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The dinosaur fauna from the Guimarota mine
... Reports of dromaeosaurid-like teeth from the Morrison Formation have been rare, with only two teeth illustrated, from the Dry Mesa Quarry in western Colorado and the Warm Springs Ranch site in northern Wyoming (Britt, 1991;Ikejiri and others, 2006). The occurrence of dromaeosaurid (or at least dromaeosaurid-like) teeth in at least three deposits in the Morrison Formation, plus a number of dromaeosaurid teeth in the Late Jurassic of Portugal, Spain, Germany, Ethiopia, and China (Zinke, 1998;Rauhut, 2000;Van Der Lubbe and others, 2009;Han and others, 2011;Hall and Goodwin, 2011), suggests that this family was rare but certainly present in many areas of the globe during the Late Jurassic. In the Morrison Formation, isolated, partial bones of possible dromaeosaurs were reported by Jensen and Padian (1989), but those are the only nontooth evidence of the family in the formation. ...
... A small (4.1 mm crown height) and laterally compressed tooth (figures 13C to 13D) differs from the dromaeosaurid tooth type described above in having a relatively taller crown, in being less recurved, and in having finer serrations on the distal carina (8/mm) that are shorter with more rectangular and blunt apical profiles. In these characteristics, the tooth type is roughly similar to many teeth assigned to Richardoestesia (Currie and others, 1990), a taxon which has been identified from the Late Jurassic of Portugal (Rauhut, 2000;Mateus, 2006;Malafaia and others, 2017). Although the Little Houston Quarry tooth is similar to some illustrated teeth of Cretaceous Richardoestesia in being somewhat recurved (Currie and others, 1990), a few Cretaceous and Jurassic specimens are relatively tall and less recurved (see figure 6 in Zinke, 1998; see figure 11.9 in Rauhut, 2000;Longrich, 2008). ...
... In these characteristics, the tooth type is roughly similar to many teeth assigned to Richardoestesia (Currie and others, 1990), a taxon which has been identified from the Late Jurassic of Portugal (Rauhut, 2000;Mateus, 2006;Malafaia and others, 2017). Although the Little Houston Quarry tooth is similar to some illustrated teeth of Cretaceous Richardoestesia in being somewhat recurved (Currie and others, 1990), a few Cretaceous and Jurassic specimens are relatively tall and less recurved (see figure 6 in Zinke, 1998; see figure 11.9 in Rauhut, 2000;Longrich, 2008). Larson and Currie (2013) demonstrated the difficulties, in many cases, of distinguishing species of Richardoestesia and other small Cretaceous theropod taxa, based on teeth, and this indirectly implies there may be difficulty in referring isolated teeth from other times or geographical areas to the genus. ...
The Little Houston Quarry in the Black Hills of Wyoming contains the most diverse vertebrate fauna in the Morrison Formation (Upper Jurassic) north of Como Bluff and the second-most diverse in the entire formation, after Reed’s Quarry 9. The deposit was an occasionally reactivated abandoned river channel, in interbedded green mudstone and laminated green-gray siltstone above a channel sandstone. The dinosaur material is densely distributed and is disarticulated to articulated, with several associated skeletons. The biota contains charophytes, horsetails, a possible seed fern, possible conifers, gastropods, two types of unionoid bivalves, diplostracans (“conchostracans”), a malacostracan, ray-finned fish, lungfish, a frog, salamanders, two types of turtles, rhynchocephalians, a lizard, choristoderes, two types of crocodyliforms, a pterosaur, Allosaurus and several types of small theropods including Tanycolagreus? and probable dromaeosaurids, numerous Camarasaurus and a diplodocine sauropod, a stegosaur, the neornithischian Nanosaurus, and the mammals Docodon, Amblotherium, and a multituberculate. Among these taxa, one of the unionoid bivalves, an atoposaurid crocodyliform, and the species of Amblotherium, which appear to be new and unique to the locality so far. The Docodon material may represent the first occurrence of D. apoxys outside of its type area in Colorado. Additionally, small, unusual theropod tooth types reported here may represent the first Late Jurassic occurrence of cf. Richardoestesia in North America and a possible abelisauroid, respectively.
