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Lakeview New Papers

Lots O' New Stuff (TM), in part 'cuz of the new ish of JVP, but others, too...!

Ye, Y. 2008. A review on the study of Mamenchisaurus; pp. 1-7 in Wang, Y. and 
Deng, T. (eds.), Proceedings of the Eleventh Annual Meeting of the Chinese 
Society of Vertebrate Paleontology. China Ocean Press, Beijing. 

Wang, Q., Bin, L., Kan, Z., Li, K., Zhu, B., and Ji, X. 2008. 
Paleoenvironmental Reconstruction of Mesozoic Dinosaurs Fauna in Sichuan Basin. 
Geological Publishing House, Beijing, 189 pp.

Knoll, F. 2008. On the Procompsognathus postcranium (Late Triassic, Germany). 
Geobios. doi: 10.1016/j.geobios.2008.02.002. 

ABSTRACT: A review of the historical background of the material housed in the 
Staatliches Museum fÃr Naturkunde (Stuttgart) and ascribed to Procompsognathus 
triassicus (Upper Triassic, Germany) is provided. The systematic position of 
the postcranial remains is discussed. The combined results of cladistic 
analyses suggest that the type material, an incomplete postcranial skeleton in 
two pieces (SMNS 12591), is from a theropod close to Segisaurus and 
Coelophysis. An isolated manus (SMNS 12352a) is definitely not theropodan, but 
could be from any small basal archosaur. The remarkable diversity of the 
carnivorous guild that dwelled in southern Germany before the end-Triassic 
events is underlined.

Keller, G., Abramovich, S., Berner, Z., and Adatte, T. 2008. Biotic effects of 
the Chicxulub impact, K-T catastrophe and sea level change in Texas. 
Palaeogeography, Palaeoclimatology, Palaeoecology. doi: 

ABSTRACT: Biotic effects of the Chicxulub impact, the K-T event and sea level 
change upon planktic foraminifera were evaluated in a new core and outcrops 
along the Brazos River, Texas, about 1500 km from the Chicxulub impact crater 
on Yucatan, Mexico. Sediment deposition occurred in a middle neritic 
environment that shallowed to inner neritic depths near the end of the 
Maastrichtian. The sea level fall scoured submarine channels, which were 
infilled by a sandstone complex with reworked Chicxulub impact spherules and 
clasts with spherules near the base. The original Chicxulub impact ejecta layer 
was discovered 45-60 cm below the sandstone complex, and predates the K-T mass 
extinction by about 300,000 years.
     Results show that the Chicxulub impact caused no species extinctions or 
any other significant biotic effects. The subsequent sea level fall to inner 
neritic depth resulted in the disappearance of all larger (>150 Îm) deeper 
dwelling species creating a pseudo-mass extinction and a survivor assemblage of 
small surface dwellers and low oxygen tolerant taxa. The K-T boundary and mass 
extinction was identified 40-80 cm above the sandstone complex where all but 
some heterohelicids, hedbergellids and the disaster opportunistic guembelitrids 
went extinct, coincident with the evolution of first Danian species and the 
global Î13C shift. These data reveal that sea level changes profoundly 
influenced marine assemblages in near shore environments, that the Chicxulub 
impact and K-T mass extinction are two separate and unrelated events, and that 
the biotic effects of this impact have been vastly overestimated.

Falkingham, P.L., Margetts, L., Smith, I.M., and Manning, P.L. 2008. 
Reinterpretation of palmate and semi-palmate (webbed) fossil tracks: insights 
from finite element modelling. Palaeogeography, Palaeoclimatology, 
Palaeoecology. doi: 10.1016/j.palaeo.2008.09.011.

