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RE: Gobipipus, new enantiornithine from Mongolia and other new Mesozoic bird papers



Wow, this paper has been in the ether a long time.  As stated on my website-

"Chatterjee and 
  Kurochkin (1994) and Kurochkin (1995, 1996) separated ZPAL MgR-I/33 and two 
  new specimens in the PIN collections from ZPAL MgR-I/34 as a new taxon of 
palaeognath. 
  This was to be described in Nature by Chatterjee, Kurochkin and Mikhailov as 
  "Gobipipus reshetovi" (Mourer-Chauvire, 1995). Indeed, such a reference 
  is cited as a manuscript by Kurochkin (1996) and Starck and Ricklefs (1998) 
  and "in press" in Nature by Kurochkin (1995)."

http://archosaur.us/theropoddatabase/Ornithothoraces.htm#Gobipipusreshetovi

Mickey Mortimer

----------------------------------------
> Date: Wed, 18 Dec 2013 15:45:35 -0800
> From: bcreisler@gmail.com
> To: dinosaur@usc.edu
> Subject: Gobipipus, new enantiornithine from Mongolia and other new Mesozoic 
> bird papers
>
> From: Ben Creisler
> bcreisler@gmail.com
>
> A number of new Mesozoic bird papers:
>
> E. N. Kurochkin, S. Chatterjee & K. E. Mikhailov (2013)
> An embryonic enantiornithine bird and associated eggs from the
> Cretaceous of Mongolia.
> Paleontological Journal 47(11): 1252-1269
> DOI: 10.1134/S0031030113110087
> http://link.springer.com/article/10.1134/S0031030113110087
>
>
>
> Enantiornithes is the most speciose clade of Cretaceous birds, but
> many taxa are known from isolated postcranial skeletons. Two embryonic
> enantiornithine bird skeletons of Gobipipus reshetovi gen. et sp. nov.
> from the Upper Cretaceous (Campanian) Barun Goyot Formation of the
> Gobi Desert in Mongolia provide new insights into the anatomy,
> radiation, and mode of development of early avialans. In recent times,
> both enantiornithine and ornithuromorph birds are known from the Barun
> Goyot Formation as well as from the Djadokhta and Nemegt Formations.
> The 80-million-year-old Gobipipus skeletons encased within eggshells
> shows several features characteristic of enantiornithine birds. The
> wing skeleton and shoulder girdle show morphological features
> indicating that Gobipipus ac
> Gobipipus reshetovi gen. et sp. nov. is quite distinct from the
> sympatric enantiornithine species Gobipteryx minuta from the same
> strata in many anatomical features. Phylogenetic analysis of 26
> avialan ingroup taxa based on distribution of 202 characters indicate
> that Gobipipus is a basal member of enantiornithine birds along with
> Confuciusornis and shares more characters with ornithuromorphs than
> previously recognized. The embryonic nature of Gobipipus specimens
> sheds new light on the developmental history of enantiornithine birds.
> The well-ossified bones of the fore- and hind limbs, and fusion of
> many skeletal elements indicate a precocial mode of development in
> Gobipipus. Apparently Gobipipus hatchlings could walk away from the
> ground nests as soon as they emerged from their eggs. The asymmetry of
> egg poles are unique features of Gobipipus eggs (oogenus Gobioolithus)
> among Cretaceous avialans. The microstructure of the shell in
> Gobioolithus eggs with the embryos of Gobipipus is typical avian (of
> ornithoid basic type) and less ratite-like in morphology of the spongy
> layer than is that in the other possible egg-remains of enantiornitine
> birds (oofamily Laevisoolithidae).
> ==
>
> J. K. O’Connor & N. V. Zelenkov (2013)
> The phylogenetic position of Ambiortus: Comparison with other Mesozoic
> birds from Asia.
> Paleontological Journal 47(11): 1270-1281
> DOI: 10.1134/S0031030113110063
> http://link.springer.com/article/10.1134/S0031030113110063
>
> Since the last description of the ornithurine bird Ambiortus
> dementjevi from Mongolia, a wealth of Early Cretaceous birds have been
> discovered in China. Here we provide a detailed comparison of the
> anatomy of Ambiortus relative to other known Early Cretaceous
> ornithuromorphs from the Chinese Jehol Group and Xiagou Formation. We
> include new information on Ambiortus from a previously undescribed
> slab preserving part of the sternum. Ambiortus is superficially
> similar to Gansus yumenensis from the Aptian Xiagou Formation bu
> shares more morphological features with Yixianornis grabaui
> (Ornithuromorpha: Songlingornithidae) from the Jiufotang Formation of
> the Jehol Group. In general, the mosaic pattern of character
> distribution among early ornithuromorph taxa does not reveal obvious
> relationships between taxa. Ambiortus was placed in a large
> phylogenetic analysis of Mesozoic birds, which confirms morphological
> observations and places Ambiortus in a polytomy with Yixianornis and
> Gansus.
>
> ==
>
> Walter J. Bock (2013)
> The furcula and the evolution of avian flight.
> Paleontological Journal 47(11): 1236-1244
> DOI: 10.1134/S0031030113110038
> http://link.springer.com/article/10.1134/S0031030113110038
>
> The presence of a short furcula in Archaeopteryx suggests that this
> bird possessed a small, shortfibered, cranial portion of the pinnate
> m. pectoralis originating from the furcula and possibly from the
> aponeurosis between the furcula and the coracoid and cartilaginous
> sternum, and inserting on the cranial edge of the humerus, and an
> equally small, short-fibered pinnate caudal part of the same muscle
> arising from the presumably cartilaginous sternum and inserting on the
> ventral surface of the deltoid crest of the humerus. In Archaeopteryx,
> the cranial-most portion of the m. pectoralis protracted the wing and
> held it in place against the backward pressure, or drag, of the air
> when the bird flew. There is no basis for postulating that the caudal
> part of the m. pectoralis in Archaeopteryx was sufficiently large for
> active flapping flight, although this presumably small muscle probably
> held the wings in a horizontal position necessary for aerial
> locomotion. The muscle fibers of all parts of the m. pectoralis were
> short because the small distance between its origin and insertion. The
> combination of features in the pectoral system of Archaeopteryx
> indicates strongly that this bird was a specialized glider, not an
> active flapping flier. Avian flight started from the trees downward,
> not from
>
> ==