... Knoll & Ruiz-Omeñaca (2009) reported the presence of three Velociraptorinae morphotypes, but this should be considered cautiously owing to the difficulty in identifying a theropod subfamily from only isolated teeth ( Hendrickx et al. 2015). A large part of these taxa could rather be related to Dromaeosauridae, which would be one of the earliest occurrences of this group, together with the teeth from the Upper Jurassic of Guimarota (Rauhut, 2000) and the specimens from the Barremian of China ( Norell & Makovicky, 2004). Isolated teeth tentatively attributed to dromaeosaurid-like theropods are reported from the Middle Jurassic of England ( Metcalf et al. 1992), but their identification is uncertain and no fossil bones have been recovered from the Middle Jurassic so far. ...
... The faunal assemblage from Guimarota shows affinity with that of the KM fauna at higher taxonomic levels. The two faunas share hybodont selachians (Kriwet, 2000(Kriwet, , 2004), pycnodontiform actinopterygians (Kriwet, 2000(Kriwet, , 2002), albanerpetontids (Wiechmann, 2000;Gardner et al. 2003), atoposaurids (Schwarz & Salisbury, 2005), teleosaurids (Schwarz, 2002), ornithischian dinosaurs (Zinke, 1998;Rauhut, 2000Rauhut, , 2001), dromaeosaurid theropods (Zinke, 1998;Rauhut, 2000) and dryolestid and zatherian mammals (Martin, 1999(Martin, , 2000(Martin, , 2001(Martin, , 2002). Considering all these taxa together, this faunal association is consistent with a possible Late Jurassic age for the KM fauna, although the high taxonomic-rank affinity with Guimarota does not permit a definitive conclusion. ...
... The faunal assemblage from Guimarota shows affinity with that of the KM fauna at higher taxonomic levels. The two faunas share hybodont selachians (Kriwet, 2000(Kriwet, , 2004), pycnodontiform actinopterygians (Kriwet, 2000(Kriwet, , 2002), albanerpetontids (Wiechmann, 2000;Gardner et al. 2003), atoposaurids (Schwarz & Salisbury, 2005), teleosaurids (Schwarz, 2002), ornithischian dinosaurs (Zinke, 1998;Rauhut, 2000Rauhut, , 2001), dromaeosaurid theropods (Zinke, 1998;Rauhut, 2000) and dryolestid and zatherian mammals (Martin, 1999(Martin, , 2000(Martin, , 2001(Martin, , 2002). Considering all these taxa together, this faunal association is consistent with a possible Late Jurassic age for the KM fauna, although the high taxonomic-rank affinity with Guimarota does not permit a definitive conclusion. ...
The Middle Jurassic – Early Cretaceous period witnessed the emergence of some major representatives of modern continental vertebrate groups (stem lissamphibians, squamates, therian mammals and birds) and angiosperms, at a time when fragmentation of Pangaea was underway. The successive Moroccan microvertebrate faunas of Ksar Metlili (?Berriasian) and Guelb el Ahmar (Bathonian) from the Anoual Syncline significantly improve our poor knowledge of Gondwanan and especially African palaeobiodiversity at this time. They are among the richest known from the Mesozoic of Gondwana, and are well placed in northwestern Africa to record faunal interchanges with Laurasia. Here we focus on the Ksar Metlili fauna, first documented in the 1980s and most recently resampled in 2010, which produced 24 541 microremains representing 47 species of 8 main groups (Chondrichthyes, Actinopterygii, Sarcopterygii, Lissamphibia, Lepidosauromorpha, Testudinata, Archosauromorpha and Synapsida). It includes remarkable taxa: the oldest stem boreosphenidan mammals from Gondwana, probably some of the last non-mammaliaform cynodonts, a basal ornithischian, possibly freshwater teleosaurid crocodylomorphs, and some of the rare occurrences of choristoderes and albanerpetontids in Gondwana. Comparison of the Ksar Metlili fauna with that of Guimarota (Kimmeridgian, Portugal) further provides evidence of numerous shared taxa of Laurasian affinities, in contrast to the occurrence of few taxa with Gondwanan affinities. This suggests complex palaeobiogeographical relationships – implying both vicariance and dispersal events – of North Africa within Gondwana at the Jurassic–Cretaceous transition. Finally, the faunal similarities with the Guelb el Ahmar fauna question the Cretaceous age of the Ksar Metlili fauna, suggesting an alternative possible Late Jurassic age.
