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Ford and Chure, 2001. Ghost lineages and the
paleogeographic and temporal distribution of tyrannosaurids. JVP 21(3)
50A-51A,
A great summary of tyrannosaurid specimens,
including early taxa. There are too many specimens to list, but the two
most interesting to me are-
Tyrannosauroid tooth (WDIS 539) from the Morrison
Formation of Wyoming (Bakker, 1998). Tyrannosaurus langingi (Zhao, 2986)
known from teeth (IVPP coll.) from the Berriasian-Hauterivian Upper Chingshing
Formation of Yunnan, China.
I have never heard of the latter species, not to be
confused with Tyrannosaurus lanpingensis (Yeh, 1975).
Bertini and Franco-Rosas, 2001. Scanning electron
microscope analysis on Maniraptoriformes teeth from the Upper Cretaceous of
Southeastern Brazil. JVP 21(3) 33A.
Over two-hundred teeth from the Bauru Group
(Adamantina and Marilia Formations) of Brazil were examined and found to belong
to dromaeosaurids (including velociraptorines), troodontids, Richardoestesia
gilmorei and four new taxonomic groups.
Headden, 2001. Jaw function in Oviraptoridae
(Dinosauria: Theropoda). JVP 21(3) 59A.
Oviraptorid jaws have many specializations,
somewhat similar to dicynodonts and testudinines. They are comparable to
dicynodonts and testudines, but have several characters distinguishing them from
other theropods. These include a rasp-like ventral secondary palatal
surface, ventrally displaced throat and fused symphyses.
Kobayashi, Azuma, Dong and Barsbold, 2001. Bonebed
of a new gastrolith-bearing ornithomimid dinosaur from the Upper Cretaceous
Ulansuhai Formation of Nei Mongol Autonomous Region, China. JVP 21(3)
68A-69A.
More than twelve nearly complete skeletons of a new
ornithomimid from the Ulansuhai Formation (Santonian?) of China.
Diagnostic characters include- no depression on ventral scapular edge;
posteriorly located coracoid tubercle; transversely compressed manual unguals;
deep femoral intercondylar groove; straight pubic shaft; straight ventral pubic
foot border. The subadult skull is 183 mm long, hyoids are preserved,
there are six sacral vertebrae and no ossified sternum. Fourteen rows of
gastralia are present, the scapula is 91% of humeral length, the acromion is
weaker than Struthiomimus or Gallimimus and the ulna is bowed toward the
radius. There are three carpals- the intermedium, distal carpal I and
distal carpal II. Metacarpal I is 82% of metacarpal II, while metacarpal
III is 94%. A cladogram was presented, using 26 characters and ten
taxa. The topology was-
|-Harpymimus
`-+-Pelecanimimus `-+-Garudimimus `-+-Archaeornithomimus `-+-new taxon `-+-+-Anserimimus | `-Gallimimus `-+-Struthiomimus `-+-Ornithomimus `-Dromiceiomimus Both the character list and matrix were
present. Unfortunately, few nodes are well supported. Harpymimus is
quite well separated from the rest, which may not be surprising.
Toothlessness distinguishes ornithomimids, while only the miscoded
"arctometatarsus" keeps Archaeornithomimus above Garudimimus (possibly
indicating they are synonymous, as previously suggested). The new specimen
does seem to clade strongly with "derived ornithomimids" though, as shown by
five characters missing in Garudimimus or Archaeornithomimus. The
relatively short first metacarpal keeps the new taxon away from the other
taxa. I don't think the three characters grouping Anserimimus with
Gallimimus are that great, considering my brief examination concluding it is
closer to North American taxa, especially Ornithomimus. One character
groups North American taxa together (unknown in Anserimimus), while two place
Ornithomimus with Dromiceiomimus. The latter is interesting in regard to
recent suggestions they are congeneric.
Ryan, Currie and Russell, 2001. New material of
Avimimus portentosus (Theropoda) from the Iren Debasu Formation (Upper
Cretaceous) of the Erenhot Region of Inner Mongolia. JVP 21(3) 95A.
