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Things Are New Papers All Over



Cau, A., and Arduini, P. 2008. Enantiophoenix electrophyla gen. et sp. nov.
(Aves, Enantiornithes) from the Upper Cretaceous (Cenomanian) of Lebanon and
its phylogenetic relationships. Atti della Società Italiana di Scienze
Naturali e del Museo Civico di Storia Naturale di Milano 149(2):293-324.

ABSTRACT: The phylogenetic affinities of a new enantiornithine bird,
Enantiophoenix electrophyla gen. et sp. nov. from the Cenomanian of Lebanon,
are reviewed. It differs from other known Mesozoic birds on the basis of two
scapular autapomorphies. The inclusion of Enantiophoenix in a phylogenetic
analysis of Mesozoic birds indicates that it is a basal member of a clade of
enantiornithines, Avisauridae, whose known distribution includes North
America, Europe and Gondwana.




Wang, X., Campos, D.d.A., Zhou, Z., and Kellner, A.W.A. 2008. A primitive
istiodactylid pterosaur (Pterodactyloidea) from the Jiufotang Formation
(Early Cretaceous), northeast China. Zootaxa 1813:1-18.

ABSTRACT: A new pterosaur, Hongshanopterus lacustris gen. et sp. nov., from
the Early Cretaceous Jiufotang Formation, western Liaoning, China is
described. The specimen (IVPP V14582) consists of a skull preserved in
palatal view and some isolated cervical vertebrae. Based on the
labiolingually compressed teeth with a triangular crown Hongshanopterus
lacustris is referred to the Istiodactylidae. It presents several
plesiomorphic features such as the teeth not confined to the anterior third
of the skull but extended more posteriorly, and is thus considered the most
primitive member of this group. This new species also differs from other
istiodactylids by having more teeth, some showing the crown distinctively
directed posteriorly. Three other members of the Istiodactylidae are
currently represented in the Jiufotang deposits: Nurhachius ignaciobritoi,
Istiodactylus sinensis and Longchengpterus zhaoi. To those we add
Liaoxipterus brachyognathus, previously classified in the Ctenochasmatidae
but that also has triangular labiolingually compressed teeth, and is a
potential senior synonym of Lonchengpterus zhaoi. The palatal anatomy of
Hongshanopterus lacustris also agrees with previous hypothesis that
considers Istiodactylidae more closely related to the Anhangueridae than to
Pteranodon (or Pteranodontidae).




Hasiotis, S.T. 2008. Reply to the Comments by Bromley et al. of the paper
?Reconnaissance of the Upper Jurassic Morrison Formation ichnofossils, Rocky
Mountain Region, USA: paleoenvironmental, stratigraphic, and paleoclimatic
significance of terrestrial and freshwater ichnocoenoses? by Stephen T.
Hasiotis. Sedimentary Geology 208(1-2):61-68. doi:
10.1016/j.sedgeo.2008.04.004.

     (...a reply to:  Bromley, R.G., Buatois, L.A., Genise, J.F.,
Labandeira, C.C., Mángano, M.G., Melchor, R.N., Schlirf, M., and Uchman, A.
2007. Comments on the paper ?Reconnaissance of Upper Jurassic Morrison
Formation ichnofossils, Rocky Mountain Region, USA: Paleoenvironmental,
stratigraphic, and paleoclimatic significance of terrestrial and freshwater
ichnocoenoses? by Stephen T. Hasiotis. Sedimentary Geology 200(1-2):141-150.
doi: 10.1016/j.sedgeo.2006.11.007.)




Barrett, P.M., Butler, R.J., Novas, F.E., Moore-Fay, S.C., Moody, J.M.,
Clark, J.M., and Sánchez-Villagra, M.R. 2008. Dinosaur remains from the La
Quinta Formation (Lower or Middle Jurassic) of the Venezuelan Andes.
Paläontologische Zeitschrift 82(2):163-177.




Higham, T.E., and Biewener, A.A. 2008. Integration within and between
muscles during terrestrial locomotion: effects of incline and speed. Journal
of Experimental Biology 211(14):2303-2316. doi: 10.1242/jeb.016139.

