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Here's some new refs I found at the library that
haven't been mentioned yet.
Schulp, Hanna, Hartman and Jagt, 2000. A Late
Cretaceous theropod caudal vertebra from the Sultanate of Oman. Cretaceous
Research 21 851-856.
Theropoda indet.
Maastrichtian, Late Cretaceous
Al-Khod Conglomerate Formation, Oman
Material- (SQU-2-7, Sultanate Qaboos University
coll.) proximal caudal centrum (92 mm)
Description-
It's length is estimated at 6-7
meters.
The centrum is platycoelous or slightly
amphicoelous and subcircular posteriorly (111 mm tall, 105 mm wide). There
are no pleurocoels, a slight chevron facet and a prominent ventral ridge.
The neural canal is 18 mm wide, the ventral edge is deeply concave.
Relationships-
This is a fairly standard theropod caudal vertebra
in most ways. The subcircular amphicoelous or platycoelous centrum with a
deeply concave ventral edge and no pleurocoels is seen in the majority of
theropods. Only "Capitalsaurus", Sinraptor dongi, alvarezsaurids and
possibly Bagaraatan are known to have a single ventral ridge. Those of
alvarezsaurids are strongly procoelous, while the other taxa have centra much
taller than wide. Unfortunately, the fragmentary material does not allow
identification more precise than Theropoda indet..
Buffetaut, Mechin and Mechin-Salessy, 2000. An
archaic bird (Enantiornithes) from the Upper Cretaceous of Provence (Southern
France). Comptes Rendus de l'Academie des Sciences 331
557-561.
Pygostylia indet.
Early Maastrichtian, Late Cretaceous
Bastide-Neuve, Provence, France
Material- (Mechin coll. no. 606) tibiotarsus (132
mm)
Description-
The tibiotarsus has a craniomedial cnemial
crest and is transversely wide proximally, although this may be due to
crushing. The distal condyles are asymmetrical (medial condyle larger),
separated by a distinct groove that ends in a fossa. The cranial surface
of the medial condyle is flat. The astragalocalcaneum is not fused to the
tibia. There is a tubercle on the ascending process of the
astragalocalcaneum.
Relationships-
The tubercle on the ascending process and
reduced fibula are pygostylian characters. Although uncommon, lack of
fusion between the astragalocalcaneum and tibia is known in pygostylians
(Vorona, Iberomesornis). The large medial condyle and lack of two distinct
cnemial crests exclude it from the Ornithurae. The narrow, deep
intercondylar groove is known in both enantiornithines and ornithurines
(Apsaravis). The flat cranial surface on the medial condyle has been
claimed to be an enantiornithine synapomorphy, but has not been examined
closely. Although Buffetaut et al. use many of the above characters to
place this taxon in the Enantiornithes, Norell and Clarke (2001) show that these
are actually characteristic of more inclusive groups and that enantiornithines
cannot be identified based on tibial characters. Thus, this specimen seems
to represent a non-ornithurine pygostylian, though not neccessarily an
enantiornithine.
Clark, Sues and Berman, 2000. A new specimen of
Hesperosuchus agilis from the Upper Triassic of New Mexico and the
interrelationships of basal crocodylomorph archosaurs. Journal of Vertebrate
Paleontology 20(4) 683-704.
Although mainly about sphenosuchians (which are
found to be monophyletic by the way), this article does include something of
interest to dinosaur fans. Trialestes romeri (originally named
Triassolestes by Bonaparte in 1963, but that was preoccupied) from the
Ischigualasto Formation (mid-Carnian, Late Triassic) of Argentina may be
dinosaurian. The holotype (PVL 2561) consists of a partial skull,
cervicals, caudals, scapula, humerus, radius, ulnae, radiale and ulnare.
PVL 2559 was referred to the species and includes a partial pes (the cervicals,
sacrals, pubis and astragalus originally included in the specimen are
lost). Bonaparte (1978) later referred another specimen (PVL 3889) to the
taxon. This consists of vertebrae, forelimb without carpus, pelvis and
hindlimb. The taxon is generally thought to be crocodylomorph based on the
elongate radiale and ulnare found in the holotype. PVL 3889 however, has
several characters seen in dinosaurs but not crocodylomorphs- laterally
excavated vertebral centra; perforated acetabulum; well-developed supracetabular
crest; distinct inturned femoral head; mesotarsal ankle; functionally tridactyl
pes. The authors find most of the characters uniting PVL 2561 and PVL 3889
are symplesiomorphic, but that they both have very elongate forearms (1.12 times
humeral length). This means either PVL 2561 is crocodylomorph and PVL 3889
is dinosaurian, but they both developed elongate forearms in parallel; or that
Trialestes is dinosaurian (based on parsimony) and has a crocodylomorph-like
carpus. Very interesting.....
Fiorillo and Gangloff, 2000. Theropod teeth from
the Prince Creek Formation (Cretaceous) of Northern Alaska, with speculations on
Arctic dinosaur paleoecology. Journal of Vertebrate Paleontology 20(4)
675-682.
This article shows that Troodon is the most common
theropod in the Prince Creek Formation and that Ricardoestesia is absent.
The tooth (AK211-V-001) referred to Alectrosaurus by Gangloff (1998) is actually
from Dromaeosaurus, as it is strongly compressed laterally without blood
grooves. This means there are no records of Alectrosaurus in
Alaska.
Mickey Mortimer
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