This describes several avimimid elements from the
Iren Debasu Formation (Campanian?) of China. The orbital margin of a
frontal (TMP 92.302.104) is difficult to compare to A. portentosus, but is
similarily bulbous over the orbits. There is an anterior dorsal (TMP
92.302.140) that resembles the second of Avimimus, but has a shorter
hypapophysis and more ventrally placed parapophyses. Another vertebra (TMP
92.302.344) was not identified specifically, but appears to be a mid
caudal. There seem to be two small lateral foramina, the centrum is not
quadrangular in section and a low neural spine is present. A partial fused
scapulocoracoid (TMP 92.302.116) is shown, with a ventrally directed glenoid and
low coracoid tubercle. It is very comparable to the holotype, but more
incomplete, lacking the ventral coracoid tip, most of the anterior edge and all
but the base of the scapular shaft. A proximal humerus (TMP 92.302.117) is
extremely similar to the holotype, differing only in minor proportional
details. Both proximal (TMP 92.302.149) and distal (TMP 92.302.110)
femoral ends are known. The former differs from the holotype in the more
lateromedially compressed greater trochantor and less prominent anterior
trochantor in proximal view. The distal femur has less extensive articular
surfaces in anterior view and a less prominent lateral condyle. In distal
view, it is less convex anteriorly. A proximal tibia (TMP 92.302.150) is
quite different from A. portentosus, having a bulbous lateral condyle, less
dorsally projected cnemial crest, and small posterior process in proximal
view. The proximal metatarsus (TMP 92.302.102) is very similar anteriorly
and posteriorly, but is differently shaped proximally, being
parallelagram-like. Another metatarsus (AMNH 6755), this one complete
except for the proximal portion of metatarsal III, is quite unique. It was
found in the Central Asiatic Expeditions of 1923 along with another third
metatarsal (AMNH 6764). This metatarsus is arctometatarsalian, but the
third metatarsal extends up 90% of the metatarsal length in anterior view (and
almost as much posteriorly). This contrasts with 45% in A.
portentosus. This metatarsus is less slender than the latter, with a more
reduced fourth metatarsal and no fifth metatarsal fused to it. I'm not
altogether convinced this is an avimimid and not a caenagnathid, for
instance. Two pedal unguals (TMP 92.302.119A and B) are quite odd.
They are markedly asymmetrical, having smaller lateral halves with much higher
grooves on that side. Although there are twelve elements in the RTMP
collections labeled Avimimidae, only two can certainly be assigned to that
taxon. One, TMP 98.68.22, is a distal third metatarsal from the Dinosaur
Park Formation (Judith River Group). The other (TMP 98.8.28) is a second
metatarsal that is unfused proximally, unlike A. portentosus. It is from
the Scollard Formation. Although the authors assign at least the Iren
Debasu material to A. portentosus, I'm not so certain. Those who want
photos of the various remains, ask me offlist.
Buckley and Ott, 2001. A new specimen of
alvarezsaurid from the Late Cretaceous Hell Creek Formation. JVp 21(3)
36A-37A.
A third metatarsal from a mononykine alvarezsaurid,
discovered in the Hell Creek Formation (Late Maastrichtian) of Montana.
It's similar to Mononykus, but not as laterally compressed in the middle and has
a sharper plantar ridge. It would be interesting to compare to
"Ornithomimus" minimus. Those who want a photo, ask offlist.
Suzuki, Chiappe, Dyke, Watabe, Barsbold and
Tsogtbaatar, 2001. A new specimen of Shuvuuia deserti from the Late Cretaceous
Djadokhta Formation of Mongolia. JVP 21(3) 107A.
