Belongs within: Maniraptora.
The Dromaeosauridae included some of the most hypercarnivorous of all maniraptoran coelurosaurs, including such famed taxa as Deinonychus antirrhopus and Velociraptor mongoliensis. They varied in size from members of the genus Utahraptor, estimated to be well over five metres in length, to species of Microraptor with lengths less than one metre (among the smallest known non-avian dinosaurs). The dromaeosaurs are most famous for the development of a large hyperextendable sickle claw on digit II of the foot, most commonly presumed to have played some part in the subduing and killing of prey animals. Well-preserved specimens of dromaeosaurids (particularly of Microraptor species) have demonstrated the presence of extensive feather covering; in Microraptor, elongate feathers were present on the legs as well as on the arms, and may have served an aerodynamic function.
The majority of dromaeosaurid species are known from the Cretaceous of Eurasia and North America. However, the family also includes a basal clade of Unenlagia and related taxa from South America.
Characters (from Norell & Makovicky 2004): Frontals short, T-shaped, with sinusoidal edge demarcating rostral boundary of supratemporal fenestra; squamosal with caudolateral overhanging shelf; quadrate bearing lateral process contacting quadratojugal dorsally above enlarged quadrate foramen; dorsal vertebrae bearing raised, stalklike parapophyses; digit II modified, raptorial; caudal vertebrae with chevrons and prezygapophyses elongate, spanning several vertebrae; coracoid bearing subglenoid fossa.
<==Dromaeosauridae |--Mahakala omnogovaeGC13, LC09 `--+--UnenlagiinaeLC09 | |--Austroraptor cabazaiGC13, LC09 | |--Neuquenraptor Novas & Pol 2005GC13, NP05 | | `--*N. argentinus Novas & Pol 2005NP05 | |--Buitreraptor Makovicky 2005GC13, D07 | | `--B. gonzalezorumHH09 | `--Unenlagia Novas & Puerta 1997GC13, NM04 | |--U. comahuensis Novas & Puerta 1997NM04 | `--U. paynemiliCG13 `--+--Microraptorinae [Microraptoria]LC09 | | i. s.: Hesperonychus Longrich & Currie 2009LC09 | | `--*H. elizabethae Longrich & Currie 2009LC09 | |--Shanag ashileGC13, LC09 [=Sinornithosaurus ashileP10] | `--+--Graciliraptor Xu & Wang 2004GC13, D07 | `--+--Microraptor Xu, Zhou & Wang 2000GC13, NM04 [incl. Cryptovolans Cxerkas, Zhang et al. 2002D07] | | |--*M. zhaoianus Xu, Zhou & Wang 2000LC09, NM04 (see below for synonymy) | | `--M. gui Xu, Zhou et al. 2003LC09, NM04 | `--Sinornithosaurus Xu, Wang & Wu 1999GC13, NM04 | |--S. lujiatunensis [=Graciliraptor lujiatunensis]P10 | `--S. millenii Xu, Wang & Wu 1999NM04 [incl. S. haoinaP10] `--EudromaeosauriaLC09 |--SaurornitholestinaeLC09 | |--Atrociraptor marshalliLC09, HH09 | |--Saurornitholestes Sues 1978LC09, NM04 | | `--S. langstoni Sues 1978NM04 [=Velociraptor langstoniP88] | `--+--Tianyuraptor ostromiGC13, P10 | `--Bambiraptor Burnham, Derstler et al. 2000LC09, NM04 | `--B. feinbergorum Burnham, Derstler et al. 2000NM04 `--+--Deinonychus Ostrom 1969LC09, NM04 | `-*D. antirrhopus Ostrom 1969O69 [=Velociraptor antirrhopusP88] `--+--VelociraptorinaeLC09 | |--+--Tsaagan mangasLC09, XT07 [=Velociraptor mangasP10] | | `--Adasaurus Barsbold 1983LC09, NM04 | | `--A. mongoliensis Barsbold 1983NM04 | `--+--Velociraptor Osborn 1924LC09, NM04 | | `--V. mongoliensis Osborn 1924NM04 [incl. V. osmolskaeP10] | `--Itemirus Kurzanov 1976LC09, H04 [Itemiridae] | `--I. medullaris Kurzanov 1976H04 `--DromaeosaurinaeLC09 |--Achillobator Perle, Norell & Clark 1999HH09, NM04 | `--A. giganticus Perle, Norell & Clark 1999NM04 `--+--Dromaeosaurus Matthew & Brown 