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A Brief Look at Wukongopterus
So, with all respect to parties here, I would like to insert a comment on this
more robustly than I did before. It is true that there may be crushing or
distortion involved that would discriminate Wukognopterus lii as an abberant
Darwinopterus modularis, or at least a Wukongopterus lii as a new species of
Darwinopterus, D. lii. However, some details preclude the argument that
distortion alone is responsible for their dismimilarity.
1. Maxillary dentition appears to be generally and consistently isoceletic,
with minimal recurvature; it is only minorly important to note that this
denition appears labiolingually compressed and, where it is recurved, generally
ziphodont in form. In *D. modularis*, the dentition is consistently recurved
and apparently conodont.
2. Dentition almost consistently has an average CBL of 2 or so, less than 3,
while in *D. modularis* this appears to be more consistently 4 or greater.
3. Clustering of mesial dentition occurs with diminishing size of teeth in *W.
lii* but not in *D. modularis*.
4. The mandibular postdentary ramus appears to be greater than 4x deeper than
the corresponding depth of the jugal, while in *D. modularis* this factor is
less than 3. (The relevant valude of this is discriminant only to these taxa
for the most part, as the jugal takes on substantial variation in other clades
so I would not evaluate this feature relative to other pterosaurs; nonetheless,
it discriminates the provided specimens).
Moving away from the skull, one can postulate postcranial differences, but
these seem to be very minor and proportional, with one exception:
5. PdV-2, the elongated spur of the fifth toe, is L-shaped in *W. lii*, but
this element is shallowly curved in *D. modularis* and in virtually every other
pterosaur that possesses one of these bones.
It should be noted that, without adding details that might discriminate the
taxa, a given matrix may not yield up distinctions between the two, such that
when there are distinctions, the taxa would be clustered together, yet still
distinct (as these are). However, adding in dentition morphology characters
that can discriminate these taxa (in which *Wukongopterus* teeth resemble those
of istiodactylids while *Darwinopterus* teeth resemble those of general
"rhamphorhynchoids") should produce a more complex picture.
The proposition that the mandible has undergone enough distortion to compensate
for the extreme depth relative to other bones in *Wukongopterus* seems
untenable, as it would be the only apparent element to have undergone this
process, being adjacent to other undistorted elements of the skull and
postcrania, while it at the same time has retained almost all of its apparent
surface integrity and without distortion relative to other bones (complete
occlusion with the upper jaw), showing no fractures or breaks aside from that
which separates the mesial and distal portions of the jaw on the slab;
*Darwinopterus* specimens are consistent, based only on the type and referred
material in Lü et al., with respect to their depth, yet show worse preservation
in some areas (the type) than *Wukongopterus*'s type specimen.
I should note at this point that I consider my cursory examination incomplete,
and I lack the resources to test the matrices myself through the act of
encoding the dentition, mandibular proportions, etc. in order to test the
argument above. I should be able to rectify this at some point, but not now. In
addition, it is my opinion that these two taxa are distinct, at least at the
species level. And because I am not a hypocrite and would like to affirm my
previous stances on nomenclature, if the species as originally named stand,
then so should their "generic" containers, and as such I would regard *W. lii*
and *Wukongopterus lii* as being the same essential taxon label; this means I
would treat *Darwinopterus modularis* and *Wukongopterus lii* as distinct taxa,
even if they were found as each others' closest sister taxa in every
Jaime A. Headden
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