... In the fauna of the Morrison Formation, small theropods are mainly represented by coelurosaurs, such as Coelurus and Ornitholestes (Marsh, 1879;Osborn, 1903;Ostrom, 1980), tyrannosauroids (Madsen, 1974;Foster & Chure, 2000), and maniraptorans (Jensen & Padian, 1989;Chure, 1994Chure, , 1995. Likewise, Late Jurassic small theropod faunas from Europe include the basal coelurosaur Compsognathus (Wagner, 1861;Bidar, Demay & Thomel, 1972;Zinke, 1998), tyrannosaurs (Zinke, 1998;Rauhut, 2000Rauhut, , 2003b, and a variety of maniraptorans (Zinke, 1998;Rauhut, 2000). The only ceratosaurs identified from the Late Jurassic of the Northern Hemisphere so far are the medium-sized basal taxon Ceratosaurus (Marsh, 1884;Madsen & Welles, 2000;Antunes & Mateus, 2003) and a close relative of the medium-sized basal abelisauroid Elaphrosaurus (Galton, 1982;Chure, 2001). ...
... In the fauna of the Morrison Formation, small theropods are mainly represented by coelurosaurs, such as Coelurus and Ornitholestes (Marsh, 1879;Osborn, 1903;Ostrom, 1980), tyrannosauroids (Madsen, 1974;Foster & Chure, 2000), and maniraptorans (Jensen & Padian, 1989;Chure, 1994Chure, , 1995. Likewise, Late Jurassic small theropod faunas from Europe include the basal coelurosaur Compsognathus (Wagner, 1861;Bidar, Demay & Thomel, 1972;Zinke, 1998), tyrannosaurs (Zinke, 1998;Rauhut, 2000Rauhut, , 2003b, and a variety of maniraptorans (Zinke, 1998;Rauhut, 2000). The only ceratosaurs identified from the Late Jurassic of the Northern Hemisphere so far are the medium-sized basal taxon Ceratosaurus (Marsh, 1884;Madsen & Welles, 2000;Antunes & Mateus, 2003) and a close relative of the medium-sized basal abelisauroid Elaphrosaurus (Galton, 1982;Chure, 2001). ...
Small theropod post-cranial material from Tendaguru, Tanzania, the only known Late Jurassic theropod locality in the Southern Hemisphere, is reviewed. Material originally described as ‘coelurosaurs’ includes at least one taxon of basal tetanuran and one taxon of small abelisauroid. Together with the abelisauroid Elaphrosaurus and the presence of a larger ceratosaur in Tendaguru, this material indicates that ceratosaurs were an important faunal element of Late Jurassic East African theropod faunas. One bone furthermore shares derived characters with the holotype of the poorly known Middle Jurassic Australian theropod Ozraptor and allows the identification of the latter as the oldest known abelisauroid, thus indicating an early divergence of ceratosaurids and abelisauroids within ceratosaurs. Abelisauroids might have originated in Gondwana and represent important faunal elements of Cretaceous Gondwanan theropod faunas in general.
... In the study that described this taxon, Sereno et al. (1996) included a small phylogenetic analysis which placed D. agilis as a coelurosaur. Later, D. agilis was recovered as sister to Ornithomimosauria (Rauhut, 2000(Rauhut, , 2003. Other studies placed this taxon in Ceratosauria (Carrano & Sampson, 2002;Sereno et al., 2004;Carrano & Sampson, 2008;Pol & Rauhut, 2012). ...
