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



Mickey, thank you for confirming this!

I was sure that was a name I had encountered before.

On Wed, December 18, 2013 8:53 pm, Mickey Mortimer wrote:
> 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
>>
>> ==
>


Thomas R. Holtz, Jr.
Email: tholtz@umd.edu   Phone: 301-405-4084
Office: Centreville 1216
Senior Lecturer, Vertebrate Paleontology
Dept. of Geology, University of Maryland
http://www.geol.umd.edu/~tholtz/
Fax: 301-314-9661

Faculty Director, Science & Global Change Program, College Park Scholars
http://www.geol.umd.edu/sgc
Fax: 301-314-9843

Mailing Address:        Thomas R. Holtz, Jr.
                        Department of Geology
                        Building 237, Room 1117
                        University of Maryland
                        College Park, MD 20742 USA