ABSTRACT: Animals must continually adapt to varying locomotor demands when
moving in their natural habitat. Despite the dynamic nature of locomotion,
little is known about how multiple muscles, and different parts of a muscle,
are functionally integrated as demand changes. In order to determine the
extent to which synergist muscles are functionally heterogeneous, and
whether this heterogeneity is altered with changes in demand, we examined
the in vivo function of the lateral (LG) and medial (MG) gastrocnemius
muscles of helmeted guinea fowl (Numida meleagris) during locomotion on
different inclines (level and uphill at 14°) and at different speeds (0.5
and 2.0 m s?1). We also quantified function in the proximal (pMG) and distal
(dMG) regions of the MG to examine the extent to which a single muscle is
heterogeneous. We used electromyography, sonomicrometry and tendon force
buckles to quantify activation, length change and force patterns of both
muscles, respectively. We show that the LG and MG exhibited an increase in
force and stress with a change in gait and an increase in locomotor speed,
but not with changes in incline. While the LG and MG exhibited similar
levels of stress when walking at 0.5 m s?1, stress in the LG was 1.8 times
greater than in the MG when running at 2.0 m s?1. Fascicle shortening
increased with an increase in speed on both inclines for the LG, but only on
the level for the pMG. Positive work performed by the LG exceeded that of
the pMG and dMG for all conditions, and this difference was magnified when
locomotor speed increased. Within the MG, the pMG shortened more, and at a
faster rate than the dMG, resulting in a greater amount of positive work
performed by the pMG. Mean spike amplitude of the electromyogram (EMG)
bursts increased for all muscle locations with an increase in speed, but
changes with incline were more variable. The functional differences between
the LG and MG are likely due to the different moments each exerts at the
knee, as well as differences in motor unit recruitment. The differences
within the MG are likely due to motor unit recruitment differences, but also
differences in architecture. Fascicles within the dMG insert into an
extensive aponeurosis, which results in a higher apparent dynamic stiffness
relative to fascicles operating within the pMG. On the level surface, the
greater compliance of the pMG leads to increased stretch of its fascicles at
the onset of force, further enhancing force production. Our results
demonstrate the capacity for functional diversity between and within muscle
synergists, which occur with changes in gait, speed and grade.



Butler, R.J., and Galton, P.M. 2008. The 'dermal armour' of the ornithopod
dinosaur Hypsilophodon from the Wealden (Early Cretaceous: Barremian) of the
Isle of Wight: a reappraisal. Cretaceous Research. doi:
10.1016/j.cretres.2008.02.002.

ABSTRACT: The small ornithopod dinosaur Hypsilophodon foxii, from the Early
Cretaceous (Barremian) of the Isle of Wight, England, is one of the best
known of all dinosaurs; however, the reported presence of dermal armour in
this taxon is poorly understood. We reassess the evidence for dermal armour:
in all specimens in which they can be identified the plate-like structures
formerly identified as armour are associated with the lateral surfaces of
the distal sections of the anterior dorsal ribs. Comparison with the
ornithopods Talenkauen and Thescelosaurus suggests that these structures do
not represent armour, but are instead mineralised cartilaginous intercostal
plates. Such plates were probably widespread in basal ornithopods, but have
not been recognised to date due to incomplete preservation or variation in
the timing and degree of mineralisation.




Butler, R.J., and Zhao, Q. 2008. The small-bodied ornithischian dinosaurs
Micropachycephalosaurus hongtuyanensis and Wannanosaurus yansiensis from the
Late Cretaceous of China. Cretaceous Research. doi:
10.1016/j.cretres.2008.03.002.

ABSTRACT: The type material of the small-bodied ornithischian dinosaurs
Micropachycephalosaurus hongtuyanensis and Wannanosaurus yansiensis from the
Late Cretaceous of China is reviewed. Micropachycephalosaurus, from the
Wangshi Formation (Campanian) of Shandong Province, was originally referred
to the clade Pachycephalosauria, but some later authors have considered it a
nomen dubium. However, despite the extremely fragmentary nature of the
holotype specimen, Micropachycephalosaurus can be diagnosed by the presence
of prominent grooves on the ventral surface of the centra of the posterior
dorsal vertebra. Unambiguous pachycephalosaur synapomorphies cannot be
identified in the currently available material, and we consider this taxon
Cerapoda incertae sedis. Wannanosaurus, from the Xiaoyan Formation
(Campanian-?early Maastrichtian) of Anhui Province, can be diagnosed by the
extreme flexure of the humerus, and is clearly referable to
Pachycephalosauria on the basis of a large number of synapomorphies.
Assessment of the phylogenetic placement of this Wannanosaurus within
Pachycephalosauria is complicated by the probable juvenile nature of the
holotype and paratype specimens.



