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Mateus, O. (2009).  The sauropod Turiasaurus riodevensis in the the Late Jurassic of Portugal. Journal of Vertebrate Paleontology. 29, 144., Number 3 Abstract
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Mateus, O., Jacobs L. L., Polcyn M. J., Schulp A. S., Neto A. B., & Antunes M. T. (2008).  Dinosaur and turtles from the Turonian of Iembe, Angola. Livro de Resumos de Tercer Congreso Latinoamericano de Paleontología de Vertebrados. 156–156., Neuquén, Argentina Abstract
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Mateus, O. (2013).  Cabinda revisited: age and environment of new Cenozoic vertebrate fossils from northern Angola. 45, , 1 Abstract

In the early 20thcentury, Belgian naturalists reported Paleocene and Eocene sharks, the bothremydid pleurodiran turtleTaphosphrys(formerlyBantuchelys), and a neosuchian and the dyrosaurid crocodyliformCongosaurusfrom coastal outcrops near Landana in the northern province of Cabinda, Angola. In 1935, rare and fragmentary mammals were reported from strata at Malembo Point, south of Landana, and originally considered to be Miocene in age. Subsequent re-identification of the mammal fossils suggested that the Malembo deposits are Lower Oligocene based on the presence of an arsinoithere and hyracoids. An anthropoid canine, originally identified as a carnivore incisor, was also recognized. In four recent expeditions to Cabinda, Projecto PaleoAngola has traced and measured the stratigraphy between Landana and Malembo Point and sampled these deposits for pollen, stable isotopes, detrital zircons, paleomagnetic stratigraphy, and for U/Pb dating of bones, teeth, and coprolites. Although the faunas from all Cabinda localities are dominated by sharks and rays, new discoveries from Landana include a complete cheloniid cryptodire turtle skull, a small snake vertebra, and a bird bone. Discoveries from the Malembo level include a narrow-snouted crocodyliform similar toCongosaurusandEuthecodon, an arsinoithere anterior tooth, an upper molar similar to that of the ptolemaiidanKelba, an unidentified mammalian incisor, and a large primate-like premolar. Recent biostratigraphic advances in East Africa and the new fossil discoveries in Cabinda suggest similarity to late Oligocene faunas in Ethiopia and Kenya, although the large primate-like premolar is unique. To this day, the fossil localities of Malembo provide the only coastal, low latitude, low elevation record of West African Cenozoic terrestrial mammals. https://gsa.confex.com/gsa/2013AM/webprogram/Paper232115.html

Mateus, O., Jacobs L. L., Polcyn {M. J. }, Myers T. S., & Schulp A. S. (2015).  The fossil record of testudines from Angola from the Turonian to Oligocene. : Journal of Vertebrate Paleontology Abstract
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Mateus, O., Milàn J., Romano M., & Whyte M. A. (2011).  New finds of stegosaur tracks from the Upper Jurassic Lourinhã formation, Portugal. Acta Palaeontologica Polonica. 56, 651-658., Number 3 Abstract
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Mateus, O., & Antunes M. T. (2001).  Draconyx loureiroi, a new camptosauridae (Dinosauria, Ornithopoda) from the Late Jurassic of Lourinhã, Portugal. Annales de Paléontologie. 87, 61–73., jan, Number 1: Elsevier {BV} AbstractWebsite
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Mateus, O. (2009).  New specimens of Angolasaurus bocagei and comments on the early radiations of plioplatecarpine mosasaurs. Journal of Vertebrate Paleontology. Journal of Vertebrate Paleontology. 29, 165A., 1, Number 3: Taylor & Francis Abstract