A new specimen of Shuvuuia (MPD 100/120) from the
Djadokhta Formation (Campanian?) of Mongolia is described. It includes
skull fragments including most of the mandibles, about seven cervicals, about
nine dorsals, several dorsal ribs, what may be part of a sacrum, about twenty
caudals, scapula, manual phalanges, femora, tibiae, fibula and pedes. The
caudals are slender, shortening distally and without elongate
prezygopophyses. Over ten were missing, bringing the total to over
thirty. The manual elements show Shuvuuia had small digits II and
III. Manual digit II has two phalanges, the second one shortest, plus an
ungual. The third digit has at least one phalanx and an ungual. The
unguals and slender and slightly curved. Phalanx I-1 isn't as modified as
Mononykus', being more slender and symmetrical. The first manual ungual is
less recurved with a less concave proximal articular surface. The
astragalus seems fused to the tibia and the proximal end is very different from
Mononykus, being more primitive looking. It has a proximodistally shorter
cnemial crest and more posteriorly placed lateral condyle. The metatarsus
is very elongate (8% longer than the femur) with a first digit more slender than
Mononykus. It is articulated and apparently not retroverted. Two of
Sereno's (2000) characters connecting alvarezsaurids to ornithomimosaurs were
rejected. First, "Manual I-1 phalanx, dorsomedial tubercle present", the
tubercle of alvarezsaurids is actually dorsolateral. Also, "Manual
unguals, position of flexor tubercles- displaced distally", Suzuki et al. argue
alvarezsaurids lack any manual flexor tubercles. Alvarezsaurus has a keel
in the appropriate position however, placed distally, so don't think it
appropriate to reject this character yet. I was able to see the huge paper
describing this specimen and dealing with all of Sereno's "ornithomimoid"
characters, but had very little time to look at it. It will be out next
year perhaps, in the LACM publication Contributions to Science. I can't
wait. Anyone who wants photos of the specimen, ask me
offlist.
Kirkland and Wolfe, 2001. A therizinosaurid
(Dinosauria: Theropoda) braincase from the Middle Turonian (Cretaceous) of North
America. JVP 21(3) 68A.
Describes the braincase of Nothronychus, which is
79mm across the paraoocipital processes. Like Erlikosaurus, the
basisphenoid is very pneumatized, the basipterygoid processes and basitubera are
indistinct and the paraoccipital processes are hollow. The occipital
condyle is wider than tall, and the foramen magnum is 22% wider than the
occipital condyle. It differs from Erlikosaurus in having shorter
paraoccipital processes and a more horizontally oriented supraoccipital without
a nuchal crest.Those who want photos, contact me offlist.
Gillette, Albright, Titus and Graffam, 2001.
Discovery and paleogeographic implications of a therizinosaurid dinosaur from
the Turonian (Late Cretaceous) of Southern Utah. JVP 21(3) 54A.
A new segnosaur from the Tropic Shale (Early
Turonian) includes several dorsal vertebrae, dorsal ribs, sacrum, caudal
vertebrae, chevrons, ilia, pubes, ischia, femora, tibiae, fibulae, astragali,
six metatarsals and phalanges. It has an opisthopubic pelvis and
tetradactyl pes.
Gishlick, 2001. Evidence for muscular control of
avian style automatic extension and flexion of the manus in the forearm of
maniraptors. JVP 21(3) 54A.
Three muscles are involved with the coordinated
folding of the forearm and metacarpus in birds- m. extensor metacarpi
radialis (EMR), m. flexor metacarpi ulnaris (FMU) and m. extensor metacarpi
ulnaris (EMU). These insert in a particular way in birds to allow "two
joint" muscles that can automatically flex and extend. Caudipteryx,
Deinonychus, Velociraptor and Archaeopteryx are shown to have osteological
correlates for these insertions, showing they had an avian-like wing-folding
mechanism.
Schweitzer, Jackson, Chiappe, Calvo and Rubilar,
2001. Cretaceous avian eggs and embryos from Argentina. JVP 21(3)
99A.
Eggs with embryos have been found in the Rio
Colorado Formation of Argentina. The remains indicate a basal bird, such
as an enantiornithine, but the eggs have a prismatic trilaminate microstructure
characteristic of neognaths.
Lamb, 2001. Dinosaur egg with embryo from the
Cretaceous (Campanian) Mooreville Chalk Formation, Alabama. JVP 21(3)
70A.
A spherical egg with heavy tubercles and an
ornithischian embryo. It belongs to the Spheroolithidae.
