Publications in the Year: 2008

Book Chapter

Mateus, O.  2008.  Fósseis de transição, elos perdidos, fósseis vivos e espécies estáveis. Evolução: História e Argumentos. (Levy, et al, Eds.).:77-96., Lisboa: Esfera do Caosmateus_2008_evolucao_fosseis_de_transicao.pdf
Mateus, O, Jacinto J.  2008.  Hemidactylus turcicus. Atlas dos Anfíbios e Répteis de Portugal. :130-131., Lisboa: A. Loureiro, N. Ferrand de Almeida, M.A. Carretero, O.S. Paulo. Instituto da Conservação da Natureza e da Biodiversidademateus__jacinto_2008_hemidactylus_turcicus_in_atlas_dos_anfibios_e_repteis_de_portugal.pdf

Conference Paper

Mateus, O, Dyke G, Motchurova-Dekova N, Ivanov P, Kamenov GD.  2008.  The Bulgarian dinosaur: did it exist? European late Cretaceous ornithomimosaurs 56th Symposium of Vertebrate Palaeontology and Comparative Anatomy. :47., Dublin Abstract

For historical and geological reasons the dinosaurian fossil record from central Europe is little known. Here we describe and interpret a portion of a left humerus from the Upper Maastrichtian of Vratsa district in north-western Bulgaria. This bone is the first known record of a dinosaur from Bulgaria; it is certainly a theropod, probably an ornithomimosaur. We discuss the fossil record of other similar fossils of theropod dinosaurs, in particular other problematic remains from the Maastrichtian of Belgium. Rare Earth Element (REE) analysis combined with strontium (Sr) isotope data demonstrate that the Bulgarian dinosaur was initially fossilised in a terrestrial environment and then later re-worked into Late Maastrichtian marine sediments.

Mateus, O, Jacobs LL, Polcyn MJ, Schulp AS, Neto AB, Antunes MT.  2008.  Dinosaur and turtles from the Turonian of Iembe, Angola. Livro de Resumos de Tercer Congreso Latinoamericano de Paleontologia de Vertebrados. :156., Neuquén, Argentina Abstractmateus_et_al_2008_dinosaur_and_turtles_from_the_turonian_of_iembe_angola.pdf


Mateus, O, Milan J.  2008.  Sauropod forelimb flexibility deduced from deep manus tracks. 52th Paleontological Association Annual Meeting. 18th-21st December 2008,. :67-68.: University of Glasgow Abstractmateus__milan_2008_palass_sauropod_forelimb_flexibility_deduced_from_deep_manus_tracks.pdf

Sauropods are often considered to have very limited mobility and reduced limb flexibility, mainly due to their giant size and consequent weight. In the Upper Jurassic Lourinhã Formation, central-west Portugal, deep vertical natural casts of sauropod manus tracks are often preserved as the infills of the original tracks. These manus tracks are vertical-walled, with marks of the striations of the skin scales, showing that the movement of the sauropod manus impacting and exiting the mud was totally vertical with no horizontal component of the stride. Some tracks are up to 66 cm deep, which is equivalent to the height of whole sauropod manus. This means that sauropods could lift their anterior feet in a complete vertical manner. Such movement is only possible if there is mobility at elbow and shoulder articulations in a higher degree than previously thought for sauropods. Our vision of sauropod limbs as inflexible columns has to be updated to a more dynamic model for limbs and body.

Mateus, O, Maidment SCR, Christiansen NA.  2008.  A new specimen aff. Dacentrurus armatus (Dinosauria: Stegosauridae) from the Late Jurassic of Portugal. Livro de Resumos de Tercer Congreso Latinoamericano de Paleontologia de Vertebrados. :157., Neuquén, Argentina Abstractmateus_et_al_2008_a_new_specimen_aff._dacentrurus_armatus_dinosauria_stegosauridae_from_the_late_jurassic_of_portugal.pdf