González-Riga, B.J., Previtera, E., and Pirrone, C.A. 2008. Malarguesaurus
florenciae gen. et sp. nov., a new titanosauriform (Dinosauria, Sauropoda)
from the Upper Cretaceous of Mendoza, Argentina. Cretaceous Research. doi:
10.1016/j.cretres.2008.06.006.


ABSTRACT: Malarguesaurus florenciae gen. et sp. nov. is a new and robust
somphospondylian titanosauriform (Dinosauria, Sauropoda) from the Neuquén
basin, Mendoza Province, Argentina. The specimen comes from Upper Cretaceous
strata assigned to the Portezuelo Formation (upper Turonian-lower
Coniacian). It includes proximal, middle and distal caudal vertebrae,
chevrons, dorsal ribs, and appendicular bones. Malarguesaurus is
characterized by the following association of characters: (1) proximal
caudal neural spines vertically directed, with a concave caudal border, and
a caudodorsal corner forming a right angle; (2) procoelous-opisthoplatyan
proximal and middle caudal vertebrae associated with procoelous distal
caudal centra; and (3) distal caudal neural spines having a concave and
depressed dorsal border. A preliminar cladistic analysis placed
(Ligabuesaurus +(Malarguesaurus + Phuwiangosaurus)) as a sister taxon of
Titanosauria. Unique among the titanosauriforms, Malarguesaurus has
procoelous distal caudal centra associated with procoelous-opisthoplatyan
proximal caudals. This discovery is a new evidence of the morphologic
diversity of the South American sauropods.




Longrich, N. 2008. An ornithurine-dominated avifauna from the Judith River
Group (Campanian, Upper Cretaceous) of Alberta, Canada. Cretaceous Research.
doi: 10.1016/j.cretres.2008.06.007.

ABSTRACT: Relatively little is known the diversity of Late Cretaceous
ornithurines, and it has generally been assumed that the ornithurine sister
taxon, the Enantiornithes, were the dominant birds in Late Cretaceous
continental ecosystems. Here, an ornithurinedominated avifauna is described
from the terrestrial Judith River Group (Campanian, Upper Cretaceous) of
southern Alberta. On the basis of the most common element, the coracoid,
eight species can be identified; all represent ornithurines. More precise
identifications are hindered by the fragmentary nature of the material, but
some of the forms described here resemble Cretaceous birds known from
elsewhere in North America and Asia. The Judithian birds show considerable
size disparity; a coracoid from the Irvine mammal locality belongs to a
sparrow-sized bird, making it one of the smallest known Cretaceous birds,
while the peacock-sized Palintropus is among the largest birds known from
the Cretaceous. Surprisingly, no enantiornithine fossils were identified.
These fossils show that the Ornithurae had diversified considerably by the
end of the Campanian, and that they were the dominant birds in some North
American ecosystems. The diversification of the Ornithurae towards the end
of the Cretaceous could help explain how this clade managed to survive the
end Cretaceous mass extinction.




Kim, S.B., Kim, Y.G., Jo, H.R., Jeong, K.S., and Chough, S.K. 2008.
Depositional facies, architecture and environments of the Sihwa Formation
(Lower Cretaceous), mid-west Korea with special reference to dinosaur eggs.
Cretaceous Research. doi: 10.1016/j.cretres.2008.05.016.

