[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

New Papers of Play

Proceedings of the Royal Society chock full o' dinosaury goodness...

Franz, R., Hummel, J., Kienzle, E., Kölle, P., Gunga, H.-C., and Clauss, M.
2008. Allometry of visceral organs in living amniotes and its implications
for sauropod dinosaurs. Proceedings of the Royal Society B: Biological
Sciences 276:1731-1736. doi: 10.1098/rspb.2008.1735.

ABSTRACT: Allometric equations are often used to extrapolate traits in
animals for which only body mass estimates are known, such as dinosaurs. One
important decision can be whether these equations should be based on mammal,
bird or reptile data. To address whether this choice will have a relevant
influence on reconstructions, we compared allometric equations for birds and
mammals from the literature to those for reptiles derived from both
published and hitherto unpublished data. Organs studied included the heart,
kidneys, liver and gut, as well as gut contents. While the available data
indicate that gut content mass does not differ between the clades, the organ
masses for reptiles are generally lower than those for mammals and birds. In
particular, gut tissue mass is significantly lower in reptiles. When
applying the results in the reconstruction of a sauropod dinosaur, the
estimated volume of the coelomic cavity greatly exceeds the estimated volume
of the combined organ masses, irrespective of the allometric equation used.
Therefore, substantial deviation of sauropod organ allometry from that of
the extant vertebrates can be allowed conceptually. Extrapolations of
retention times from estimated gut contents mass and food intake do not
suggest digestive constraints on sauropod dinosaur body size.

Li, D., Norell, M.A., Gao, K.-Q., Smith, N.D., and Makovicky, P.J. 2009. A
longirostrine tyrannosauroid from the Early Cretaceous of China. Proceedings
of the Royal Society B: Biological Sciences. doi: 10.1098/rspb.2009.0249.

ABSTRACT: The fossil record of tyrannosauroid theropods is marked by a
substantial temporal and morphological gap between small-bodied, Barremian
taxa, and extremely large-bodied taxa from the latest Cretaceous. Here we
describe a new tyrannosauroid, Xiongguanlong baimoensis n. gen. et sp., from
the Aptian?Albian Xinminpu Group of western China that represents a
phylogenetic, morphological, and temporal link between these disjunct
portions of tyrannosauroid evolutionary history. Xiongguanlong is recovered
in our phylogenetic analysis as the sister taxon to Tyrannosauridae plus
Appalachiosaurus, and marks the appearance of several tyrannosaurid hallmark
features, including a sharp parietal sagittal crest, a boxy basicranium, a
quadratojugal with a flaring dorsal process and a flexed caudal edge,
premaxillary teeth bearing a median lingual ridge, and an expanded axial
neural spine surmounted by distinct processes at its corners. Xiongguanlong
is characterized by a narrow and elongate muzzle resembling that of
Alioramus. The slender, unornamented nasals of Xiongguanlong are
inconsistent with recent hypotheses of correlated progression in
tyrannosauroid feeding mechanics, and suggest more complex patterns of
character evolution in the integration of feeding adaptations in
tyrannosaurids. Body mass estimates for the full-grown holotype specimen of
Xiongguanlong fall between those of Late Cretaceous tyrannosaurids and
Barremian tyrannosauroids, suggesting that the trend of increasing body size
observed in North American Late Cretaceous Tyrannosauridae may extend
through the Cretaceous history of Tyrannosauroidea though further
phylogenetic work is required to corroborate this.

Makovicky, P.J., Li, D., Gao, K.-Q., Lewin, M., Erickson, G.M., and Norell,
M.A. 2009. A giant ornithomimosaur from the Early Cretaceous of China.
Proceedings of the Royal Society B: Biological Sciences. doi:

ABSTRACT: Ornithomimosaurs (ostrich-mimic dinosaurs) are a common element of
some Cretaceous dinosaur assemblages of Asia and North America. Here, we
describe a new species of ornithomimosaur, Beishanlong grandis, from an
associated, partial postcranial skeleton from the Aptian-Albian Xinminpu
Group of northern Gansu, China. Beishanlong is similar to another
Aptian-Albian ornithomimosaur, Harpymimus, with which it shares a
phylogenetic position as more derived than the Barremian Shenzhousaurus and
as sister to a Late Cretaceous clade composed of Garudimimus and the
Ornithomimidae. Beishanlong is one of the largest definitive
ornithomimosaurs yet described, though histological analysis shows that the
holotype individual was still growing at its death. Together with the
co-eval and sympatric therizinosaur Suzhousaurus and the oviraptorosaur
Gigantraptor, Beishanlong provides evidence for the parallel evolution of
gigantism in separate lineages of beaked and possibly herbivorous
coelurosaurs within a short time span in Central Asia.

Sues, H.-D., and Averianov, A. 2009. A new basal hadrosauroid dinosaur from
the Late Cretaceous of Uzbekistan and the early radiation of duck-billed
dinosaurs. Proceedings of the Royal Society B: Biological Sciences. doi:

ABSTRACT: Levnesovia transoxiana gen. et sp. nov., from the Late Cretaceous
(Middle?Late Turonian) of Uzbekistan, is the oldest well-documented taxon
referable to Hadrosauroidea sensu Godefroit et al. It differs from a
somewhat younger and closely related Bactrosaurus from Inner Mongolia
(China) by a tall sagittal crest on the parietals and the absence of
club-shaped dorsal neural spines in adult specimens. Levnesovia,
Bactrosaurus and possibly Gilmoreosaurus represent the earliest radiation of
Hadrosauroidea, which took place during the Cenomanian?Turonian and possibly
in North America. The second, Santonian-age radiation of Hadrosauroidea
included Aralosaurus, Hadrosauridae and lineages leading to Tanius
(Campanian) and Telmatosaurus (Maastrichtian). Hadrosauridae appears to be
monophyletic, but Hadrosaurinae and Lambeosaurinae originated in North
America and Asia, respectively.

...and also:

de Souza Bittencourt, J., and A.W.A. Kellner. 2009. The anatomy and
phylogenetic position of the Triassic dinosaur Staurikosaurus pricei
Colbert, 1970. Zootaxa 2079:1-56.

ABSTRACT: We redescribe the holotype of the saurischian dinosaur
Staurikosaurus pricei Colbert, 1970 from Late Triassic Santa Maria Formation
(southern Brazil), following additional preparation that revealed new
anatomical features. A revised diagnosis is proposed and the published
synapomorphies for Dinosauria and less inclusive clades (e.g. Saurischia)
are evaluated for this species. Some characters previously identified as
present in the holotype, including the intramandibular joint,
hyposphene-hypantrum articulations in dorsal vertebrae, and a cranial
trochanter and trochanteric shelf on the femur, cannot be confirmed due to
poor preservation or are absent in the available material. In addition,
postcranial characters support a close relationship between S. pricei and
Herrerasaurus ischigualastensis Reig, 1963 (Late Triassic, Argentina),
forming the clade Herrerasauridae. Several pelvic and vertebral characters
support the placement of S. pricei as a saurischian dinosaur. Within
Saurischia, characters observed in the holotype, including the anatomy of
the dentition and caudal vertebrae, support theropod affinities. However,
the absence of some characters observed in the clades Theropoda and
Sauropodomorpha suggests that S. pricei is not a member of Eusaurischia.
Most morphological characters discussed in previous phylogenetic studies
cannot be assessed for S. pricei because of the incompleteness of the
holotype and only known specimen. The phylogenetic position of S. pricei is
constrained by that of its sister taxon H. ischigualastensis, which is known
from much more complete material.

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

"It's no wonder that truth is stranger
than fiction. Fiction has to make
                          -- Mark Twain