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Lotsa New Papers

Hi All -

   The latest bunch of stuff, the most "exciting" first:

Zhang, Z., Hou, L., Hasegawa, Y., O'Connor, J., Martin, L.D., and Chiappe, L.M. 2006. The first Mesozoic heterodactyl bird from China. Acta Geologica Sinica (English Edition) 80(5):631-635.

Don't get all drooly over this one -- the evidence for heterodactyly is pretty poor, IMHO. The thing, _Dalingheornis liweii_, does have a rather longish tail, though, reminiscent of _Liaoxiornis_ (which is supposedly also matches in size).

Novas, F.E., Ezcurra, M.D., and Agnolin, F.L. 2006. Humerus of a basal abelisauroid theropod from the Late Cretaceous of Patagonia. Revista del Museo Argentino de Ciencias Naturales, n.s. 8(1):63-68.

Agnolin, F.L., Novas, F.E., and Lio, G. 2006. Neornithine bird coracoid from the Upper Cretaceous of Patagonia. Ameghiniana 43(1):245-248.

Coria, R., Currie, P.J., and Carabajal, A.P. 2006. A new abelisauroid theropod from northwestern Patagonia. Canadian Journal of Earth Sciences 43(9): 1283-1289.

ABSTRACT: The Argentinean record of abelisauroid theropods begins in the Early Cretaceous (Ligabueino) and spans most of the Late Cretaceous, from Cenomanian (Ilokelesia, Xenotarsosaurus, and Ekrixinatosaurus) to Campanian-Maastrichtian (Abelisaurus, Carnotaurus, Aucasaurus, and Noasaurus). A fragmentary specimen of a theropod dinosaur was collected in 2000 from the middle section of the Lisandro Formation (Turonian?) at Cerro Bayo Mesa, Neuquén Province, Argentina. The fossil-bearing level, which is part of the Lisandro Formation that also yielded the remains of the basal ornithopod Anabisetia saldiviai, corresponds to a reddish, massive mudstone linked with fluvial channel deposits. The theropod identified as MCF-PVPH-237 is an abelisauroid theropod that increases our knowledge about the evolution of South American Abelisauroidea and is the first record of this clade from the Lisandro Formation.

I don't have this one yet, and so don't know what, if anything, is the name of this new beast.

Candeiro, C.R.A., and Martinelli, A.G. 2006. A review of paleogeographical and chronostratigraphical distribution of mesoeucrocodylian species from the upper Cretaceous beds from the Bauru (Brazil) and Neuquén (Argentina) groups, southern South America. Journal of South American Earth Sciences 22(1-2):116-129. doi: 10.1016/j.jsames.2006.08.001.

ABSTRACT: This article offers a detailed overview of mesoeucrocodylian assemblages recovered from the Late Cretaceous southern South America Bauru and Neuquén groups as a result of extensive research during the past 110 years. The Bauru (Brazil) and Neuquén (Argentina) groups yield numerous mesoeucrocodylian remains, mainly of Turonian-late Maastrichtian (Late Cretaceous) age. The majority of the discoveries were made in the Adamantina and Marília formations of Minas Gerais and São Paulo states, Brazil, and Candeleros and Bajo de la Carpa formations of Neuquén and Río Negro provinces, Argentina. Sixty formally described species of mesoeucrocodylians are recognized on the basis of disarticulated materials; among them, notosuchians, sebecosuchians, and peirosaurids are the best represented. At least one species is common to the Bauru and Neuquén groups, and close phylogenetic affinities are postulated for the remaining taxa. The fossil record of these two South American units shows three main peaks of diversity: in the Cenomanian of Argentina, the Santonian of Argentina and Brazil, and the Maastrichtian of Brazil. The absence of notosuchians and sebecosuchians in the late Campanian-Maastrichtian of Patagonia is coincident with the paleoenvironmental changes in that landmass by that time, as well as with the increase in diversity of several groups of theropod dinosaurs. In contrast, highly specialized carnivorous mesoeucrocodylians are abundant in the Maastrichtian of the Bauru group of Brazil, whereas other tetrapod carnivorous groups are scarcely represented.

Jiang, B., and Sha, J. 2006. Late Mesozoic stratigraphy in western Liaoning, China: a review. Journal of Asian Earth Sciences 28(4-6):205-217. doi: 10.1016/j.jseaes.2005.07.006.