ABSTRACT: This paper presents detailed facies and architectural analyses and
palaeoenvironmental reconstruction of the Sihwa Formation (Lower
Cretaceous), midwest Korea, which comprises an about 3-km-thick non-marine
succession containing abundant dinosaur eggshells. Based on constituent
facies, bedset geometry, stacking pattern, and bounding surface
characteristics, the entire succession can be classified into three
architectural elements. Element I occurs along the basin margin and shows a
monotonous stacking of tabular or crudely stratified conglomeratic units. It
represents alluvial-fan deposits of debris-flow-dominated fan and
sheetflood-dominated fan. Element II is characterized by multi-storey, sheet
or upward-widening, conglomeratic channel-fills whose maximum thickness
exceeds 1.5 m. Each channel-fill unit is encased within red?brown silty
sandstones of Element III with sharp erosional bases but diffuse gradational
upper boundaries. It consists generally of (1) cut-and-fill deposit (trough
cross-stratified or openwork conglomerate) in the lower part and (2)
composite low-relief bar deposit (lenticular conglomerate and stratified
gravelly sandstone) in the upper part. Shallowness of each cut-and-fill
unit, absence of fining-upward lateral accretion package and the
predominance of simple-bar deposit collectively suggest deposition from
ephemeral braided streams. Element III typically shows a finingupward
stacking of (1) single- or multi-storey small-scale (<1.5 m thick) channel
fills with limited lateral extent of less than 15 m, (2) poorly sorted,
graded and diffusely bounded silty conglomerates or gravelly siltstones with
discontinuous gravel sheets and pockets and (3) homogeneous or graded,
red?brown fine-grained deposits with calcretes and burrows in ascending
order. Element III is interpreted as channel-margin to floodplain, including
crevasse channel fill, crevasse splay and floodplain fines.
     The entire sequence of the Sihwa Formation can be divided into the
alluvial-fan and terminal-fan successions. The alluvial-fan succession
displays a progradational stacking pattern and indicates a low rate of basin
subsidence at the initial phase of rifting. The upper terminal-fan
succession consists of proximal braided stream and distal floodplain
deposits in the western and central part of the basin and is characterized
by the axial dispersal pattern and an aggradational stacking. It suggests
rapid subsidence of the basin floor during the main phase of rifting. The
asymmetrical cross-basin distribution of each architectural element reflects
a half-graben structure of the basin with steep-gradient fault-bounded
eastern margin (footwall block) and gently sloped, flexural western margin
(hangingwall block). The predominance of ephemeral braided-stream deposits
along with red?brown fine-grained floodplain deposits with common calcretes
indicates arid to semi-arid palaeoclimates.
     Approximately 140 dinosaur eggs (Faveoloolithidae and Dendroolithidae)
were identified mainly from the (gravelly) siltstones and small-scale
channel fills of Element III deposits and partly from the cut-and-fill
conglomerates of Element II deposits. The eggs commonly retain their
original oval shape but are invariably breached and stuffed with the
substrate of gravels and silt. They are either isolated or clustered,
forming a circular concentration in plan view. The abundant yield of eggs,
more than 20 eggs in 5 separate nests from a single depositional unit,
suggests a dense population of the parental dinosaurs. The repetitive
occurrence in many stratigraphic horizons reflects site preference as a
nesting habitat of the near-channel or abandoned channel areas.




Vullo, R., and Néraudeau, D. 2008. Cenomanian vertebrate assemblages from
southwestern France: a new insight into the European mid-Cretaceous
continental fauna. Cretaceous Research. doi: 10.1016/j.cretres.2008.05.010.

ABSTRACT: Cenomanian paralic deposits of Charentes (southwestern France)
have yielded abundant vertebrate microremains, including rather diversified
continental taxa (e.g., frogs, turtles, crocodilians, dinosaurs, pterosaurs,
lizards, and mammals). In this preliminary report, the succession of faunal
assemblages observed is briefly described in relation to palaeoenvironmental
change resulting from the Cenomanian-early Turonian transgressive episode.
Continental forms occur commonly in estuarine and shallow marine rocks of
the lower part of the Cenomanian stage, but seem to be lacking in younger
strata deposited in more open marine settings. Among an unexpected
biodiversity, several non-marine groups (e.g., ziphodont crocodilians,
carcharodontosaurid and troodontid dinosaurs, marsupial-like mammals) are
recorded for the first time in the lower Upper Cretaceous of Europe, thus
providing new palaeobiogeographical indications for this poorly documented
part of the world.




     Many more new goodies in the advance area for _Cretaceous Research_
that I haven't gotten to yet...!


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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/

"Football is like chess, only without
the dice."
   --- German soccer player Lukas
         Podolski