ABSTRACT: A track from the Late Cretaceous previously described as being 
generated by a semi-palmate bird was studied with the aid of high resolution 
laser scanning. Substrate conditions at the time of track formation were 
diagnosed (fine grained, soft, waterlogged sediment) and used to constrain a 
Finite Element track simulator. The indentation of a non-webbed virtual 
tridactyl foot in such conditions created a resultant track with features 
analogous to âwebbingâ between digits. This âwebbingâ was a function of 
sediment deformation and subsequent failure in 3D, specific to rheology. 
Variation of substrate conditions and interdigital angle were incrementally 
stepped. Apparent webbing impressions were clearly developed only within a 
limited range of sediment conditions and pedal geometry.
     The implications of this work are that descriptions of âwebbedâ tracks 
should account for the possibility that webbing was indirectly formed through 
sediment failure and not necessarily the direct impression of a webbed foot. 
Additionally, dating the earliest occurrence of webbed feet in the fossil 
record, and potentially extending phylogenetic ranges, should be treated with 
caution when based upon evidence from tracks.

Sidor, C.A., Damiani, R., and Hammer, W.R. 2008. A new Triassic temnospondyl 
from Antarctica and a review of Fremouw Formation biostratigraphy. Journal of 
Vertebrate Paleontology 28(3):656-663. doi: 

ABSTRACT: A new temnospondyl, Kryostega collinsoni, gen. et sp. nov., is 
described on the basis of a large snout fragment from the Triassic upper 
Fremouw Formation of Antarctica. K. collinsoni is characterized by greatly 
enlarged teeth of the transvomerine and parachoanal tooth rows, a reduced 
transvomerine tooth row, as well as a distinct process on the palatal surface 
of the premaxilla. Although key palatal and tabular features are not preserved, 
the shape and position of the external naris, choana, and anterior palatal 
vacuity suggest that K. collinsoni may be allied to the Heylerosauridae or 
basal Mastodonsauridae. The discovery of K. collinsoni in the upper Fremouw is 
surprising, given that Triassic vertebrates from Antarctica are typically 
considered a subset of coeval taxa from the Karoo Basin of South Africa. Based 
on its unique occurrence in Antarctica, K. collinsoni suggests that high 
latitude Triassic tetrapods had a more restricted geographic distribution than 
 considered. Biostratigraphically, the fauna of the upper Fremouw Formation is 
best correlated with the Cynognathus Assemblage Zone of South Africa's Beaufort 
Group, although the lack of speciesâlevel identifications for many of the 
Antarctic fossils precludes a more refined correlation. A review of the 
Triassic fossil record identifies several tetrapods that make their first 
appearance in the Fremouw, with a later appearance in the Karoo Basin, 
suggesting that the high latitude regions of Gondwana might have served as an 
important area for speciation.

Parker, W.G., Stocker, M.R., and Irmis, R.B. 2008. A new desmatosuchine 
aetosaur (Archosauria: Suchia) from the Upper Triassic Tecovas Formation 
(Dockum Group) of Texas. Journal of Vertebrate Paleontology 28(3):692-701. doi: 

ABSTRACT: A small aetosaur skeleton collected in 1939 from the Tecovas 
Formation of Texas and assigned to Desmatosuchus is reassigned to a new taxon, 
Sierritasuchus macalpini. Phylogenetic analysis suggests that Sierritasuchus is 
a member of the Desmatosuchinae. It can be distinguished from other 
desmatosuchines by two autapomorphies: (1) recurved spines on the lateral 
plates that are triangular in cross-section with a sharply ridged anterior 
edge; and (2) the presence of a sharp, ventrally oriented ridge on the 
posterior faces of the dorsal eminences of the paramedian plates, as well as a 
unique combination of characters including the presence of an anterior bar on 
the paramedian and lateral plates, a random pattern of ornamentation on the 
paramedian plates, and a dorsal eminence that contacts the posterior plate 
margin of the paramedian plates. Histological study of the holotypic plates in 
combination with comparison to a growth series in Typothorax, and 
size-independent growth
 indicators such as neurocentral suture closure suggests that the specimen is 
neither a young juvenile nor a fully-grown adult. The recognition of 
morphologically distinct specimens such as the holotype and referred material 
of Sierritasuchus demonstrates that past practices of assigning aetosaur 
specimens to known taxa based on superficial resemblance has masked diversity 
in this clade. Voucher specimens for biochronologic and biogeographic analyses 
should be carefully investigated before being used for such studies.

