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You may all remember when I wrote about Hulsanpes,
I provisionally excluded it from the enantiornithines because metatarsal IV is
not reduced. I did this because, as I said, this has only been confirmed
in American species and Concornis. Now I have Hou's paper on Chinese
fossil birds, so I can properly compare Hulsanpes with Asian
enantiornithines. It turns out my suspisions were warrented, as not all
enantiornithines have reduced fourth metatarsals, Cathayornis? caudatus,
Iberomesornis, Largirostrisornis and Sinornis being the exceptions.
Iberomesornis also has an unfused metatarsus, like Hulsanpes, while the other
three species have proximally fused metatarsi like other enntiornithines.
Unfortunately, further comparison is difficult as the pedes of Iberomesornis and
Sinornis briefly described, while those of Cathayornis? caudatus and
Largirostrornis are described in Chinese. Largirostrornis appears to have
a ginglymoideal articulation on metatarsal II however, which is similar to
Hulsanpes, Patagopteryx and Vorona, but unlike confuciusornithids. Also up
for consideration as a non-ornithurine member of the Yandangornis + Pygostylia
group (and thus comparable to Hulsanpes) is Jibeinia, which has a
proximally fused metatarsus that is similar to enantiornithines. So the
revised placement of Hulsanpes should be a non-ornithurine member of the
Yandangornis + Pygostylia clade, which includes the possibility of
enantiornithine or "jibeiniid" affinity.
Also, here are the pedal proportions of
Jibeinia (prepared for James Farlow) if anyone wants them.
The lengths given are percentage of metatarsal
III length, which is 16.3 mm, without the distal tarsals. Unguals are
measured in a straight line from most proximal to most distal point. There
is no fifth metatarsal preserved. These are all from the right
pes.
mtI 13 I-1 20 u-I 31 mtII 93 II-1 21 II-2 25 u-II 35 mtIII 100 III-1 24 III-2 25 III-3 24 u-III 28 mtIV 99 IV-1 16 IV-2 14 IV-3 12 IV-4 19 u-IV 23 Finally, Fredericus Ruhe alerted me to the fact
that the unnamed Mongolian enantiornithine I mentioned in "Details on Jibeinia"
as being described by Dong (1993) is actually Otogornis.
Mickey Mortimer
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