The Continental African abelisauroid theropod dinosaur fossil record from the Jurassic-Cretaceous periods is becoming increasingly better understood, and offers great insight into the evolution and biogeography of this long-lived group of carnivores. Abelisauroidea is among the most familiar groups of theropod dinosaurs from Gondwana, with fossil records in South America, Australia, India and Africa, along with Europe. The objective of the present study is to review the fossil record of abelisauroids in continental Africa. Based on the literature and records from the online databases “The Paleobiology Database” and “The Theropod Database”, we review the distribution of these theropods in Africa and comment on their evolution. The African continent is a major region of importance when it comes to 26 Abelisauroidea fossil findings, including records of both major subdivisions of the clade: the Abelisauridae and Noasauridae families. The oldest Abelisauroidea fossil record found in Africa dates from the Late Jurassic, while the final records date from the end of the Cretaceous. This indicates that clade was the longest surviving lineage of the large theropods of Africa, and they filled a variety of ecological roles, including apex predators, at the end of the Cretaceous, when tyrannosaurids occupied similar niches in the northern continents.
... The Upper Jurassic fossil record of theropods from the Lusitanian Basin also includes some isolated teeth assigned to abelisaurids (Hendrickx and Mateus 2014b). Small-sized and more derived theropods (six more taxa) have also been described, such as Tyrannosauroidea (Rauhut 2000) and a great diversity of maniraptoran coelurosaurs, mostly identified on the basis of isolated teeth, including Dromaeosauridae, Richardoestesia, velociraptorine dromaeosaurids, compsognathids, and troodontids (Zinke 1998;Hendrickx and Mateus 2014b;Malafaia et al. 2017a). ...
Jurassic units of the Lusitanian Basin, housed at the Sociedade de História Natural in
Torres Vedras, are here described. They were collected from three different geological
formations, the Praia da Amoreira‐Porto Novo (upper Kimmeridgian) and the Alcobaça
(Kimmeridgian‐lower Tithonian) formations in the Consolação Sub‐basin and the
Freixial Fm. (middle‐upper Tithonian) in the Turcifal Sub‐basin. Four different theropod
morphotypes are identified as follows: cf. Jurabrontes isp., Megalosauripus cf. transjuranicus, Grallatoridae indet. and an indeterminate morphotype (Theropoda indet.)
that have affinities with other Therangospodus‐like tracks described in Europe. An
indeterminate sauropod track is also identified. These five morphotypes suggest high
saurischian dinosaur ichnodiversity, similar to that seen in other European Late Jurassic
areas (e.g. the Swiss Jura Mountains), but represent just a portion of the higher
diversity exhibited by the osteological record in the Lusitanian Basin. Further, one
crocodylomorph pes track identified as Crocodylopodus isp. and swim tracks assigned
to Characichnos isp., possibly also produced by crocodylomorphs, are also identified.
The newly identified ichnotaxa, together with the older and other recent identifications,
indicate ichnodiversity comparable with the richest coeval Upper Jurassic units.
... The Upper Jurassic of Portugal yields abundant vertebrate remains, notably vertebrate microfossils as illustrated by the Guimarota Mine assemblage (Martin & Krebs, 2000). One of the more diverse clades is the archosaurs, with more than 30 species of dinosaurs described to date (Rauhut, 2000;Antunes & Mateus, 2003;Mateus et al., 2009;Escaso et al., 2014;Hendrickx & Mateus, 2014;Tschopp et al., 2015;Malafaia et al., 2018;Mocho et al., 2019). Other archosaurs are less well-studied and, to date, only six crocodylomorph taxa have been described from the Late Jurassic of Portugal, mainly from the Guimarota Mine, located near the town of Leiria (Krebs & Schwarz, 2000). ...