Butler, R.J., Porro, L.B., and Norman, D.B. 2008. A juvenile skull of the 
primitive ornithischian dinosaur Heterodontosaurus tucki from the 'Stormberg' 
of southern Africa. Journal of Vertebrate Paleontology 28(3):702-711. doi: 

ABSTRACT: Heterodontosaurids are an enigmatic group of primitive ornithischian 
dinosaurs best known from the Early Jurassic of southern Africa. Because fossil 
material is rare and often poorly preserved, the taxonomy, systematics, and 
palaeobiology of this clade are controversial. Here we describe a new partial 
skull of a juvenile Heterodontosaurus tucki from the 'Stormberg' of South 
Africa. This skull provides new information on the cranial anatomy of this 
taxon as well as insights into cranial ontogeny, sexual dimorphism and tooth 
replacement in heterodontosaurids. Few ontogenetic changes in dental morphology 
occur in Heterodontosaurus, supporting previous suggestions that tooth 
characters are informative for species-level taxonomy in heterodontosaurids. 
Furthermore, the presence of well-developed caniniform teeth in the juvenile 
specimen does not support the hypothesis that these represent secondary sexual 
characteristics in heterodontosaurids. Computed tomography reveals that
 replacement teeth are absent in both juvenile and adult specimens of 
Heterodontosaurus; however, the difference in the absolute size of the teeth 
between the juvenile and adult specimens demonstrates that replacement must 
have occurred during ontogeny.

Canudo, J.I., Royo-Torres, R., and Cuenca-BescÃs, G. 2008. A new sauropod: 
Tastavinsaurus sanzi gen. et sp. nov. from the Early Cretaceous (Aptian) of 
Spain. Journal of Vertebrate Paleontology 28(3):712-731. doi: 

ABSTRACT: The new sauropod dinosaur Tastavinsaurus sanzi, gen. et sp. nov., 
from the early Aptian of Spain is described. The holotype is a partially 
articulated skeleton of an adult individual recovered from the Arsis-1 site in 
PeÃarroya de Tastavins (Teruel) at the base of the marine Xert Formation. It 
is one of the most complete and best-preserved sauropod dinosaur skeletons from 
the European Early Cretaceous. The fossil remains comprise the three caudalmost 
thoracic vertebrae, part of a fourth, nine thoracic rib fragments, sacrum, 25 
caudal vertebrae, 21 chevrons, both ilia, pubes, ischia and femora, right 
tibia, right fibula, six metatarsals, and seven pedal phalanges (including four 
unguals). The new taxon is defined by 19 autapomorphies. In our cladistic 
analysis, Tastavinsaurus is the sister-taxon of the North American Venenosaurus 
within Titanosauriformes, which includes the Brachiosauridae, Somphospondyli, 
and Titanosauria. The new taxon provides new information about the
 diversity of non-brachiosaurid titanosauriforms during the Early Cretaceous in 
Europe and paleobiogeographic relationships between Europe and North America.

Benson, R.B.J. 2008. New information on Stokesosaurus, a tyrannosauroid 
(Dinosauria: Theropoda) from North America and the United Kingdom. Journal of 
Vertebrate Paleontology 28(3):732-750. doi: 

ABSTRACT: A partial postcranial skeleton from the Late Jurassic (Tithonian) of 
Dorset, England represents a new species of the theropod dinosaur 
Stokesosaurus, Stokesosaurus langhami. S. langhami is a member of 
Tyrannosauroidea, showing a distinct median vertical ridge on the lateral 
surface of the ilium, a prominent shelf medial to the preacetabular notch, a 
pronounced ischial tubercle, and a tibia that is elongate relative to the 
femur. One of only two definitive Jurassic tyrannosauroids known from more than 
isolated elements, it is the largest Jurassic tyrannosauroid reported to date 
and provides additional evidence for the presence of relatively small- or 
medium-sized basal tyrannosauroids in Asia, North America, and Europe during 
the Late Jurassic. The occurrence of Stokesosaurus in the Tithonian of the UK 
and USA and the absence of tyrannosauroids in contemporaneous west African 
faunas supports the hypothesis of a paleobiogeographic link during the Late 
Jurassic between North
 America and Europe, to the exclusion of Africa.