Schulp, AS, Polcyn MJ, Mateus O, Jacobs LL, Morais ML.  2008.  A new species of Prognathodon (Squamata, Mosasauridae) from the Maastrichtian of Angola, and the affinities of the mosasaur genus Liodon. Proceedings of the Second Mosasaur Meeting, Fort Hays Studies Special Issue 3, Fort Hays State University, Hays, Kansas. :1-12. Abstractschulp_et_al_2008_prognathodon_kianda.pdf

Here we describe a new species of the mosasaurine genus Prognathodon from the Maastrichtian of Namibe, Angola, on the basis of five specimens which represent most of the cranial skeleton including the diagnostic quadrate. Phylogenetic analysis shows this new taxon, P. kianda nov. sp., to be the sister taxon to all other species of Prognathodon. It is unique amongst Prognathodon in possessing a high marginal tooth count and relatively small pterygoid teeth. The tooth morphology in the new taxon is reminiscent of some species of the genus Liodon, allowing association of Liodon-like dentition with otherwise Prognathodon-like crania, and thus resolves the long-standing question of the phylogenetic affinities of Liodon.

Araujo, R, Castanhinha R, Mateus O.  2008.  Major trends in the evolution of teeth and mandibles in ornithopod dinosaurs. Livro de Resumos de Tercer Congreso Latinoamericano de Paleontología de Vertebrados. :18., Neuquén, Argentina Abstractaraujo_et_al._2008._major_trends_in_the_evolution_of_teeth_and_mandibles_in_ornithopod_dinosaurs.pdf


Castanhinha, R, Araujo R, Mateus O.  2008.  Reptile Egg Sites From Lourinhã Formation, Late Jurassic, Portugal. Livro de Resumos de Tercer Congreso Latinoamericano de Paleontologia de Vertebrados. , Neuquén, Argentina Abstractcastanhinha_et_al_2008_reptile_egg_sites_from_lourinha_formation_late_jurassic_portugal.pdf


Mateus, O, Natário C, Araújo R, Castanhinha R.  2008.  A new specimen of spinosaurid dinosaur aff. Baryonyx from the Early Cretaceous of Portugal, Jan. Livro de Resumos do X Congresso Luso-Espanhol de Herpetologia. :51. Abstract


Mateus, O, Antunes MT.  2008.  Landmarks in the history of dinosaur paleontology in Portugal, focusing on skeletal remains. Abstract volume, Dinosaurs - A Historical Perspective, 6-7 may 2008. , London Abstract

Portugal has been providing dinosaur remains since, at least, 1863. The 18th century tiles depicting the legend of Our Lady in Cabo Espichel are probably the oldest known dinosaur track illustration. To our knowledge, the first remains found in Portugal were theropod teeth collected near Porto das Barcas (Late Jurassic of Lourinhã) in June 20th, 1863 by the geologist Carlos Ribeiro (1813-1882). The first dinosaur paper was written by Henri Sauvage (1842-1917) published in 1896. All remains collected since 19th century were gathered in a work signed by Albert de Lapparent (1905-1975) and Georges Zbyszewski (1909-1999 ) titled Les Dinosauriens du Portugal (1957) that was a significant milestone in the Portuguese dinosaur paleontology and gives the state-of-the-art by the time. Several dinosaurs are named, described, depicted and mapped in that monograph. The first track record is given by Jacinto Pedro Gomes (1844-1916) in 1916. Concerning the non-scientific literature referring to dinosaurs, in 1884 the newspaper Occidente reports the Bernissart findings in Belgium. In the 1959 occurs the first visit to Portugal of Walter Kühne (1911-1991) from the Free University of Berlin. Further visits and work granted the access to the Guimarota Mine and other Late Jurassic deposits in the 1960’s, 70’s and 80’s with a high number of publications. In the 1980’s and early 1990’s starts a progressive era for dinosaur paleontology in Portugal with the works of Peter Galton, Miguel Telles Antunes, the Natural History Museum, the Museum of Lourinhã and the New University of Lisbon, Oliver Rauhut, and others.