Nesbitt, 2001. New fossil vertebrate material from
the Holbrook Member, Moenkopi Formation (Middle Triassic) from Northern Arizona.
JVP 21(3) 83A.
Includes a partial pubis perhaps from a
herrerasaurid. Would be remarkable from the Middle Triassic. It did
look rather similar to Staurikosaurus...
Martinez, Garcia-Ramos, Pinuela, Lires and Luna,
2001. Dinosaur remains from the principality of Asturias, Spain. JVP 21(3)
78A.
Kimmeridgian remains from the Vega and Lastres
Formations. Includes- large theropod proximal caudal; "megalosauroid"
teeth; coelurosaur teeth with constricted bases and anterior serrations confined
to the distal third; camarasaurid tooth and caudal vertebra; peg-like tooth with
diplodocid-like wear facet, but resembling brachiosaurids.
Kurzanov, Efimov and Gubin, 2001. Jurassic
dinosaurs of Yakutia. JVP 21(3) 70A.
Late Jurassic beds in Yakutia (Russia) have yielded
bones of Allosaurus, coelurosaurs, Camarasaurus and Stegosaurus.
Burge and Bird, 2001. Fauna of the Price River II
Quarry of Eastern Utah. JVP 21(3) 37A.
Dinosaurs from the Ruby Ranch Member of the Cedar
Mountain Formation. Four brachiosaurs are represented by cervicals,
dorsals, sacrals, caudals, a scapula, limb elements, medipodials, a phalanx
and unguals. Two are adults and one is a juvenile. Two large
conspecific ankylosaurid individuals, complete with skulls, are present.
Fragmentary remains of a nodosaurid and iguanodont are also known.
Leshchinskiy, Voronkevich, Fayngertz, Maschenko,
Lopatin and Averianov, 2001. Early Cretaceous vertebrate locality Shestakovo,
Western Siberia, Russia: A refugium for Jurassic relicts? JVP 21(3)
73A.
Remains include possible tyrannosaurids,
troodontids, "velociraptorines", a bird, titanosaurians and Psittacosaurus
sibiricus. The latter is a species I have not heard of, but is undoubtedly
the same as- "New Psittacosaurus species to be described from the
Lower Cretaceous of the eastern Russia, specimen discovered in the Moscow
University collection but unlikely to be described in the near future (R. E.
Molnar pers comm. to Olshevsky 1996)", which is in my files. It is
apparently known from at least two skeletons and is "the largest and one of the
most derived species of the genus".
Malkani, Wilson and Gigerich, 2001. First dinosaurs
from Pakistan. JVP 21(3) 77A.
Remains from the Maastrichtian Pab Formation of
Pakistan. Cranial, vertebral and appendicular remains of a saltasaurid, as
shown by the procoelous caudal centra, large olecranon process and biconvex
first caudal centrum. It is differentiated from other taxa by the short
broad dorsal centra and very slender limb proportions.
Williamson and Carr, 2001. Dispersal of
pachycephalosaurs and tyrannosauroids between Asia and North America. JVP 21(3)
114A.
Ornatotholus is said to be a juvenile Stegoceras,
agreeing with Sullivan (2000). Siamotyrannus is not considered a
tyrannosauroid. A phylogenetic analysis using 106 characters and 16 taxa
was performed, resulting in the following topology-
|-Dryptosaurus
`-+-Alabama taxon `-+-New Mexico taxon `-+-|-Albertosaurus libratus | |-Albertosaurus sarcophagus | `-Albertosaurus sp. nov. `-+-Daspletosaurus `-+-Tyrannosaurus bataar `-Tyrannosaurus rex Note Dryptosaurus is a tyrannosauroid, as in
Holtz's new analysis (coming in the next Details on SVP). The Alabama
taxon (RMM 6670) is from the Campanian Demopolis Formation, while the New Mexico
taxon (NMMNH P-27469) is from the Late Campanian Kirtland Formation. In
the references was the following- Carr and Williamson, in prep. Phylogeny of the
Tyrannosauroidea. Photos of the skulls of these new taxa are available to
those who contact me offlist.
Mickey
Mortimer |