Mayr, G., Hazevoet, C.J., Dantas, P., and CachÃo, M. 2008. A sternum of a very 
large bony-toothed bird (Pelagornithidae) from the Miocene of Portugal. Journal 
of Vertebrate Paleontology 28(3):762-769. doi: 

ABSTRACT: The sternum of a very large bony-toothed bird (Pelagornithidae) from 
the Miocene of Portugal is described. The three-dimensionally preserved 
specimen is one of the largest sterna of a volant bird known to date, and more 
complete than the only other pelagornithid sternum reported so far. It is 
tentatively assigned to Pelagornis miocaenus Lartet, 1857, which is the only 
bony-toothed bird known from the Miocene of Europe. The specimen shows several 
unique features, including the presence of a marked cranial projection of the 
carina sterni, which probably abutted the extremitas sternalis of the furcula, 
and a large, steep-walled opening in the cranial portion of the facies 
visceralis. The corpus sterni further has a highly unusual shape in that it is 
very deep, with a strongly vaulted facies visceralis. It is likely that these 
characteristics are due to anatomical constraints imposed by the very large 
size of pelagornithids, which may have reached a wingspan of up to 6 m and
 probably were incapable of sustained flapping flight.

Williamson, T.E., and Weil, A. 2008. Metatherian, mammals from the Naashoibito 
Member, Kirtland Formation, San Juan Basin, New Mexico and their biochronologic 
and paleobiogeographic significance. Journal of Vertebrate Paleontology 
28(3):803-815. doi: 10.1671/0272-4634(2008)28[803:MMFTNM]2.0.CO;2.

ABSTRACT: Isolated teeth representing several taxa of metatherian mammals were 
recovered from NMMNH locality L-4005 in the Naashoibito Member, Kirtland 
Formation, San Juan Basin, northwestern New Mexico. These include fragments of 
upper and lower molars and a fragmentary premolar that are referred to 
indeterminate âpediomyids,â an isolated p2 or p3 that is referred to an 
indeterminate peradectid, and two lower molars, an m1 or m2 and an m4 that are 
referable to the hatcheriforme metatherian Glasbius cf. G. intricatus. Two 
upper molar fragments are also tentatively referred to Glasbius. These taxa are 
part of the Alamo Wash local fauna. Glasbius has been proposed as a potential 
first appearance datum for the Lancian North American Land Mammal âageâ 
(NALMA). The presence of both Glasbius and the multituberculate Essonodon 
within the Naashoibito Member support an age correlative with other formations 
producing Lancian faunas. A Lancian age for the Naashoibito Member suggests
 that there is a significant disconformity between the top of the late 
Campanian De-na-zin Member, which is constrained by radiometric dates to be 
about 73 Ma, and the base of the Naashoibito Member. Terrestrial faunas of 
Lancian age show differences that have been attributed to provinciality. The 
widespread distribution of mammalian index taxa indicates some degree of faunal 
homogeneity during this interval, but the refined stratigraphic correlation of 
the Alamo Wash local fauna allows us to recognize other taxa as geographically 
restricted, as opposed to asynchronous.

Modesto, S.P., and Botha-Brink, J. 2008. Evidence of a second, large 
archosauriform reptile in the Lower Triassic Katberg Formation of South Africa. 
Journal of Vertebrate Paleontology 28(3):914-917. doi: 

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

"I have made this letter longer
than usual because I lack the
time to make it shorter."
                      -- Blaise Pascal