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RE: New in CJES

Jaime Headden wrote-

  Zhou Z.-h., L. M. Chiappe & Zhang F.-c. 2005. Anatomy of the
   Early Cretaceous bird *Eoenantiornis buhleri* (Aves:
   Enantiornithes) from China. _Canadian Journal of Earth Sciences
   - Revue de canadienne sciences du Terre_ 42(7):1331-1338.

Mickey Mortimer can probably say more about this paper than I can.

Well, Zhou et al. provide a much-needed redescription of this specimen. They correct some statements of Hou et al. (1999). For instance, the sternum has typical enantiornithine posterolateral processes with expanded tips, as well as the smaller pointed posteromedial processes illustrated by Hou et al.. So the sternum isn't more primitive than Sinornis et al.. The teeth are contained in separate sockets, not a groove. This makes it more like other enantiornithines (Sinornis, Vescornis) and limits the presence of a groove to Ornithurae sensu Chiappe. There is a medial wall to the antorbital fossa, apparently containing a fenestra. The absence of an external mandibular fenestra (and much of the mandibular anatomy) cannot be established. Contra to either paper, there seem to be only ten cervicals, as the eleventh has an elongate rib. The number of sacrals is more than five, but cannot be stated to be 6-8 (contra Hou et al.). The coracoid appears more elongate than illustrated by Hou et al., so is not intermediate between other enantiornithines and Archaeopteryx. Basically, it's not obviously primitive like Hou et al. suggested, and is more similar to standard enantiornithines. Which makes sense, given basal taxa like Jibeinia have derived sternal and coracoid morphologies. I reconstructed the skull based on Zhou et al.'s figures-

http://students.washington.edu/eoraptor/Eoenantiornis%20skull2.jpg

Compare to Hou et al.'s reconstruction-

http://students.washington.edu/eoraptor/Eoenantiornis%20ori.jpg

Note the snout is longer, resembling other enantiornithines, and any resemblence to Caudipteryx or Omnivoropteryx (as suggested by Czerkas and Ji) is minimal.

Oh, and to answer David's question... no phylogenetic analysis is performed in the paper. By 'analysis', Zhou et al. merely mean their identification of characters synapomorphic of certain clades (Euenantiornithes) in Eoenantiornis.

Mickey Mortimer