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Maastrichtian Reptile Sandstone + Coelurosauravus morphology + Bunostegos skeleton + more papers

Ben Creisler

A  number of recent (and not so recent) papers, mainly non-dino:

A paper from a few months ago, posted online but not yet officially
published on the journal website for Spanish Journal of Palaeontology:

Alejandro Blanco, Manuel Méndez & Josep Marmi (2015)
The fossil record of the uppermost Maastrichtian Reptile Sandstone
(Tremp Formation, northeastern Iberian Peninsula).
Spanish Journal of Palaeontology 30(1): 117-130

Free pdf:

Numerous localities with vertebrate remains, including dinosaurs
(sauropods, ornithopods, theropods and ankylosaurs), crocodiles and
turtles, are known in the Arén and Tremp Formations (Maastrichtian,
northeastern Iberian Peninsula). This diverse fossil record is
improving our understanding of the history of the latest Mesozoic
faunas in Europe. A conspicuous 7 meter thick sandstone and/or
microconglomerate level (the so called Reptile Sandstone) occurs near
the top of the 'lower red unit' of the Tremp Formation, about 10
meters below the base of the 'Vallcebre limestone', which is Danian in
age. Bone remains and ichnites are known in the Reptile Sandstone, and
represent one of the youngest vertebrate record in the Maastrichtian
of the Tremp Formation. New findings carried out north Barcelona
province complement the fossil assemblage of the Reptile Sandstone
with turtle, crocodile, theropod and possible sauropod remains in
addition to hadrosaurs.


V. V. Bulanov & A. G. Sennikov (2015)
New data on the morphology of the Late Permian gliding reptile
Coelurosauravus elivensis Piveteau.
Paleontological Journal 49(4): 413-423
DOI: 10.1134/S0031030115040048

Free pdf:


Based on the material from the type locality (Eliva Mountain,
Madagascar), the cranial morphology of the Late Permian gliding
reptile Coelurosauravus elivensis Piveteau, 1926 (Weigeltisauridae) is
redescribed. The diagnosis of the genus Coelurosauravus is emended
based on comparisons with East European weigeltisaurids of the genus
Rautiania. It is shown that C. elivensis and all weigeltisaurids lack
the postfrontals and supratemporals and have a small preorbital
fenestra between the maxilla and nasal, partially reduced lacrimal,
and large nasolacrimal duct piercing the prefrontal. The poor
development of ornamental outgrowths on the parietal and in the
ventral part of the squamosal as well as the small size of studied
individuals of C. elivensis are caused by their juvenile age.


Morgan L. Turner, Linda A. Tsuji, Oumarou Ide & Christian A. Sidor (2015)
The vertebrate fauna of the upper Permian of Niger—IX. The
appendicular skeleton of Bunostegos akokanensis (Parareptilia:
Journal of Vertebrate Paleontology (advance online publication)

Pareiasaurs were a group of herbivorous reptiles that lived during the
middle to late Permian (˜265–252 Ma) in what is modern-day Europe,
Asia, South America, and Africa. Field work in the Moradi Formation of
northern Niger has produced multiple elements of the appendicular
skeleton of the pareiasaur Bunostegos akokanensis. The considerable
size disparity and morphological variation among the elements suggest
that they represent ontogenetic stages ranging from relatively
juvenile to adult. Here we present the first description of the
scapulocoracoid, humerus, radius, ulna, pelvis, and femur of
Bunostegos as well as some of the first ontogenetic data for
postcranial osteology in pareiasaurs. As with the skull, numerous
postcranial autapomorphies characterize Bunostegos, including
laterally originating acromion process of the scapula; radius and ulna
with continuous articular surface on humerus; paired crests on the
olecranon process; ulna longer than humerus; pinched posterior margin
of the acetabular rim; robust pelvic symphysis extending the length of
the puboischiatic plate; lack of a distinct postaxial flange of the
femur; and an elaborated femoral lateral condyle wrapping over the
medial condyle. We incorporated data from the appendicular skeleton of
Bunostegos into a revised phylogenetic analysis of pareiasaur
relationships. The results of this analysis corroborate previous
cranial analyses that place Bunostegos between Guadalupian taxa and
the Lopingian velosaur subclade. Interestingly, several aspects of its
postcranial anatomy suggest that Bunostegos possessed relatively
upright forelimb posture, which would be unique among pareiasaurs and
possibly Permian amniotes as a whole.


