This has created an artificially pronounced curvature to the ventral edge of the upper jaw. The original description of Genusauu highlighted that several areas of the iliac blade appeared to be undamaged. Ilokelesia was originally described as a primitive abelisaurian theropod (Coria & Salgado 2000), based primarily on the morphology of the postorbital.
Bara Simla Hill, Jabalpur, Madhya Pradesh, India; 'Carnosaur Bed', 'infratrappean beds' of the Lameta Formation; Maastrichtian, Late Cretaceous (Matley 1921). Bara Simla Hill, Jabalpur, Madhya Pradesh, India; 'Carnosaur Bed', 'infratrappean beds' of the Lameta Formation; Maastrichtian, Late Cretaceous (Huene & Matley 1933). Abelisaurid with: (1) a small fenestra in the skull roof between the prefrontal, frontal, postorbital and lacrimal and (2) a concave dorsal surface of the nasals (modified from Sereno et al.
Putative differences between Velocisaurus and Noasaurus (Bonaparte 1991b; Agnol´ın et al.2003) are based on the misidentified pedal elements (actually manual) in the latter, as mentioned earlier. Missing data comprised as little as 0% of total character codes (Allosaurus, Syntarsus) to over 90% (Genusaurus, Indosaurus, Laevisuchus, Velocisaurus). These included Deltadromeus, all but two of the noasaurids (Masiakasaurus and Noasaurus were retained), and three abelisaurids (Indosaurus, Aucasaurus, and Abelisaurus).
Genyodectes was one of the first South American dinosaur genera to be described (Woodward 1901). Indeed, the morphology of the distal end of the tibia is similar to the condition in Majungasaurus (Carrano 2007). Much of the poor phylogenetic resolution is certainly due to the nature of this analysis.
Redescription of the holotype of Dryptosaurus aquilunguis (Dinosauria: Theropoda) from the Upper Cretaceous of New Jersey. Journal of Vertebrate Paleontology17: 561-573. The second record of the African theropod Elaphrosaurus (Dinosauria, Ceratosauria) from the Western Hemisphere.Neues Jahrbuch f¨ur Geologie und Pal¨aontologie Monatsheft. Overview of the discovery history, taxonomy, phylogeny and biogeography of Majungasaurus crenatissimus (Theropoda: Abelisauridae) from the Late Cretaceous of Madagascar.
The tibia and tarsus in Herrerasauridae (Dinosauria, incertae sedis) and the origin and evolution of the dinosaur tarsus. Taphonomy of the Late Cretaceous dinosaur-bearing beds of the La˜no Quarry (Iberian Peninsula). About the dinosaurs from the Maastricht beds. Quarterly Journal of the Geological Society of London39: 246–253.
Young dinosaurs span the southern landmasses in the mid-Cretaceous. Proceedings of the Royal Society of London, Series B.
List of characters
In most ceratosaurs, the anterior ramus is long but short, usually reaching only the posterior end of the naris. Dorsal nasal surface row of punctures: absent (0), present (1). In most theropods, the dorsal (outer) surface of the snout does not have a prominent foramen. Development of the median parietal plate of the skull: flat, wide (0), narrow, with a sagittal ridge (1). Alignment of the superior temporal fenestrae produces a narrow frontoparietal bridge in most theropods.
In contrast, a distinct sagittal crest is present in abelisaurids due to the exceptional proximity of the upper temporal fenestrae. The nuchal crest is present but low in most theropods, with its height dictated by the development of the dorsal projection of the parietals. Morphology of lacrimal along dorsal orbital margin: flat (0), raised eyebrow or shelf (1). The lacrimal is relatively flat and lacks expansion over the dorsal portion of the orbit in most basal theropods.
In most taxa, it is large or moderate in size and is located at the lateral edge of the quadrate. Medial fossa ventral to occipital condyle: absent (0), present (1). The posterior surface of the basioccipital ventral to the occipital condyle is relatively flat in Herrerasaurus and ceratosaurs. Abdominal pitting on ectopterygoid: absent (0), fossa (1), furrow (2). A fossa is present on the ventral surface.
The anterior end of the spleen tapers to a single point in most theropods, including coelophysoids and tetanurans. In tetanurans and ceratosaurs, the epipophyses are long and extend well beyond the posterior margin of the postzygapophysis. Ventral keel on anterior cervical: present (0), weak or absent (1). The ventral surface of the centrum bears a prominent keel in most primitive theropods, including coelophysoids and Herrerasaurus.
It is relatively small in coelophysoids, Ceratosaurus, and basal tetanurans, extending a distance roughly equal to the depth of the glenoid. In these forms, the depth of the coracoid is significantly more than half its length. Longitudinal rotation of the humeral shaft: absent (0), present (1). In primitive theropods, the long axes of the proximal and distal humeral articular surfaces are nearly parallel.
Development of the medial epicondyle of the femur: rounded (0), ridge (1), long edge (2). Medial epicondylar margin of the femur separating the anterior origin of M. Originally present only as a small, shallow groove along the posterior margin of the medial proximal fibula (although this is slightly deepened in Syntarsus and Liliensternus).
Taxon-by-character matrix for the 21 taxa used in
Width of metatarsal II relative to width of metatarsals III and IV: subequal (0), reduced (1). Metatarsal II is greatly reduced in shaft diameter relative to III and IV in Noasaurus, Velocisaurus, and Masiakasaurus, and slightly reduced in Elaphrosaurus and possibly Deltadromeus. Proportion of distal end of metatarsal IV: wider than high (0), higher than wide (1). The distal end of metatarsal IV is relatively wide and exceeds its height (or dorsoventral depth) in primitive theropods and other dinosaurs. In most neotheropods, the reverse proportions are evident: the distal end is taller (deeper) than wide.
It has also been noted that Masiakasaurus and Deltadromeus appear to share an unusually narrow distal metatarsal IV (Wilson et al. 2003; Sereno et al. 2004), but the high degree of variation and lack of associated material from Masiakasaurus makes this difficult to evaluate. Antarctometatarsus: absent (0), present (1). It has long been noted that several groups of coelurosaurs display a derived metatarsus morphology, with metatarsal III reduced proximally and 'sandwiched' between metatarsals II and IV. Most theropods retain a metatarsus, with III having the largest proximal area of the central three metatarsals.
However, in most abelisauroids the 'opposite' condition prevails, with II and IV being further reduced relative to III. The proximal surface of metatarsal III is significantly increased in both anteroposterior and mediolateral dimensions, a condition originally termed an 'antarctometatarsus' by Holtz (see Carrano et al. 2002). Morphology of lateral and medial grooves on pedal-ungual phalanges: single (0), double (1). So-called 'blood' grooves are present on all theropod pedal-ungual phalanges.
Primitively, a groove is present on each side (lateral and medial) of the ungual, running approximately parallel to the dorsal surface. Abelisauroids (but not Ceratosaurus) are unique in having two widely spaced grooves on either side of the ungual, which converge at the tip of the bone (Sampson et al. Other theropods may show evidence of two grooves, but these are invariably restricted to the most proximal only part of the ungual.
Mediolateral symmetry II. pedal toe: symmetrical (0), asymmetrical (1). In most theropods, including primitive forms, II. pedal toe in cross-section approximately symmetrical, triangular toe. Length of phalanges of pedal toe I-1+ I-2 relative to III-1: greater (0), less or equal (1). Pedal toe I gradually decreases in non-avian theropods. It undergoes retroversion only when it is deep in the Aves and retains its primitive articulation near the tarsus along the posteromedial shaft of metatarsal II.
Theropod specimens examined