teeth, claws, tail vertebrae, and a partial lower leg bone (tibia).