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RE: Madagascan Flying Raptor is INDEED a Madagascan Flying Raptor...
Thomas R. Holtz, Jr. wrote:
Buitreraptor gonzalezorum, the most complete member of Unenlagiinae.
Placing it in an updated matrix, its pulls the above creatures
together into a clade at the base of Dromaeosauridae (especially if
Unenlagia and Neuquenraptor are the same taxon, as they
suggest). The remaining (Laurasian) clade contains Microraptorinae
(Microraptor + Sinornithosaurus), and a clade of classic
dromaeosaurids, divided into Dromaeosaurinae (Dromaeosaurus, Utahraptor,
Adasaurus, Saurornitholestes, and Achillobator) and
Velociraptorinae (Velociraptor, Deinonychus, IGM 100/1015).
The Supplementary Information has some interesting tidbits. It provides a
phylogenetic definition for Unenlagiinae ("all taxa closer to _Unenlagia
comahuensis_ than to _Velociraptor mongoliensis_"), and uses the
suprageneric taxon Microraptorinae, citing Senter et al. (2004). However,
Senter et al. (2004) did not erect or define the clade Microraptorinae (or
-idae) - they deliberately avoid using suffixes -idae and -inae, and instead
came up with Microraptoria. So I would assume that Microraptorinae
Makovicky et al. (2005) is equivalent to Microraptoria of Senter et al.
As for the proposed synonymy of _Unenlagia_ and _Nequenraptor_...
"Novas and Pol (2005) distinguished _Neuquenraptor_ from _Unenlagia_ based
on different femoral proportions, but the femur of _Neuquenraptor_ is
incomplete and lacks both proximal and distal articular ends, rendering any
estimates of proportions as tenuous. Examination of the preserved and
comparable features of the femora of both specimens revealed no substantial
differences between them, and also reveals that they are similar though not
identical in size. New material referred to _Unenlagia_ (Calvo et al.,
2004) includes pedal phalanges that are almost identical to Phalanx II-1 and
Phalanx II-3 of _Neuquenraptor_ in both size and proportions, although Calvo
et al. (2004) misidentified these bones as deriving from digit I and
illustrated Phalanx II-1 upside down. Although the co-occurrence and size
similarities between the few overlapping skeletal elements of
_Neuquenraptor_ and _Unenlagia_ appear to be compelling evidence for
possible synonymy, we recognize the need for more materials from the
Portezuelo Formation to test this hypothesis more rigorously."
Also, it appears that pelvic characters played a major role in pulling
_Rahonavis_, _Unenlagia_ and _Buitreraptor_ together; and the authors
suggest that the mobile scapulocoracoid joint was acquired independently in
_Rahonavis_ and ornithothoracine birds. Makovicky et al. (2005) also
mention possible unenlagiine material from northern Africa...
"Rauhut and Werner (1995) reported dromaeosaurid remains including pedal
phalanges and teeth from the Cenomanian Wadi Milk Fm. of Sudan. One of the
referred bones was a phalanx II-2 that is similar to unenlagines in having a
short, asymmetric heel (Rauhut, pers. com.). Although this is a
plesiomorphic trait and thus not indicative of relationships, it is
consistent with the presence of a possible unenlagiine in Africa. The
referred teeth were serrated, however, thus differinf [sic] from the
unserrated teeth of _Buitreraptor_. The pedal and dental materials were
found as isolated elements in several localities, so their association is
tenuous. Given the fragmentary and isolated nature of the Sudanese
material, and lack of data on the dentitions of _Unenlagia_ and _Rahonavis_,
it is impossible to refer any of the dromaeosaurid remains from Sudan to an
unenlagiine at present."
Some of that Mongolian dromaeosaur material (e.g., _Hulsanpes_) might be
worth a second look.
Like Novas' giant unenlagiine (shown at SVP last year), Buitreraptor has an
elongate (almost pterodactyloid-like) snout.
It's even possible (but at the moment entirely uncorroborated) that
_Unenlagia_ and _Rahonavis_ might have been toothless.
Flying dromaeosaurs?? What's next - oviraptorosaurs with pygostyes? Oh,
that's right...we already have them.