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Re: Coelurosauria

Jamie Stearns wrote-

I seem to have made some rather big mistakes on tyrannosaurs, so I'll have to redo much of the basal part of that clade. As for Dryptosaurus, how derived is it, exactly? I'm thinking probably somewhere near Alioramus and Appalachiosaurus at this point.

Carr et al. (2005) placed it basal to Appalachiosaurus. Holtz (2004) placed it basal to tyrannosaurids (including Appalachiosaurus in his topology) and Eotyrannus, and more derived than Bagaraatan, in a trichotomy with Stokesosaurus. Alectrosaurus and Alioramus were always more derived.

As for dromaeosaurs, yes, Deinonychus's skull is longer and lower in profile than Bambiraptor's. I'm still not certain as to the placement of Achillobator, though. It may be basal to Dromaeosauridae+Troodontidae.

I don't really know much about Adasaurus, as I can't seem to find any pictures of the skeleton. Utahraptor may have been placed too close to Deinonychus by mistake, as it seems the reconstruction I've seen was likely inspired by that monstrosity from Jurassic Park, at least judging from the shape of the skull.

The only illustrations of Adasaurus are its pelvis (Barsbold), second pedal digit (Barsbold), metatarsus (Senter et al.), and photographed mounted skeleton (online).
The only published Utahraptor cranial material is the premaxilla. The supposed lacrimal described turned out to be a Gastonia postorbital.

I've also heard that Utahraptor and Dromaeosaurus may form a clade and that Adasaurus may also be in that clade, but I'm not sure exactly what supports this. Something in the teeth?

It's possible. Also possible Adasaurus is outside the clade, or that Achillobator is a member as well.

Anyway, if this checks out, the tree would end up looking like this:

`---Achillobator
..`---Troodontidae
....`--+---Buitreraptor
......|...`---Unenlagia
......|....`---Rahonavis
......`--+---Utahraptor
........|...`---Adasaurus
........|.....`---Dromaeosaurus
........`--+---Deinonychus
..........|...`---Saurornitholestes
..........|.....`---Velociraptor
..........`---Bambiraptor
............`---Sinornithosaurus
..............`---Microraptor
................`---Archaeopteryx
..................`---All other birds


Then you'd have to explain all the dromaeosaur characters of Achillobator.

I have, however, heard rumors of Archaeopteryx actually being a more basal dromaeosaur or even a troodontid lately rather than the sister taxon to all other birds, as conventional wisdom would have it. How well-supported are these ideas, and are things like Microraptor actually closer to birds than Archaeopteryx is? 

Any of those ideas have some support.

Mickey Mortimer