Mateus, O.  2008.  Checklist for Late Jurassic reptiles and amphibians from Portugal. Livro de Resumos do X Congresso Luso-Espanhol de Herpetologia. :55., Coimbra Abstractmateus_2008_lista_de_repteis_e_anfibios_do_jurassico_superior_de_portugal__list_congressoherpetolog.pdf

The richness of Late Jurassic vertebrates in Portugal is known since the 19th century by Paul Choffat, Henri Sauvage and other. The Kimmeridgian Guimarota fauna assemblage is the best known, followed by the fauna of Lourinhã formation. Here is presented an attempt to provide a checklist of the reptiles and amphibians of the Late Jurassic. Amphibia: Lissamphibia (Celtedens, cf. Marmorerpeton, Discoglossidae indet.). Chelonia: Eucryptodira (Pleurosternidae indet., Platychelyidae indet., Plesiochelys cf. etalloni, Plesiochelys choffati, Anosteirinae indet.). Squamata: Scincomorpha (Becklesius hoffstetteri; Paramacellodus sp., Saurillodon proraformis, S. henkeli, S. cf. obtusus). Squamata: Anguimorpha (Dorsetisaurus pollicidens, Parviraptor estesi). Crown Lepidosauromorpha (Marmoretta sp.). Choristodera: Cteniogenidae (Ctenogenys reedi). Sauropterygia: Plesiosauria: Cryptoclidoidea: Cryptoclididae indet. Crocodylomorpha (Lisboasaurus estesi, L. mitrocostatus). Crocodyliformes: Neosuchia (Machimosaurus hugii, Goniopholis cf. simus, Goniopholis baryglyphaeus, cf. Bernissartia, Atoposauridae, Theriosuchus guimarotae, cf. Alligatorium, Metriorhynchus sp.). Pterosauria (Rhamphorhynchus sp., Pterodactylus sp.). Dinosauria: Theropoda (Ceratosaurus sp. , Torvosaurus sp., Lourinhanosaurus antunesi, Allosaurus europaeus, Cf. Compsognathus sp., cf. Richardoestesia sp., Dromaeosaurinae indeter., Velociraptorinae indeter., cf. Archaeopteryx sp., aff. Paronychodon). Dinosauria: Sauropoda: Eusauropoda (Dinheirosaurus lourinhanensis, Lourinhasaurus alenquerensis, Lusotitan atalaiensis, Apatosaurus sp.). Dinosauria: Ornithischia: Thyreophora (Dacentrurus armatus, Stegosaurus sp., Dracopelta zbyszewskii). Dinosauria: Ornithischia: Ornithopoda (Phyllodon henkeli, Dryosaurus sp., Hypsilophodon sp., Alocodon kuehnei, Trimucrodon cuneatus, Draconyx loureiroi).

Journal Article

Mateus, O.  2008.  Two ornithischian dinosaurs renamed: Microceratops Bohlin 1953 and Diceratops Lull 1905. Journal of Paleontology. 82:423., Number 2 Abstractmateus_2008_two_ornithischians_renamed__microceratops_bohlin_1953_and_diceratops_lull_.pdfWebsite

dinosaur genera Diceratops Lull, 1905 and Microceratops Bohlin, 1953 are preoccupied by the Hymenoptera insects, Diceratops Foerster, 1868 and Microceratops Seyrig, 1952, respectively. Therefore, the name of the ceratopsian dinosaur Diceratops Lull, 1905 from the Late Cretaceous of United States is a junior homonym of the hymenoptera Diceratops Foerster, 1868. Diceratus n. gen. (Greek di ‘‘two,’’ Greek ceratos ‘‘horned’’) is proposed as the replacement name of Diceratops Lull, 1905. Some workers have considered Diceratops synonymous with Triceratops (e.g., Dodson and Currie, 1990) but it was reinstated by Forster (1996) after analysis of the characteristics of all existing ceratopsid skulls, and recent reviews (e.g., Dodson et al., 2004) have considered Diceratops a valid genus.
Due to preoccupation, the name of the ceratopsian dinosaur Microceratops Bohlin, 1953 from the Cretaceous of the Gobi is
a junior homonym of the insect Microceratops Seyrig, 1952. Microceratus n. gen. (Greek micro ‘‘small,’’ Greek ceratos ‘‘horned’’) is proposed as the replacing name of Microceratops Bohlin, 1953.
Sereno (2000:489) has declared Microceratops a nomen dubium since the holotype material lacks any diagnostic features, a
convention followed by You and Dodson (2004:480). However, the name is still used by Le Loeuff et al. (2002), Lucas (2006),
Alifanov (2003) and Xu et al. (2002), and such practice justifies the renaming of the genus.
In order to preserve some stability, the names chosen here deliberately preserve the same prefixes.