Crocodylomorphs were a diverse clade in the Late Jurassic of Portugal, with six taxa reported to date. Here we describe 126 isolated teeth recovered by screen-washing of sediments from Valmitão (Lourinhã, Portugal, late Kimmeridgian–Tithonian), a vertebrate microfossil assemblage in which at least five distinct crocodylomorph taxa are represented. Ten morphotypes are described and attributed to five clades (Lusitanisuchus, Atoposauridae, Goniopholididae, Bernissartiidae and an undetermined mesoeucrocodylian). Four different ecomorphotypes are here proposed according to ecological niches and feeding behaviours: these correspond to a diet based on arthropods and small vertebrates (Lusitanisuchus and Atoposauridae), a generalist diet (Goniopholididae), a durophagous diet (Bernissartiidae) and a carnivorous diet. Lusitanisuchus mitracostatus material from Guimarota is here redescribed to achieve a better illustration and comparison with the new material.
This assemblage shares similar ecomorphotypes with other Mesozoic west-central European localities, where a diversity of crocodylomorphs lived together, avoiding direct ecological competition through niche partitioning. The absence of large marine crocodylomorphs, present in other contemporaneous assemblages, is here interpreted as evidence that the Valmitão assemblage was deposited in a freshwater environment, although sample bias cannot be completely ruled out. These affinities are further supported by the presence of lanceolate and leaf-shaped teeth associated with continental clades.
... aos morfotipos Tyrannosauridae e Troodontidae. É também de destacar a descoberta nesta jazida de vários dentes relacionados ao género de aves primitivas Archaeopteryx e ainda alguns dentes isolados e um fragmento de um dentário semelhantes aos descritos para o género do Cretácico Superior Paronychodon (Weigert, 1995;Zinke, 1998;Rauhut, 2000). ...
Ortega, F.; Malafaia, E.; Escaso, F.; Pérez García, A.; Dantas, P. (2009) Faunas de répteis do Jurássico Superior de Portugal. In: Pérez García, A., Silva, B. C., Malafaia, E. e Escaso, F. (eds). Paleolusitana 1: 43-56.
... The Upper Jurassic of Portugal yields abundant vertebrate remains, notably vertebrate microfossils as illustrated by the Guimarota Mine assemblage (Martin & Krebs, 2000). One of the more diverse clades is the archosaurs, with more than 30 species of dinosaurs described to date (Rauhut, 2000;Antunes & Mateus, 2003;Mateus et al., 2009;Escaso et al., 2014;Hendrickx & Mateus, 2014;Tschopp et al., 2015;Malafaia et al., 2018;Mocho et al., 2019). Other archosaurs are less well-studied and, to date, only six crocodylomorph taxa have been described from the Late Jurassic of Portugal, mainly from the Guimarota Mine, located near the town of Leiria (Krebs & Schwarz, 2000). ...
Crocodylomorphs were a diverse clade in the Late Jurassic of Portugal, with six taxa reported to date. Here we describe 126 isolated teeth recovered by screen-washing of sediments from Valmitão (Lourinhã, Portugal, late Kimmeridgian–Tithonian), a vertebrate microfossil assemblage in which at least five distinct crocodylomorph taxa are represented. Ten morphotypes are described and attributed to five clades (Lusitanisuchus, Atoposauridae, Goniopholididae, Bernissartiidae and an undetermined mesoeucrocodylian). Four different ecomorphotypes are here proposed according to ecological niches and feeding behaviours: these correspond to a diet based on arthropods and small vertebrates (Lusitanisuchus and Atoposauridae), a generalist diet (Goniopholididae), a durophagous diet (Bernissartiidae) and a carnivorous diet. Lusitanisuchus mitracostatus material from Guimarota is here redescribed to achieve a better illustration and comparison with the new material.
This assemblage shares similar ecomorphotypes with other Mesozoic west-central European localities, where a diversity of crocodylomorphs lived together, avoiding direct ecological competition through niche partitioning. The absence of large marine crocodylomorphs, present in other contemporaneous assemblages, is here interpreted as evidence that the Valmitão assemblage was deposited in a freshwater environment, although sample bias cannot be completely ruled out. These affinities are further supported by the presence of lanceolate and leaf-shaped teeth associated with continental clades.
