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Dinosaur News



From: Ben Creisler bh480@scn.org

Here are some recent refs and short communications about 
dinosaurs I don't recall seeing mentioned here:

Nath T.T., Yadagiri, P. & Moitra, A.K., 2002. First record 
of armoured dinosaur from the Lower Jurassic Kota 
Formation, Pranhita-Godavari Valley, Andhra Pradesh. 
JOURNAL OF THE GEOLOGICAL SOCIETY OF INDIA. 59 (6) : 575-
577 (June 2002).
For the first time, skeletal remains of an armoured 
dinosaur (Ornithischia: Ankylosauria) were found in the 
red clay bed of the Kota Formation, Pranhita-Godavari 
Valley, Andhra Pradesh. The bed occurs 2 m below the 
marker limestone unit of the Kota Formation. The 
collection includes parts of skull, 30 specimens of body 
armour, vertebrae and parts of girdle bones. The 
characteristics of armour plates, skull and teeth indicate 
that these fossils belong to ankylosauria. The ankylosaurs 
are less known from the Lower Jurassic period. The 
detailed studies of the present material are likely to 
throw light on the evolutionary history of these dinosaurs.

Anais da Academia Brasileira de Ciências 74 (2) (June 
2002): Short Communications:

FRANCO-ROSAS, ALDIRENE C. 2002. METHODOLOGICAL PARAMETERS 
FOR THE IDENTIFICATION AND TAXONOMIC CLASSIFICATION OF 
ISOLATED THEROPODOMORPH TEETH.  Anais da Academia 
Brasileira de Ciências 74 (2): 367.
Isolated teeth of small theropods are relatively common in 
Brazilian Cretaceous deposits, where several well-
preserved specimens have been found. Here we describe and 
present morphological and morphometric parameters that can 
be used for the taxonomic identification of such material. 
This study is based on thirty teeth from four sites 
situated in the São Paulo and Minas Gerais states. This 
material comes from the Adamantina and Marilia formations 
of the Bauru Basin and was examined under stereomicroscope 
and scanning electron microscope.
The following characteristics were considered effective 
for the characterization of different morphological 
classes, some of which were already mentioned in the 
literature: 1 - number of denticles per millimeter (DPM), 
which is measured in the central region of the posterior 
margin; 2 - tooth base diameter (BW); 3 - preserved 
portion of the tooth total height (AT); 4 - shape of the 
basal transverse section (FABL); 5 - shape of the 
denticles. Based on the features above three morphologic 
groups were identified, tentatively referred to the 
Maniraptoriformes (Dromaeosauridae, Velociraptorinae and 
Troodontidae) as follows:
Morphotype 1 - long, rounded denticles showing a non-
uniform distal portion and different slopes, with slightly 
pronounced interdenticle spaces. This morphology is 
similar to the teeth described for Velociraptorinae and 
Troodontidae.
Morphotype 2 - long, sharp denticles in the distal 
portion, with deep rifts among them. This morphology is 
very similar to the one shown by North American specimens, 
associated with Dromaeosauridae.
Morphotype 3 - short, round denticles, with bow-shaped 
distal portion and deep interdenticle spaces, not recorded 
before. They might represent a new group, endemic for 
Brazil. - ( December 20, 2001 ).


RIFF, DOUGLAS RIFF, ALEXANDER W.A. KELLNER, BRYN MADER & 
DALE RUSSELL 2002. ON THE OCCURRENCE OF AN AVIAN VERTEBRA 
IN CRETACEOUS 
STRATA OF MOROCCO, AFRICA. Anais da Academia Brasileira de 
Ciências 74 (2): 367-368.

