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New Papers Assassin



A few more snuck in since I posted earlier...



Vullo, R., Buscalioni, A.D., Marugán-Lobón, J., and Moratalla, J.J. 2009. First 
pterosaur remains from the Early Cretaceous Geological Magazine 146(6):931-936. 
doi: 10.1017/S0016756809990525.

ABSTRACT: Pterosaur teeth from the Early Cretaceous Lagerstätte of Las Hoyas 
(Spain) are described. We reassess the track from this site previously ascribed 
to a pterosaur, concluding that it is a theropod footprint. The teeth belong to 
two pterodactyloid taxa: a basal Istiodactylidae similar to Haopterus and an 
indeterminate Ornithocheiridae. From a palaeoecological point of view, the 
occurrence of such pterosaurs in the freshwater wetland palaeobiota of Las 
Hoyas strengthens the evidence of the similarity of this Spanish locality to 
the famous Early Cretaceous Lagerstätten of Liaoning in China.





Hinić-Frlog, S., and Motani, R. 2009. Relationship between osteology and 
aquatic locomotion in birds: determining modes of locomotion in extinct 
Ornithurae. Journal of Evolutionary Biology. doi: 
10.1111/j.1420-9101.2009.01909.x.

ABSTRACT: The evolutionary history of aquatic invasion in birds would be 
incomplete without incorporation of extinct species. We show that aquatic 
affinities in fossil birds can be inferred by multivariate analysis of skeletal 
features and locomotion of 245 species of extant birds. Regularized 
discriminant analyses revealed that measurements of appendicular skeletons 
successfully separated diving birds from surface swimmers and flyers, while 
also discriminating among different underwater modes of swimming. The high 
accuracy of this method allows detection of skeletal characteristics that are 
indicative of aquatic locomotion and inference of such locomotion in bird 
species with insufficient behavioural information. Statistical predictions 
based on the analyses confirm qualitative assessments for both foot-propelled 
(Hesperornithiformes) and wing-propelled (Copepteryx) underwater locomotion in 
fossil birds. This is the first quantitative inference of underwater modes of 
swimming in fossil birds, enabling future studies of locomotion in extinct 
birds and evolutionary transitions among locomotor modes in avian lineage.






Lyson, T.R., and Joyce, W.G. 2009. A revision of Plesiobaena     (Testudines: 
Baenidae) and an assessment of baenid ecology across the K/T boundary. Journal 
of Paleontology 83(6):833-853. doi: 10.1666/09-035.1.

ABSTRACT: Over the course of the last two decades, the baenid taxon Plesiobaena 
has typically been thought to consist of two named species, Plesiobaena antiqua 
(Campanian) and Plesiobaena putorius (Paleocene), along with an unnamed species 
from the Maastrichtian, but the interrelationship of these three taxa was never 
explored in an explicit phylogenetic context. Herein we present or re-describe 
a number of relevant specimens and provide a cladistic analysis of Baenidae 
using species only as terminal taxa. The phylogenetic analysis clearly reveals 
that Plesiobaena in the traditional sense is a paraphyletic assemblage relative 
to the clade formed by Gamerabaena sonsalla and Palatobaena spp., thus 
demanding some nomenclatural adjustments. In particular, Plesiobaena putorius 
is moved to a new genus, Cedrobaena, and the unnamed taxon from the 
Maastrichtian is formally named Peckemys brinkman. Many of the new Cedrobaena 
putorius and Peckemys brinkman specimens described herein were found at the 
Turtle Graveyard locality in Slope County, North Dakota, along with four other 
turtle taxa, increasing the turtle diversity of this locality to at least six 
taxa. Although this indicates that Turtle Graveyard is the world's most diverse 
fossil turtle thanatocoenosis, a comparable diversity is found in modern river 
systems in the southeastern United States today. Our phylogenetic analysis 
indicates that seven out of nine latest Cretaceous baenid turtle lineages 
survived into the Paleocene, four of which are interpreted as being durophagous.




~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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
http://cactus.dixie.edu/jharris/


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