... The Titanosauriformes was a widespread group of sauropods that probably appeared at the end of the Middle Jurassic (D'Emic, 2012) and extended across Europe, Gondwana and North America in the Late Jurassic (Fig. 7), although it seems that they did not reach Asia until the Early Cretaceous (Wilson and Upchurch, 2009;D'Emic, 2012) Galvesaurus in Brachiosauridae (Fig. 7) sheds new light on the abundance of this group and of titanosauriform sauropods in Iberia during the Late Jurassic. Titanosauriformes is represented during the Tithonian by the brachiosaurids Galvesaurus and Lusotitan, and there are also several teeth (Rauhut, 2000 and a femur that could be assigned to Titanosauriformes. This femur could correspond to one of the two already-defined taxa, or belong to a new one, M. Pérez-Pueyo, et al., 2019. ...
Galvesaurus herreroi is a sauropod from the Villar del Arzobispo Formation (late Kimmeridgian-early Tithonian), from the municipality of Galve (Teruel). Its phylogenetic relations have been long debated, so we carried out a phylogenetic analysis, using a new data matrix recently published by Carballido et al. (2017). The characters of Galvesaurus were coded on the basis of the redescription of the published remains and the description of two unpublished fossils: a right coracoid and a fragment of the right pubis. The results of the
analysis suggest the inclusion of Galvesaurus in the clade Titanosauriformes, as a sister taxon to Lusotitan, these two taxa form part of the Brachiosauridae clade. Likewise, a stratigraphic study was undertaken, placing the Galvesaurus site in the lower part of the Villar del Arzobispo Formation, thus assigning the sauropod a late Kimmeridgian-early Tithonian age.
لقد قمت شخصياً بدراسة موقع طبعات أقدام الديناصورات في قرية بيت زيت الفلسطينية المُحتلة لأول مرة في ربيع العام 1994 وكانت آخر دراسة لي في صيف العام 2013 . وقد قمت بنشر العديد من الأبحاث المتعلقة بديناصورات القدس الشريف في عدة مجلات ومواقع علمية .
وقد كانت طبيعة الدراسة التي أجريتها على ديناصورات القدس الشريف تتلخص بدراسة الأشكال المختلفة لطبعات الأقدام ، وأخذ قياساتها ، وأطوالها ، والتباعد بينها ، وإتجاهاتها ، والمقارنة بينها وبين طبعات أقدام أخرى متشابهة في دول أخرى مثل مصر وتونس والجزائر والمغرب . ومن ثم إستنتاج نوعية الديناصور، وحجمهُ ، وعُمرهُ ، وطريقة المشي ، ونوعية الغذاء المُحتمل ، والعلاقات الإجتماعية بين الأفراد .
Khalaf-Sakerfalke von Jaffa, Prof. Dr. Sc. Norman Ali Bassam Ali Taher (2015). Dinasurat Al-Quds Al-Shareef, Filasteen Al-Muhtala / Dinosaurs of Al-Quds (Jerusalem), Occupied Palestine. Gazelle: The Palestinian Biological Bulletin. ISSN 0178 – 6288. Volume 33, Number 122, February 2015. pp. 1-11. Dubai and Sharjah, United Arab Emirates (in Arabic). http://palestine-dinosaur.webs.com/dinosaur-al-quds-palestine
Ein Dentale-Fragment und Z a n e von theropoden Dinosauriern aus dem Oberen Jura der Kohlengrube Guimarota (Leiria, Portugal) werden beschrieben. Die Zahne 2hneln denen von Parorzychodorz im Vorhandensein von longitudinalen Gruben auf der Zahnkrone, unterscheiden sich jedoch durch den Besitz von Serrationen. Drei Zahne dieses Typus befinden sich noch in dem Dentale-Fragment. Zusatzlich werden Theropoden-Zane mit den gleichen Charakteristika aus der Unteren Kreide von Galve (Teruel, Spanien) beschrieben. Die Bedeutung dieser Fossilien fiir die Bewertung des Auftretens longitudinaler Gruben auf den Z a n e n von Theropoden sowie fiir die systematische Stellung von Paronychodon wird diskutiert. Abstrack Teeth and a fragmentary dentary of small theropod dinosaurs from the Upper Jurassic lignite coal mine of Guimarota (Leiria, Portugal) are described. The teeth are similar to Paronychodon in showing longitudinal grooves on the crown, but differ in having serrated edges. Three of those teeth can still be found in the dentary fragment. Also, theropod teeth from the Lower Cretaceous of Galve (Teruel, Spain), which show the same characteristics are described. The significance of these specimen for the judgement of the appearance of longitudinal grooves on theropod teeth as well as for the systematic position of Paronychodon are discussed.