Hendrik Klein, Spencer G. Lucas & Sebastian Voigt (2015)
Revision of the ?Permian-Triassic Tetrapod Ichnogenus
Procolophonichnium Nopcsa 1923 with Description of the New
Ichnospecies P. lockleyi.
Ichnos 22(3-4): 155-176

Procolophonichnium is a globally distributed but rare tetrapod
ichnogenus ranging from the ?Late Permian/Early Triassic through the
Late Triassic. A Permian age of the holotype from the Karoo of South
Africa, as has been proclaimed by some workers, is doubtful.
Descriptions lack coordinates of the type locality but suggest instead
a position in Lower Triassic strata. Procolophonichnium material from
North and South Africa, central Europe, North and South America is
re-evaluated. Furthermore, the new ichnospecies Procolophonichnium
lockleyi from the Upper Triassic of the Germanic Basin is introduced,
based on material with well-preserved trackways that show distinct
morphological features, such as an extended “heel” behind digit V.
Five ichnospecies are considered as valid: P. nopcsai (type
ichnospecies), P. haarmuehlensis, P. nectouxi (new comb.) and P.
polonicum as Procolophonichnium tracks from ?Upper Permian, Lower and
Middle Triassic strata, and P. lockleyi ichnosp. nov. from the Upper
Triassic. Trackmakers of Procolophonichnium were most likely
therapsids based on the digit configuration and the phalangeal formula
derived from preserved pads. A prococolophonid affinity, as was
generally proclaimed, or the attribution to other groups such as
captorhinids, is less probable.


Post Mesozoic stuff:

I. G. Danilov , V. B. Sukhanov, E. M. Obraztsova & N. S. Vitek (2015)
The first reliable record of trionychid turtles in the Paleocene of Asia.
Paleontological Journal 49(4): 407-412
DOI: 10.1134/S0031030115040061

A new soft-shelled turtle species (Trionychidae), Gobiapalone
palaeocenica sp. nov. is described based on an incomplete articulated
juvenile skeleton from an unnamed Upper Paleocene locality in the
Bugin Tsav Basin of Mongolia. This is the first reliable trionychid
record in the Paleocene of Asia.



Claudia P. Tambussi, Federico J. Degrange & Daniel T. Ksepka (2015)
Endocranial anatomy of Antarctic Eocene stem penguins: implications
for sensory system evolution in Sphenisciformes (Aves).
Journal of Vertebrate Paleontology 35(5):
Free pdf:

Penguins have a more than 60 million year long evolutionary history.
Thus, stem lineage fossil taxa are key to understanding their
evolution. Here, we present data on three virtual endocasts from stem
penguin skulls collected from the Eocene La Meseta Formation of
Seymour Island (Antarctica), along with comparative data from extant
penguins and outgroups. These fossils appear to belong to three
distinct species, and represent both the oldest (34.2 Ma) and the most
basal penguin taxa that have yielded endocast data. Data collected
from the fossils provide new support for several important shifts in
neuroanatomy and cranial skeletal anatomy along the transition from
stem to crown penguins, including (1) caudal expansion of the
eminentia sagittalis, (2) an increase in the overlap of the
telencephalon onto the cerebellum, (3) reduction of the bulbus
olfactorius, and (4) loss of the interaural pathway. The large
semicircular canal diameters of the Antarctic fossils as well as the
more crownward stem penguin Paraptenodytes antarcticus together
suggest that canal size increased in basal penguins relative to
outgroup taxa but later decreased near the crown radiation. As in most
other wing-propelled diving birds, the endocasts lack evidence of
cerebellar folds and possess a relatively large floccular recess.
Several aspects of the endocast morphology, including the exposure of
the tectum opticum in dorsal view and the rostral displacement of the
eminentia sagittalis away from the border of the cerebellum, are seen
neither in crown penguins nor in Procellariiformes (the extant sister
clade to Sphenisciformes) and so appear to represent unique characters
of these stem taxa.