So far, osteological remains of Mesozoic birds in Gondwana 
are very limited, with some occurrences in South America 
(around 10 non-neornithine records), Australia (one), 
Antarctica (one), and Africa. In the latter, this record 
is restricted to incomplete limb elements and a partial 
skeleton from Madagascar, and footprints from Late 
Cretaceous strata of Morocco. Here we report an isolated 
dorsal vertebra found in the Albo-Cenomanian sandstones of 
the Kem Kem region, Southeastern Morocco. The specimen is 
housed in the Canadian Museum of Nature (NMC 50852) and 
represents the first avian osteological record from 
Mesozoic strata of the Continental Africa. 
The vertebra is well preserved but incomplete. The length 
of the centrum is 21.0 mm with a preserved height of 25.6 
mm. In some areas the bone surface was broken off 
revealing the pneumatized internal structure (apparently 
less developed compared to most recent avian taxa). The 
centrum in elongated, amphicoelous, cylindrical and 
slightly constricted medially, with the ventral margins 
arched upwards; no pleurocoels or foramina are present on 
the lateral surface. The articular facets have a 
subcircular outline. 
The main avian characteristic of NMC 50852 is the large 
neural canal, with the ratio between the height of the 
neural canal and the height of the cranial surface of the 
centrum of 0.67 (in extant birds, this ratio varies from 
0.5 to 2.75 and in theropods it is lesser than 0.4). The 
neural arch is not very tall, being elongated and showing 
a cranial and caudal groove. The transverse processes and 
zygapophyses are not preserved. On the left side, a small 
prominence possibly represents the base of the 
parapophysis. 
The characteristics of this vertebra differ from the main 
avian clades (Alvarezsauridae, Confunciornithidae, 
Enantiornithes, Hesperornithiformes, Icthyornithiformes, 
Neornithes). The main similarities of the Moroccan 
specimen are observed in the dorsal vertebrae of Rahona 
ostromi, a basal bird from the Late Cretaceous of 
Madagascar. Notwithstanding, some differences such as the 
neural canal, which is larger in the Moroccan specimen, 
and the presence of pleurocoels in Rahona ostromi suggest 
that NMC 50852 belongs to a different taxon of basal 
birds. - ( December 20, 2001 ).

Trotta, Marcelo N.F. 2002. MORPHOLOGICAL VARIATION AMONG 
THE APPENDICULAR BONES OF THE TITANOSAURIDAE (DINOSAURIA: 
SAUROPODA) FROM THE BAURU BASIN (UPPER CRETACEOUS) OF 
PEIRÓPOLIS (MG), BRAZIL.  Anais da Academia Brasileira de 
Ciências 74 (2): 366.
Several appendicular bones from the collection of the 
Departamento Nacional de Produção Mineral (DNPM/RJ) are 
being described for the first time. The bones were 
collected by L. I. Price between 1949 and 1974, and were 
unearthed from three main quarries: "Site 1 or Caieira'' 
(which also includes vertebral series and two 
sacra); "Serra da Galga'' and "Rodovia'' (Campos DA and 
Kellner AWA, 1999, Nat Sci Mus Mongr 15:143-166). None of 
these sites has yielded a single individual. The bones 
vary in size; most bear distinct morphological features, 
which allow their classification into different 
morphotypes. The scapulae display two morphotypes, based 
on the presence or absence of a medial prominence on the 
inner face. The biggest scapulae show further variation in 
the upper distal margin of the blade, which bears doubled 
expansions. The coracoids do not vary, but one displays an 
unique protuberance on its anterior upper corner. Based on 
overall shape and frontal profile, the sternal plates are 
either triangular or "T'' shaped. The ulnae display two 
different morphotypes, based on the presence or absence of 
an excavation on their distal articular areas. This 
excavation gives the distal surface of this element a 
reniform outline. The radii have been grouped into four 
morphotypes based on the overall robustness, shape of the 
distal articular facets, development of the proximal 
medial projection, and the presence of ridges running 
along the shaft. The pubes display three morphotypes based 
on the presence of a longitudinal ridge on the pubic apron 
and features of the iliac pedicle. The ischia display 
three morphotypes based on the presence or absence of a 
reentrance below the pubic pedicle and shape of the distal 
shaft. The femora may be either robust or slender. The 
fibulae display two morphotypes based on the presence or 
absence of an anterior trochanter and a medial oblique 
ridge. - ( December 20, 2001 ).