The question of the origin of birds can be equated with the origin of Archaeopteryx, the oldest known bird. Analysis of the five presently known skeletal specimens of Archaeopteryx, and comparison with the skeletal anatomy of the several reptilian groups that have been proposed as possible ancestors of birds (Ornithopoda, Theropoda, Pseudosuchia and Sphenosuchidae), confirm the conclusions (long rejected by most subsequent workers) of Heilmann (1926), Lowe (1935, 1944) and Holmgren (1955), namely, that the skeletal anatomy of Archaeopteryx is extraordinarily similar to that of contemporaneous and succeeding coelurosaurian dinosaurs. Rejection of these similarities as adaptive structures only (parallel or convergent similarities), and therefore of no phylogenetic importance, is here considered invalid. Heilmann was the first to identify the only evidence that has been cited so far for dismissing coelurosaurian-avian ancestral-descendant relationships, the supposed absence of clavicles in all theropods, and on that basis suggested a common Archaeopteryx-dinosaur ancestry among pseudosuchian reptiles. That evidence is negative and thus inconclusive, and is now known to be false. With the exception of fused clavicles and unique ischial morphology, virtually every skeletal feature of Archaeopteryx is known in several contemporaneous or near-contemporary coelurosaurian dinosaurs and many of these conditions are unrelated, specialized features (the detailed morphology of the manus, metacarpus, carpus, humerus, scapulocoracoid, pes, metatarsus, tarsus, femur, pubis, ilium, skull and mandibles). The presence of so many derived characters in common clearly establishes that the closest ancestral affinities of Archaeopteryx are with coelurosaurian theropods. There is no contrary evidence and any other explanation is illogical. Ornithopod-Archaeopteryx ancestral-descendant affinities may be dismissed because of the false "avian" organization of the pelvis in the Berlin specimen of Archaeopteryx and the merely superficially bird-like construction of the ornithischian pelvis. The suite of specialized characters unique to ornithischians (e.g., predentary, tooth morphology), that occur even in Triassic representatives, is further evidence for dismissing close affinity between ornithopods and Archaeopteryx. The supposed close relationship between birds and pseudosuchians is judged to be remote at best, due to the completely primitive nature of the few anatomical features which pseudosuchians have in common with Archaeopteryx. Sphenosuchus, a primitive and early archosaur, is also a potential avian ancestor, but existing evidence consists of primitive archosaurian features plus a few similarities with certain modern birds. These similarities, which are present in two groups that are separated from each other by more than 200 million years, and which cannot be demonstrated in Archaeopteryx, are considered irrelevant to the origins of Archaeopteryx and subsequent birds. All available evidence indicates unequivocally that Archaeopteryx evolved from a small coelurosaurian dinosaur and that modern birds are surviving dinosaurian descendants. Stated simply, avian phylogeny was: Pseudosuchia → Coelurosauria → Archaeopteryx → higher birds.