Mateus, O, Milan J.  2008.  Ichnological evidence for giant ornithopod dinosaurs in the Upper Jurassic Lourinhã Formation, Portugal. Oryctos. 8:47-52. Abstractmateus_and_milan_2008_ichnological_evidence_for_giant_ornithopod_big_ornithopod_track_from_u_j_lourinha_fm_portugal.pdfWebsite

The Upper Jurassic Lourinhã Formation (Lusitanian Basin, Portugal) contains a diverse dinosaur fauna comprising theropods, sauropods, stegosaurs, ankylosaurs and several genera of ornithopods. The sedimentology in the area favours preservation of tracksways, and tracks from most of the dinosaurs are also represented by skeletal remains. During fieldwork in the summer of 2003 a new, large, tridactyl track was found at the beach of Vale Frades, approximately 6 km north of Lourinhã (central west Portugal). The track was found together with a stegosaur track on a clay bed exposed within the intertidal zone. Due to the immediate danger of erosion, the track was collected and is now on display at Museu da Lourinhã. The track is 70 cm long and 69 cm wide, the toes are short and broad, with indications of short blunt claws, and there is a high angle of divarication between the outer digits. The shape and dimensions of the track identifies it as deriving from an ornithopod dinosaur with an estimated hip height around three metres. Although very large ornithopods are known from the Cretaceous, the largest known Jurassic ornithopod is Camptosaurus from North America, and the largest known from Portugal is the camptosaurid Draconyx loureiroi. Neither of these reached the body size suggested by the new track. So far the track described herein is the only evidence for a Jurassic ornithopod of that size.

Rita, F, Mateus O, Overbeeke M.  2008.  Tomografia Computorizada na Deteccão de Fraudes em Fósseis. Acta Radiológica Portuguesa. 80:83-84., Number 20 Abstractrita_et_al_2008_tomografia_computorizada_na_deteccao_de_fraudes_em_fosseis.pdfWebsite

The material in analysis is the skull of an Ornitiquous Psittacosaurus of the China Cretaceous suspicious of being a fraud. The fossil described here appeared to be in very good condition and conservation. The skull is almost complete but because it is filled by sediment, this prevents an analyse of the intra-skull anatomy.
With the intuition of confirming or not the existence of fossiled bone elements in the interior of the sedimented mass that filled the Psittacossaurus skull, it was submitted to a Computorized Tomography.
The Psittacosaurus skull showed an unexpected absorption of the x-rays, because of the outstanding differences of density between the bone and the matrix due to the fact that the interior of the skull was composed by an amalgam of materials, where a less compact and relatively homogeneous material (soil and wax) was found and that material united and mounted the whole skull and the normal bone structures were non-existing.
The capacity of the Computorized Axial Tomography of differentiating materials with different densities of absorption of x-rays, permitted an easy and reliable investigation and explained beyond doubt the quality of the fossil specimen studied, concluding with no doubt that in spite of the realistic aspect, we had come before a fraud.