SANDRA R. TORRES, LEONARDO S. AVILLA, ÉRIKA A.L. ABRANTES 
& LÍLIAN P. BERGQVIST 2002. DINOSAUR OSTEODERMS FROM THE 
ADAMANTINA FORMATION, UPPER CRETACEOUS OF SÃO PAULO STATE, 
BRAZIL. Anais da Academia Brasileira de Ciências 74 (2): 
366.
In the austral spring of 2001, the Laboratório de 
Macrofósseis/IGEO/UFRJ conducted an expedition to some 
Cretaceous fossil localities in the state of São Paulo. 
The expedition produced several fossils, including 
icnofossils, molluscs, fishes, turtles, crocodilomorphs, 
and dinosaurs. We describe herein two dinosaur osteoderms 
from the Fazenda Furnas (Adamantina Formation, Upper 
Cretaceous, Bauru Basin), Municipality of Jales, São Paulo 
State.
Reddish clays and sands of fluvial-lacustrine origin, 
deposited during times of warm and humid climates, 
dominate the Adamantina Formation. Based primarily on its 
vertebrate fossil content, the Adamantina deposits were 
formed between the Santonian and Maastrichtian.
The osteoderms are subquadrangular in shape, presenting 
the diagnostic ornamentation (coarse and fibrous texture, 
grooves, pits and tiny projections) observed in 
titanosaurid osteoderms already described. The function of 
all of these features is unclear - foramina were probably 
passages for blood vessels and rugosities for anchoring 
the osteoderms. However, both present some 
particularities: the largest one has a prominent ridge 
that separates the dorsal surface into two portions. 
Foramina are sparsely distributed along both surfaces. The 
rugose texture is found around the borders, except in a 
more straight one which presents a pattern of dorsoventral 
laminae. The ventral surface is broken superficially, and 
differs from dorsal surface by having a marked depression 
and a comparatively smoother fibrous texture. The other 
specimen is smaller and thinner. Some dorsal fractures 
permit to observe its cancelous bone internal constitution.
Stereoscopic microscopic analysis of the straight border 
shows no bone fractures, so we interpreted it as an 
articular surface. This indicates that the dinosaur that 
had it may bear dermic plates composed by two or more 
articulating osteoderms, or these dermal bones belonged to 
a different dinosaur to which osteoderms have not been 
described. As this feature has never been reported in a 
Titanosauridae, and the osteoderm, though similar, is 
distinct to the one previously described to Bauru Basin, 
we found no strong basis to assign it to a titanosaurid.
These findings add a new dinosaur locality for the Bauru 
Basin, and comprise the first record of dinosaur 
osteoderms in the Cretaceous of the São Paulo State. - 
(December 20, 2001 ).

Baghai-Riding, Nina L. & Dibenedetto, Joseph N. 2001. An 
unusual dinosaur coprolite from the Campanian Aguja 
Formation, Texas. In: 2001 AAPG Gulf Coast Association of 
Geological Societies meeting; abstracts. AAPG Bulletin. 
85; 9, Pages 1697. 2001. 
The Aguja Formation (Campanian) rivals many other 
Upper Cretaceous localities with regards to the diversity 
of cranial and postcranial elements of dinosaur remains, 
early mammals and palynomorphs. Recently a large, globular 
reptilian multi-tier coprolite (15 cm in length, 9 cm in 
width and 12 cm in height) of an unknown origin, was 
collected from the upper shale member of the Aguja 
Formation in Big Bend National Park, Brewster County, 
Texas. This rare and unusual find provides for the first 
evaluation of a large coprolite of this kind from the 
southwestern United States. The coprolite consists of at 
least ten individual somewhat cylindrical or tubular, 
anisopolar units that curve into half-moon shapes. Organic 
inclusions include inner and outer bark tissue, conifer 
wood fragments, amber resin and pollen grains from 
assorted angiosperms. Inorganic inclusions consist of sand 
grains, manganese oxide, and secondary infillings of 
pyrite, fibrous-like chalcedony, iron-stained carbonate 
and white calcite. The size and structure and contents 
indicate that this coprolite was presumably deposited by 
an herbivorous dinosaur.

Guo Z. & Wang X. 2002. A study on the relationship between 
volcanic activities and mass mortalities of the Jehol 
vertebrate Fauna from Sihetun, western Liaoning, China. 
ACTA PETROLOGICA SINICA. 18(1): 117-125. (JAN 2002). 
Many of the vertebrate fossils have been found in 
recent years in Sihetun, western Liaoning, China, 
including Confuciusornis, Liaoningornis, as well 
as "feathered" theropod dinosaurs, etc. The layers of well-
preserved vertebrate fossils indicate mass mortalities and 
rapid burial of the animal bodies in the lacustrine 
environment, which are coexisting with the intermediate-
acidic tuffs (or ashes) in the field. This paper 
determined the volatile contents of inclusions in 
phenocrysts and matrix glasses, applying the method of 
electron microprobe analysis, from the tuffs and ashes 
coexisting with four typical fossil layers of the well-
preserved vertebrates. The result shows that their 
contents of volatile emitted are higher than those erupted 
from other volcanoes with same compositions worldwide and 
the compositions of volatiles released into atmosphere are 
different, corresponding to the different fossils layers 
in this area. The authors thought that the mass mortality 
events in west Liaoning are mainly due to the significant 
effect of the volatiles and the volcanic dust on climate 
at that time.