Carolina Acosta Hospitaleche (2015)
Ameghiniana (advance online publication)
doi: 10.5710/AMGH.27.08.2015.2890

A new incomplete penguin skeleton belonging to Palaeeudyptes
klekowskii Myrcha, Tatur and Del Valle, 1990, a giant sphenisciform
from the Priabonian Submeseta Formation on Marambio/Seymour Island,
Antarctic Peninsula is here studied. A paleobiological discussion
derived from the morphology of this skeleton is also provided. A
thorough description of muscular origin and insertions, body mass,
body length, and diving duration estimations support the hypothesis
that the new specimen represents a marine bird that had a body weight
of 40–44 kg and was 133.2–143.2 cm long, with limited swimming skills.


Daniel T. Ksepka, Sarah Werning, Michelle Sclafani and Zachary M. Boles (2015)
Bone histology in extant and fossil penguins (Aves: Sphenisciformes)
JOURNAL OF ANATOMY (advance online publication)
DOI: 10.1111/joa.12367

Substantial changes in bone histology accompany the secondary
adaptation to life in the water. This transition is well documented in
several lineages of mammals and non-avian reptiles, but has received
relatively little attention in birds. This study presents new
observations on the long bone microstructure of penguins, based on
histological sections from two extant taxa (Spheniscus and
Aptenodytes) and eight fossil specimens belonging to stem lineages
(†Palaeospheniscus and several indeterminate Eocene taxa). High bone
density in penguins results from compaction of the internal cortical
tissues, and thus penguin bones are best considered osteosclerotic
rather than pachyostotic. Although the oldest specimens sampled in
this study represent stages of penguin evolution that occurred at
least 25 million years after the loss of flight, major differences in
humeral structure were observed between these Eocene stem taxa and
extant taxa. This indicates that the modification of flipper bone
microstructure continued long after the initial loss of flight in
penguins. It is proposed that two key transitions occurred during the
shift from the typical hollow avian humerus to the dense
osteosclerotic humerus in penguins. First, a reduction of the
medullary cavity occurred due to a decrease in the amount of
perimedullary osteoclastic activity. Second, a more solid cortex was
achieved by compaction. In extant penguins and †Palaeospheniscus, most
of the inner cortex is formed by rapid osteogenesis, resulting an
initial latticework of woven-fibered bone. Subsequently, open spaces
are filled by slower, centripetal deposition of parallel-fibered bone.
Eocene stem penguins formed the initial latticework, but the
subsequent round of compaction was less complete, and thus open spaces
remained in the adult bone. In contrast to the humerus, hindlimb bones
from Eocene stem penguins had smaller medullary cavities and thus
higher compactness values compared with extant taxa. Although cortical
lines of arrested growth have been observed in extant penguins, none
was observed in any of the current sampled specimens. Therefore, it is
likely that even these ‘giant’ penguin taxa completed their growth
cycle without a major pause in bone deposition, implying that they did
not undergo a prolonged fasting interval before reaching adult size.


This story was in the media a few months ago--drugged out dinosaurs.
Here's the paper in open access:

One hundred million year old ergot: psychotropic compounds in the Cretaceous?
Palaeodiversity 8: 13–19

A fungal sclerotium similar to those of the genus Claviceps, commonly
known as ergot, was discovered infecting a grass floret in Early–mid
Cretaceous Myanmar amber. The fungus, described as Palaeoclaviceps
parasiticus gen. n., sp. n. is characterized by an erect black
sclerotium with flattened hyphal outgrowths and adjacent conidia
consistent in morphology with those of extant species of Claviceps.
The lobed hyphal outgrowths on the distal end of the sclerotium
separate the fossil from all extant species of Claviceps as well as
other sclerotium- producing fungi in the Clavicipitaceae. The fossil
shows that the original hosts of the Clavicipitaceae could have been
grasses and establishes the presence of the Clavicipitaceae and
Poaceae in the Early–mid Cretaceous.