'' is a Dinosaur fossile from the the Late Cretaceous of Madagascar .
It is the subject of some controversy as to its proper taxonomic position--whether it is a member of the Crown Clade Aves or a closely related Dromaeosaur . The presence of what have been interpreted to be Quill Knobs on its Ulna led initially to its inclusion among the birds; however, the rest of the skeleton is rather typically dromaeosaurid in its attributes. Given the extremely close affinities between primitive birds and their dromaeosaur cousins, along with the possibility that flight may have developed and been lost multiple times among these groups, it may be impossible to place ''Rahonavis'' firmly among or outside the birds. At this point, the controversies regarding the relative relationships among birds, dromaeosaurs, and Troodontids are numerous and change with each new feathered fossil discovery. Makovicky et al. (2005) found ''Rahonavis'' to be closely related to the South American dromaeosaurs ''Unenlagia'' and ''Buitreraptor'', and thus a member of the subfamily Unenlagiinae (this is the position used in the taxobox here). It may actually be closer to '' Archaeopteryx '', and thus a member of Class Aves and Order Archaeopterygiformes .
What is clear from the remains is that the living ''Rahonavis'' was a small predator, about the size of '' Archaeopteryx '' with the typical '' Velociraptor ''-like raised sickle claw on the second toe. Its discoverers (Forster, Sampson, Chiappe, and Krause, 1998) initially named it '' Rahona '' but changed the name after discovering that the name ''Rahona'' was already assigned to a butterfly. Although numerous artists' reconstructions of ''Rahonavis'' show it in flight, it is not clear that it could fly; there has even been some doubt that the forearm material, which includes the quill knobs, belongs with the rest of the skeleton, although its discoverers are convinced that it does.
- Makovicky, Apesteguía and Agnolín (2005). "The earliest dromaeosaurid theropod from South America". ''Nature''. 437, 1007-1011.
- Forster, Sampson, Chiappe and Krause (1998). "The Theropod Ancestry of Birds: New Evidence from the Late Cretaceous of Madagascar". ''Science''. 279: 1915-1919.
- Forster and O'Conner (2000). "The avifauna of the Upper Cretaceous Maevarano Formation, Madagascar". ''JVP''. 20(3), 41A-42A.
- Schweitzer, Watt, Avci, Forster, Krause, Knapp, Rogers, Beech and Marshall (1999). "Keratin immunoreactivity in the Late Cretaceous bird Rahonavis ostromi". ''JVP''. 19(4), 712-722.
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