A basicranium from the Cleveland-Lloyd Dinosaur Quarry is the most advanced of any Jurassic theropod, combining features considered synapomorphies for two different Cretaceous theropod families, the Itemiridae and Tyrannosauridae. The basicranium has large pockets on the basipterygoid processes, flat basal tubera, and is extremely shortened, so that the basisphenoidal sinus is visible only in occipital view and the basiptyerygoid processes are positioned at the posterolateral corners of the braincase. CT scanning reveals the basicranium to be extensively pneumatized.A number of lines of evidence suggests that this specimen is referable to the rare Morrison theropod Stokesosaurus clevelandi. Stokesosaurus may be the earliest itemirid, the earliest tyrannosaurid, or a lineage that independently reached a comparable level of basicranial organization. Unfortunately the limited amount of known Stokesosaurus material does not allow for choosing among these alternatives. However, it is clear that Morrison theropods are morphologically much more diverse than suspected.
The discovery of a nearly complete skeleton of Tenontosaurus tilletti and closely associated multiple shed teeth of the dromaeosaur Deinonychus antirrhopus provides evidence that may support the often repeated suggestion that Deinonychus was a pack-hunting predator. The taphonomy of the specimen adds weight to the additional conclusion that Tenontosaurus was the specific food preference of the Deinonychus predator population. Among theropods, the only other specific animals that have been found as unmistakable food objects are Bavarisaurus in Compsognathus and Coelophysis in Coelophysis. These two could have been examples of opportunistic incidental predation or scavenging, but it appears that Deinonychus actively preyed on a deliberate food choice, Tenontosaurus.
This paper rectifies several widespread misunderstandings: about the anatomy and taxonomic status of the primitive ornithischian dinosaur Fabrosaurus australisGinsburg, 1964. The type specimen of this dinosaur is considered to be diagnostic on account of its highly characteristic dental morphology. Fabrosaurus australis lacks special foramina in the medial wall of the dentary and is, therefore, indistinguishable from Lesothosaurus diagnosticusGalton, 1978 — which is regarded as a junior synonym. The ischium of Fabrosaurus possesses an obturator process, which is commonly regarded as a synapomorphy defining the ornithischian suborder Ornithopoda. All fabrosaurid remains so far described from the Lower Jurassic of southern Africa are referable to the genus Fabrosaurus, and probably to the single species F. australis. There is no reason to assume that ornithischian tooth morphology is worthless for taxonomic purposes.RésuméCe travail rectifie quelques malentendus répandus au sujet de l'anatomie et de la position taxonomique du dinosaure ornithischien primitif Fabrosaurus australisGinsburg, 1964. Le spécimen type est considéré comme diagnostique en raison de sa morphologie dentaire très caractéristique. Fabrosaurus australis ne possède pas les foramina spéciaux à la surface médiale du dentaire et, pour cette raison, est indifférenciable de Lesothosaurus diagnosticusGalton, 1978 — manifestement un synonyme ultérieur. L'ischion de Fabrosaurus australis posséde un processus obturateur, ordinairement admis comme caractère spécialisé du sous-ordre Ornithopoda parmi les ornithischiens. Tous les restes de fabrosauridés décrit à ce jour du Jurassique inférieur d'Afrique du Sud concernent le genre Fabrosaurus, et probablement la seule espèce F. australis. Il n'y a aucune raison de supposer que la morphologie dentaire des ornithischicus est sans valeur à des fins taxonomiques.
Phylogenetic studies and new fossil evidence have yielded fundamental insights into the pattern and timing of dinosaur evolution and the emergence of functionally modern birds. The dinosaurian radiation began in the Middle Triassic and significantly predates their rise to global dominance by the end of the period. The phylogenetic history of ornithischian and saurichian dinosaurs reveals evolutionary trends such as increasing body size. Adaptations to herbivory dinosaurs were not tightly correlated with marked floral changes. Dinosaurian biogeography during the era of continental breakup principally involved dispersal and regional extinction.
Two spectacular fossilized dinosaur skeletons were recently discovered in Liaoning in northeastern China. Here we describe the two nearly complete skeletons of a small theropod that represent a species closely related to Compsognathus. Sinosauropteryx has the longest tail of any known theropod, and a three-fingered hand dominated by the first finger, which is longer and thicker than either of the bones of the forearm. Both specimens have interesting integumentary structures that could provide information about the origin of feathers. The larger individual also has stomach contents, and a pair of eggs in the abdomen.