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A New Papers Getaway

Tanoue, K., You, H.-L., and Dodson, P. 2009. Comparative anatomy of selected
basal ceratopsian dentitions. Canadian Journal of Earth Sciences
46(6):425-439. doi: 10.1139/E09-030.

ABSTRACT: The dental structure of basal ceratopsians is described.
Evolutionary trends in maxillary and dentary teeth of basal ceratopsians
include decrease and possible loss of enamel on the occluding side of tooth
crowns, increase in the angle of wear facet, development of a prominent
primary ridge and deep indentations on mesial and distal sides of the
primary ridge, and increase in tooth size in neoceratopsians. Premaxillary
teeth in the basalmost ceratopsian Yinlong and basal neoceratopsian
Archaeoceratops oshimai exhibit wear facets and denticles along the carina,
which imply use for feeding. Maxillary and dentary teeth of basal
ceratopsians were probably not as effective in feeding as those in
ceratopsids because of the relatively less prominent primary ridges. Some
dental characters can be used to identify taxon and tooth position of
isolated basal ceratopsian teeth.

Kim, J.Y., Lockley, M.G., Kim, H.M., Lim, J.-D., and Kim, K.S. 2009. The
oldest dinosaur tracks from Korea, Ornithopodichnus jinjuensis ichnogen. et
ichnosp. nov. (Jinju Formation, Lower Cretaceous): implications for
polarities in ornithopod foot morphology. Cretaceous Research. doi:

ABSTRACT: Twelve trackways of ornithopods from Lower Cretaceous lacustrine
margin deposits of Jinju Formation represent the oldest dinosaur trackways
described from Korea. The site, discovered during highway construction, was
rescued by removing the most important trackways to the Korean Natural
Heritage Center in Daejeon, where they are on permanent display. The new
ichnotaxon Ornithopodichnus jinjuensis ichnogen. et ichnosp. nov. is
recognized as a distinctive robust tridactyl track, slightly wider than long
(l/w ratio = 0.91), with positive (inward) rotation. The toe prints are very
thick, broad and U-shaped, resulting in a trefoil outline with a smoothly
rounded hind margin. Digit III is short and projects anteriorly much less
than digit II and IV ( = weak mesaxony). Divarication of digits II-IV is
about 70° with interdigital angle II-III larger than III-IV. Trackway width
is narrow and the stride length/track length ratio is about 4.2-4.6. The
Ornithopodichnus trackways evidently represent gregarious blunt-toed
Iguanodon-like bipedal ornithopods, although poorly preserved manus traces
are discerned in a few trackways. Ornithopodichnus is distinct from other
well known iguanodontid tracks that display much stronger mesaxony and
indicates a polarity in ornithopod foot morphology that can be verified by
reference to known foot skeletons.

Ezcurra, M.D. 2009. Theropod remains from the uppermost Cretaceous of
Colombia and their implications on for the palaeozoogeography of western
Gondwana. Cretaceous Research. doi: 10.1016/j.cretres.2009.08.004.

ABSTRACT: Dinosaur remains from Upper Cretaceous outcrops of northern
Gondwana are extremely rare, in contrast with the much richer sample of
coeval beds from southern Gondwana. Dinosaur remains from the uppermost
Cretaceous Ortega locality of the Upper Magdalena Basin (Maastrichtian) of
the Department of Tolima, Colombia, provides new information on northern
Gondwanan faunas of this time. A revision of dinosaur material from this
outcrop, consisting of three theropod shed teeth, reveals the presence of
two morphotypes. One of them is referred to Abelisauridae based on the
presence of crowns with mesial margin with a strong curvature beginning at
about the second-third of the crown height and straight to slightly concave
distal margin. The second morphotype exhibits un-serrated mesial and distal
margins without carinae and no constriction at the base of the crown, a
combination of features only observed in unenlagiine dromaeosaurids within
Theropoda. Members of these clades are also present in coeval beds of
southern and central South America, Madagascar, northern Africa, and India,
indicating a cosmopolitan distribution in western and central Gondwana
during the Late Cretaceous. Regarding South America, abelisaurid and
probably dromaeosaurid theropods are recorded across a large latitudinal
area, from the Equator to considerably high palaeo-latitudes in Patagonia,
and probably spanning quite different environmental conditions.

Witzmann, F., Scholz, H., and Ruta, M. 2009. Morphospace occupation of
temnospondyl growth series: a geometric morphometric approach. Alcheringa
33(3):237-255. doi: 10.1080/03115510903043606.

