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Re: Three New Neoceratopsians (Bagaceratopsidae Described)



My final note on this is to mention some overlooked taxonomic issues (at least
on my part). First, Alifanov offers the following discussion of basal
neoceratopsians:

--+--Ceratopidae [sic]
   `--+--Protoceratopidae [sic]
      |   |--Protoceratops andrewsi
      |   |--Graciliceratops mongoliensis
      |   |--Leptoceratops gracilis
      |   |--Udanoceratops tschizhovi
      |   |--Achaeocerators [sic] oshimai
      |   `--Liaoceratops yanzigouensis
      `--Bagaceratopidae
          |--Bagaceratops rozhdestvenskyi
          |--Platyceratops tatarinovi
          |--Lamaceratops tereschenkoi
          `--Breviceratops kozlowskii

  This is accompanied by the topology of Sereno (2000) and Xu et al. (2002), so
the various and strongly supported topologies provided there are considered
secondary to this one. Alifanov questions the distinction of *Archaeoceratops*
[the above spelling represents an original _lapsus calami_ of the author] in the
original "family" Archaeoceratopsidae; Alifanov further questions the position
of *Liaoceratops* as a basal neoceratopsian on the basis of "the relatively
large maxillae, the presence of the preorbital depression, and participation of
the frontals in the formation of the upper orbital rim," all of which are
plesiomorphies in Ceratopsia anyway, which makes me wonder why they are
considered derived enough to preclude it from being more basal. Alifanov also
rejects the Leptoceratopsidae, sensu Makovicky (2000), without explanation, and
does not include *Protoceratops hellenikorhinus* (Lambert et al., 2001) in his
tree, though he discusses the history of the taxon briefly. Though Xu et al.
(2002) is mentioned, *Montanoceratops* appears to have been relegated to the
Ceratopsidae because "a number of researchers consider this genus to be close to
the Ceratopidae [sic] (=Ceratopsidae) (Sereno, 1986, 2000; Chinnery and
Weishampel, 1998)" (pg. 524). Alifanov also links *Microceratops sulcidens*
(Bohlin) to having dental features in common with *Breviceratops.*

  Lastly, a note on eggshell morphology: Three species of the ootaxon
*Protoceratopsidovum* are known from across the "Barungoyotian" of Mongolia,
with *P. fluxuosum* oospecies in the Barun Goyot linked to possible
bagaceratopids, *P. sincerum* oospecies from the Djadoktah linked to possible
protoceratopsids, and *P. minimum* oospecies is suggested as possibly belonging
to "*Udanoceratops*-like protoceratopids" [sic].

  This is my last original post on this subject ... I swear.

  Cheers,

  Jaime A. Headden

  Little steps are often the hardest to take. We are too used to making leaps in
the face of adversity, that a simple skip is so hard to do.  We should all learn
to walk soft, walk small, see the world around us rather than zoom by it.

  "Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)