1922GC13, NM04 | |--D. albertensis Matthew & Brown 1922NM04 | `--D. gracilis (Marsh 1888) (n. d.) [=Coelurus gracilis]O69 `--Utahraptor Kirkland, Burge & Gaston 1993GC13, NM04 |--U. ostrommaysi Kirkland, Burge & Gaston 1993NM04 `--U. spielbergiD07 Dromaeosauridae incertae sedis: Pyroraptor Allain & Taquet 2000NM04 `--P. olympius Allain & Taquet 2000NM04 Variraptor Le Loeuff & Buffetaut 1998NM04 `--V. mechinorum Le Loeuff & Buffetaut 1998NM04 Hulsanpes Osmólska 1982NM04 `--H. perlei Osmólska 1982NM04 Phaedrolosaurus ilikensis Dong 1973 (n. d.)P88 Euronychodon Antunes & Sigogneau-Russell 1991NM04 |--E. asiaticus Nessov 1995NM04 `--E. portucalensis Antunes & Sigogneau-Russell 1991NM04 Ornithodesmus Seeley 1887NM04, W91 [Ornithodesmidae] `--*O. cluniculus Seeley 1887W91 Unquillosaurus Powell 1979NM04 `--U. ceibalii Powell 1979NM04 Palaeopteryx Jensen 1981NM04, U93 `--P. thomsoni Jensen 1981 (n. d.)NM04 Linheraptor exquisitusCV10 Pneumatoraptor fodoriCV10 Luanchuanraptor henanensisP10
*Microraptor zhaoianus Xu, Zhou & Wang 2000LC09, NM04 [=Sinornithosaurus zhaoianusP10; incl. Cryptovolans pauliSB04]
*Type species of generic name indicated
References
[CV10] Csiki, Z., M. Vremir, S. L. Brusatte & M. A. Norell. 2010. An aberrant island-dwelling theropod dinosaur from the Late Cretaceous of Romania. Proceedings of the National Academy of Sciences of the USA 107 (35): 15357–15361.
[D07] Dixon, D. 2007. The Complete Illustrated Encyclopedia of Dinosaurs & Prehistoric Creatures. Hermes House: London.
[GC13] Godefroit, P., A. Cau, Hu D.-Y., F. Escuillié, Wu W. & G. Dyke. 2013. A Jurassic avialan dinosaur from China resolves the early phylogenetic history of birds. Nature 498: 359–362.
[H04] Holtz, T. R. 2004. Tyrannosauroidea. In: Weishampel, D. B., P. Dodson & H. Osmólska (eds) The Dinosauria 2nd ed. pp. 111–136. University of California Press: Berkeley.
[HH09] Hu, D., L. Hou, L. Zhang & X. Xu. 2009. A pre-Archaeopteryx troodontid theropod from China with long feathers on the metatarsus. Nature 461: 640–643.
[LC09] Longrich, N. R., & P. J. Currie. 2009. A microraptorine (Dinosauria—Dromaeosauridae) from the Late Cretaceous of North America. Proceedings of the National Academy of Sciences of the USA 106 (3): 5002–5007.
[NM04] Norell, M. A., & P. J. Makovicky. 2004. Dromaeosauridae. In: Weishampel, D. B., P. Dodson & H. Osmólska (eds) The Dinosauria 2nd ed. pp. 196–209. University of California Press: Berkeley.
[NP05] Novas, F. E., & D. Pol. 2005. New evidence on deinonychosaurian dinosaurs from the Late Cretaceous of Patagonia. Nature 433: 858–861.
[O69] Ostrom, J. H. 1969. Osteology of Deinonychus antirrhopus, an unusual theropod from the Lower Cretaceous of Montana. Bulletin of the Peabody Museum of Natural History 30: 1–165.
[P88] Paul, G. S. 1988. Predatory Dinosaurs of the World: A Complete Illustrated Guide. Simon & Schuster: New York.
[P10] Paul, G. S. 2010. Dinosaurs: A Field Guide. A & C Black.
[SB04] Senter, P., R. Barsbold, B. B. Britt, & D. A. Burnham. 2004. Systematics and evolution of Dromaeosauridae (Dinosauria, Theropoda). Bulletin of Gunma Museum of Natural History 8: 1–20.
[U93] Unwin, D. M. 1993. Aves. In: Benton, M. J. (ed.) The Fossil Record 2 pp. 717–737. Chapman & Hall: London.
[W91] Wellnhofer, P. 1991. The Illustrated Encyclopedia of Pterosaurs. Salamander Books: London (reprinted 2000. In: Norman, D., & P. Wellnhofer. The Illustrated Encyclopedia of Dinosaurs. Salamander Books).
[XT07] Xu, X., Q. Tan, J. Wang, X. Zhao & L. Tan. 2007. A gigantic bird-like dinosaur from the Late Cretaceous of China. Nature 447: 844–847.