ABSTRACT: A morphometric analysis based on 16 landmarks (specific geometric
points) identified on the skull roof of different growth stages of various
temnospondyls revealed patterns of shape change during ontogeny. Data from
50 individuals from 12 taxa, encompassing euskelians (dissorophoids,
eryopids and zatracheids) and stereospondylomorphs were plotted in a
morphospace diagram defined by two principal-component axes (PC 1 and PC 2)
of a principal-component analysis of the shape variables. The morphospace
occupation reflects phylogenetic relationships of the main clades of
temnospondyls. All stereospondylomorphs investigated here have similar
ontogenetic trajectories with long intervals on PC 1. Eryopids and
zatracheids have shortened their trajectories on PC 1 and are separated in
morphospace relative to the stereospondylomorphs and dissorophoids. Outgroup
comparison with Cochleosaurus bohemicus (Friccaron, 1876) suggests that a
long ontogenetic trajectory with gradual development represents the
plesiomorphic condition for temnospondyls. More derived stereospondylomorphs
(among the taxa considered here, but excluding groups such as derived
rhytidosteids and brachyopoids) increased the length of their trajectories
on PC 1 and show a peramorphic pattern, resulting in the long and slender
skull of piscivorous predators. Dissorophoids exhibit truncated ontogenetic
trajectories and occupy the morphospace region of larval
stereospondylomorphs, thus attaining a paedomorphic appearance probably by
hypomorphosis. Amphibamid and branchiosaurid dissorophoids have clearly
distinguishable larval and postlarval developments, indicating that these
forms had evolved a lissamphibian-like type of metamorphosis.

Leardi, J.M., and Pol, D. 2009. The first crocodyliform from the Chubut
Group (Chubut Province, Argentina) and its phylogenetic position within
basal Mesoeucrocodylia. Cretaceous Research. doi:

ABSTRACT: A new crocodyliform specimen is presented here found in the Cerro
Castaño Member of the Cerro Barcino Formation (Chubut Group). The material
consists of cranial and postcranial remains that represent a new taxon that
has strong affinities with Peirosauridae, but also shares derived features
present in Araripesuchus. The phylogenetic relationships of this new taxon
were tested through a cladistic analysis depicting it as a member of the
Peirosauridae. The inclusion of Barcinosuchus within this clade of basal
mesoeucrocodylians is supported by the presence of hypapophyses up to the
third or fourth dorsal vertebrae, anterolateral facing edge on postorbital,
quadrate dorsal surface divided in two planes by a ridge; mandibular
symphysis tapering anterirorly in ventral view, lateral surface of dentary
convex anterior to mandibular fenestra, distal body of quadrate well
developed, anteroposteriorly thin and lateromedially broad. The new specimen
broadens the temporal and geographical distribution of Peirosauridae during
the Cretaceous of Gondwana, representing the southern-most and the most
ancient record of the group in Patagonia. The new material also provides
insights on the postcranial anatomy of peirosaurids, a group that has been
so far studied almost exclusively from cranial material.

Candeiro, C.R.A., and Rich, T. 2009. Overview of the Late Cretaceous biota
of the western São Paulo state, Brazil, Bauru Group. Journal of South
American Earth Sciences. doi: 10.1016/j.jsames.2009.08.001.

ABSTRACT: The Turonian-Maastrichtian beds of the Bauru Group, western São
Paulo State (Brazil), have yielded a diverse biota. The nine species of
mesoecrocodilians are all mesosuchians. There is a single frog, a
Neubatrachia. The vertebrates include, four types of fishes, a neobatrachian
frog, an anilioid snake, two lizard, six species of podocnemid turtles, nine
species of mesosuchian mesoecrocodilians three theropods, two birds, five
titanosaurid sauropods, and one mammalian. The invertebrates include one
cyclo, one cyclophoroid and eight pulmonates. Plants are represented by only
two carophyte species. The biota from western São Paulo State is one the
most diverse of the Late Cretaceous in Brazil. The biota from this area
confirms that Bauru Group was connected to Patagonia and other Gondwanan
areas during the Late Cretaceous.

Michel, E., Nikolaeva, S., Dale-Skey, N., and Tracey, S. 2009. Contributions
to the discussion on electronic publication. Bulletin of Zoological
Nomenclature 66(1):4-19.

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

"Experience is what you get when
you didn't get what you wanted."

                                 -- unknown