ABSTRACT: Based on progress in stratigraphic and paleontological studies, we discuss the subdivision of Late Mesozoic strata in western Liaoning, focusing on the controversies surrounding the relationship of the Jiufotang and Shahai formations, and whether or not the Zhanglaogongtun and Banlashan formations exist as distinct lithologic units. We describe the Late Mesozoic strata at representative sections associated with the new discoveries. We also discuss the correlation of Late Mesozoic strata between western Liaoning and eastern Heilongjiang and their implications for the ages of the strata in Liaoning.

Among other things, one important tidbit in here: the Shahai and Jiufotang formations look like lateral equivalents, not successive units.

Paik, I.S., Huh, M., Park, K.H., Hwang, K.G., Kim, K.S., and Kim, H.J. 2006. Yeosu dinosaur track sites of Korea: the youngest dinosaur track records in Asia. Journal of Asian Earth Sciences 28(4-6):457-468. doi: 10.1016/j.jseaes.2005.11.007.

ABSTRACT: Eighty two dinosaur trackways were newly discovered in Upper Cretaceous lacustrine deposits on islands in the vicinity of Yeosu, Korea. Most dinosaur tracks occur in marginal lake deposits with polygonal desiccation cracks. The dinosaur tracks at the Yeosu site include 65 ornithopod trackways, 16 theropod trackways and one sauropod trackway. The prevalence of ornithopod tracks and the limited occurrence of sauropod tracks at the Yeosu site evidently reflect decreased sauropod diversity in the Upper Cretaceous. All ornithopod trackways represent bipeds, and most of the ornithopod tracks are similar to Caririchnium from other sites of the Korean peninsula. All fossil wood specimens collected in the study area represent conifers (three species of cupressaceous and two species of taxodiaceous conifers, and a new species) except for one, which is a discotyledon. It is thus inferred that the southwestern part of the Korean Peninsula was primarily covered with mesic forests with taxodiaceous trees during the Late Cretaceous. The K-Ar age of the Yeosu tracksite is determined as 81-65 Ma (Camapnian to Maastrichtian). It indicates that the Yeosu track site contains the last records of dinosaurs living in Asia. Consequently, semi-arid palaeoclimatic conditions, together with a large lake as a persistent water source and rich vegetation of gymnosperm trees as food, resulted in the preservation of abundant dinosaur tracks in the Upper Cretaceous on the Korean Peninsula.

Jouve, S., Iarochene, M., Bouya, B., and Amaghzaz, M. 2006. New material of Argochampsa krebsi (Crocodylia: Gavialoidea) from the Lower Paleocene of the Oulad Abdoun Basin (Morocco): phylogenetic implications. Geobios 39(6):817-832. doi: 10.1016/j.geobios.2005.07.003.

ABSTRACT: New material from the Lower Paleocene of the Oulad Abdoun Basin, Morocco, including postcranial material permits a new description of Argochampsa krebsi. The odontoid process of the axis bears a strong lateral apophysis, continuous on the anterolateral margin of the centrum. This process has never been observed such developed in other crocodylians. The single preserved posterior cervical vertebra exhibits a particularly short neural spine, much shorter than that is observed in Alligator mississippiensis, Crocodylus porosus, and Gavialis gangeticus. A phylogenetic analysis, including new coding of A. krebsi, provide a result that is globally congruent with previous works, but differs significantly in the relationships of the gavialoids. A. krebsi is more closely related to G. gangeticus than is Eogavialis africanum. The South American Ikanogavialis gameroi and Gryposuchus colombianus form a polytomy, and are more closely related to G. gangeticus than is Piscogavialis jugaliperforatus, a gavialoid from Peru. The South American gavialoids may thus not be monophyletic. This result may indicate, contrary to previous result, a more complex paleobiogeographic history. Thus, a multiple invasion of South America by gavialoids from Africa is equally parsimonious with a single invasion, and an invasion from South American to Asia is equally parsimonious with an invasion from Africa.

Jerry D. Harris
Director of Paleontology
Dixie State College
Science Building
225 South 700 East
St. George, UT  84770   USA
Phone: (435) 652-7758
Fax: (435) 656-4022
E-mail: jharris@dixie.edu
and     dinogami@gmail.com

"Trying to estimate the divergence times
of fungal, algal or prokaryotic groups on
the basis of a partial reptilian fossil and
protein sequences from mice and humans
is like trying to decipher Demotic Egyptian with
the help of an odometer and the Oxford
English Dictionary."
              -- D. Graur & W. Martin (_Trends
                  in Genetics_ 20[2], 2004)