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New References



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