Mateus, O, Overbeeke M, Rita F.  2008.  Dinosaur Frauds, Hoaxes and "Frankensteins": How to distinguish fake and genuine vertebrate fossils. Journal of Paleontological Techniques. 2:1-5.. Abstractmateus_et_al_2008_dinosaur_frauds_hoaxes_and_frankensteins-_how_to_distinguish_fake_and_genuine_vertebrate_fossils._journal_of_paleontological_techniques.pdfWebsite

Dinosaurs and other fossils have been artificially enhanced, or totally forged, to increase their commercial value. The most problematic forgeries to detect are based on original fossils that are artificially assembled. Several techniques are suggested for detecting hoaxes: detailed visual examination, chemical analysis, Xray or CT-scan, and ultraviolet light. It is recommended that museums and paleontological researchers do not purchase and/or trade fossils lacking clear provenience information. Exceptions to that general rule should be closely examined using techniques described herein.

Mateus, O, Araújo R.  2008.  Stone-splitters and expansive demolition agents: breaking big rocks with little effort on vertebrate paleontological excavations. Journal of Paleontological Techniques. 3:1-6. Abstractmateus__araujo_2008_stone-splitters_and_expansive_demolition_agents_jpt_n003_oct.pdfWebsite

Two techniques (stone-splitters and demolition agents) are revealed to be efficient methods for breaking large stone blocks in extreme paleontological excavation. In certain conditions – where security factors, permission issues, terrain conditions, rock properties are problematic – the traditional methods for breaking large rock blocks cannot be applied (e.g. crane trucks or explosives). Using an expansive demolition agent or stone-splitters after drilling equidistant holes not only allows a cheap, quick and safe solution but also permits precise removal of up to 9 ton blocks. Stone-splitters are a three-part tool that when inserted linearly and equidistantly along a brittle rock mass cause a precise fracture.

Hayashi, S, Carpenter K, Watabe M, Mateus O, Barsbold R.  2008.  Defensive weapons of thyreophoran dinosaurs: histological comparisons and structural differences in spikes and clubs of ankylosaurs and stegosaurs. Journal of Vertebrate Paleontology. 28(3, Supplement):89A-90A., Number Suppl. to 3 Abstracthayashi_et_al_2008_histology_stegosaurs_defensive_weapons_of_thyreophoran_dinosaurs-_histological_comparisons_and_structural_differences_in_spikes_and_clubs_of_ankylosaurs_and_stegosaurs.pdfWebsite

Thyreophoran dinosaurs have spike- and club-shaped osteoderms probably used for defensive weapons. The structural and histological variations have been little known. Here, we provide the comparisons of the internal structures in defensive weapons of ankylosaurs and stegosaurs, using spikes of a polacanthid (Gastonia) and a nodosaurid (Edmontonia), clubs of ankylosaurids (Saichania and Ankylosauridae indet. from Canada), and spikes of stegosaurids (Stegosaurus and Dacentrurus), which sheds light on understandings of evolutionary history and functional implications of defensive weapons in thyreophorans. In ankylosaurs, the structural and histological features of spikes and clubs are similar with those of small osteoderms in having thin compact bones, thick cancellous bones with large vascular canals, and abundant collagen fibers. A previous study demonstrated that each of three groups of ankylosaurs (polacanthid, nodosaurid, and ankylosaurid) has distinct characteristic arrangements of collagen fibers in small osteoderms. This study shows that spikes and clubs of ankylosaurs maintain the same characteristic features for each group despite of the differences in shapes and sizes. Conversely, the spike-shaped osteoderms in primitive (Dacentrurus) and derived (Stegosaurus) stegosaurids have similar structure to each other and are significantly different from the other types of stegosaur osteoderms (throat bony ossicles and plates) in having thick compact bones with a medullary cavity. These lack abundant collagen fibers unlike ankylosaur osteoderms. The spikes of ankylosaurs and stegosaurs are similar in shape, but their structural and histological features are different in having unique structures of collagen fibers for ankylosaurs and thick compact bones for stegosaurs, providing enough strength to have large spikes and to use them as defensive weapons. Although the shapes of ankylosaur clubs are different from spikes, the internal structures are similar, suggesting that ankylosaurs maintain similar structures despite of different shapes in osteoderms. These results indicate that ankylosaurs and stegosaurs used different strategies independently to evolve defensive weapons.