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I recieved Dinosaurs of the Air today, and it looks
terrific. Will take a while to read all 409 pages, but one thing that
should be mentioned is the creation of several new taxa.
Avepoda- An apomorphy-based taxon defined as all
theropods with metatarsal I not contacting the tarsus, or that descended from
such taxa (must include Neotheropoda). This is what's been called
"Eutheropoda" on the list, though I don't know if the latter name has been
published. Basically it's Coelophysoidea + Neotheropoda, excluding
Guaibasaurus, herrerasaurids and such. Paul is sure to note this should
not be confused with Novas' (1991) Avipoda, which is similar to
Tetanurae.
Here I should note Paul uses Sereno's definition of
Neotheropoda (Coelophysis + Neornithes), while I and most others use Padian et
al.'s definition (Ceratosaurus + Neornithes, as originally concieved by
Bakker). So Paul's Neotheropoda and Avepoda are heterodefinitional
synonyms.
Averostra- An apomorphy-based taxon defined as all
theropods with a promaxillary fenestra, or that descended from such taxa (must
include Dromaeosauridae). This is placed identically to Padian et al.'s
Neotheropoda, but the issue is complicated by Dilophosaurus. Dilophosaurus
has a promaxillary fenestra (Witmer, 1997; Rauhut, 2000) and an uncertain
phylogenetic placement. Rauhut found it to be closer to ceratosaurs and
tetanurines than coelophysoids, while most others have found it to be a
coelophysoid. If the former is true, Averostra would be a useful clade
between Avepoda and Neotheropoda. If the latter is true, Averostra could
be a junior synonym of Avepoda (if coelophysids lost the promaxillary fenestra)
or a junior synonym of Neotheropoda (if Dilophosaurus developed it in
parallel).
Paul doesn't use Coelurosauria, Maniraptoriformes
or Maniraptora, for reasons I haven't read yet.
Avepectora- An apomorphy-based clade defined as all
taxa in which the majority of the distal edge of the coracoids articulate with
the anterior edge of the broad sternum at an angle of 45-90 degrees from
the midline, or that descended from such taxa (must include
Dromaeosauridae). This is equivalent to Maniraptoriformes in his
cladogram, though I'm personally unsure as to whether ornithomimosaurs
and alvarezsaurids show the derived pectoral condition. If not, it
could be a good name for the enigmosaur + paravian node. Unless we use
Dromavialae, Aviplumosa, Avipinna or Aviremigia. The first was not
officially defined though, and the last three were only suggested.
Avebrevicauda- An apomorphy-based clade defined as
all taxa with less than eleven free caudals, or that descended from such taxa
(must include Neornithes). Paul says this is different from Pygostylia
because Chatterjee's (1997) original use of this term excluded
Confuciusornis. Of course, Chiappe (2001) recently "recreated" this name
specifically for the clade Confuciusornis + Neornithes. I'll have to see
about Chatterjee's use, and how it affects the now standard use of the term
sensu Chiappe. Avebrevicauda might have a chance as the Sapeornis +
Neornithes clade, right below Pygostylia sensu Chiappe. But though
Sapeornis has a pygostyle, it is small and we only have two free caudal
vertebrae. So it may not have a proper avebrevicaudan tail.
I'll post more on the book in the future.
Great job Greg!
Mickey Mortimer
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