NEW SPECIMENS OF ANGOLASAURUS BOCAGEI AND COMMENTS ON THE EARLY RADIATIONS OF PLIOPLATECARPINE MOSASAURS POLCYN, Michael, SMU, Dallas, TX, USA; JACOBS, Louis, SMU, Dallas, TX, USA; MATEUS, Octávio, Museu da Lourinhã, Lourinhã, Portugal; SCHULP, Anne, Natuurhistorisch Museum Maastricht, Maastricht, Netherlands New, well preserved material of the Turonian mosasaur Angolasaurus bocagei from the Tadi Beds of the Itombe Formation in northern Angola, allows detailed redescription of its morphology and reassessment of its phylogenetic relationships. Angolasaurus had been previously referred to the genus Platecarpus; however, phylogenetic analysis confirms the valid taxonomic status of A. bocagei, and reconstructs that taxon within a clade that also includes the genera Selmasaurus and Ectenosaurus. These forms are united by an elaborated infrastapedial process of the quadrate and a unique ridge-like descending process of the parietal forming the supraoccipital articulation, but also retain a relatively plesiomorphic configuration of the braincase. That clade is united with all other plioplatecarpines by a number of derived characters including the presence of a novel basicranial circulation pattern. In Africa, North and South America, early plioplatecarpines are known by the Middle Turonian and Angolasaurus and closely related forms appear by the Upper Turonian. Selmasaurus and Ectenosaurus are a rare faunal component of the Santonian and Campanian of North America. Platecarpus planifrons appears in the Coniacian of North America and represents the plesiomorphic condition of the clade containing the remaining species of Platecarpus and Plioplatecarpus, that appears in the Santonian and persist until the end of the Cretaceous, reaching global distribution. The temporal and geographic distribution of these radiations suggest influence of paleogeography and eustatic sea levels.

Mateus, O. (1999).  Monofilia dos dinossauros e Origem das Aves: Serão as aves dinossauros?. Actas do II Congresso de Ornitologia. 184–185., Lisboa Abstract
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Mateus, O., Jacobs L. L., Polcyn M. J., Schulp A. S., Neto A. B., & Antunes M. T. (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

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Mateus, O., & Azinheira C. (1996).  Passeriformes nidificantes da Ribeira da Viscossa (Évora). (Spea, Ed.).Livro de resumos do I Congresso de Ornitologia. Abstract
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Mateus, O., Polcyn M. J., Jacobs L. L., Araújo R., Schulp A. S., Marinheiro J., Pereira B., & Vineyard D. (2012).  Cretaceous amniotes from Angola: dinosaurs, pterosaurs, mosasaurs, plesiosaurs, and turtles. V Jornadas Internacionales sobre Paleontología de Dinosaurios y su Entorno. 71-105., Salas de los Infantes, Burgos Abstractmateus_et_al_2012_amniotes_from_angola_cretaceous_amniotes_from_angola_dinosaurs_pterosaurs_mosasaurs.pdf

Although rich in Cretaceous vertebrate fossils, prior to 2005 the amniote fossil record of Angola was poorly known. Two horizons and localities have yielded the majority of the vertebrate fossils collected thus far; the Turonian Itombe Formation of Iembe in Bengo Province and the Maastrichtian Mocuio Formation of Bentiaba in Namibe Province. Amniotes of the Mesozoic of Angola are currently restricted to the Cretaceous and include eucryptodire turtles, plesiosaurs, mosasaurs, pterosaurs, and dinosaurs. Recent collecting efforts have greatly expanded our knowledge of the amniote fauna of Angola and most of the taxa reported here were unknown prior to 2005.

Mateus, O. (2016).  Exemplos bizarros de evolucão em dinossauros e alguns casos portugueses. Do Big Bang ao Homem. 81–95.: U.Porto Edicões Abstract
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Mateus, O., Dyke G., Motchurova-Dekova N., Ivanov P., & Kamenov G. D. (2008).  The Bulgarian dinosaur: did it exist? European late Cretaceous ornithomimosaurs. 56th Symposium of Vertebrate Palaeontology and Comparative Anatomy. 47., Dublin Abstract
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Mateus, O., Natário C., Araújo R., & Castanhinha R. (2008).  A new specimen of spinosaurid dinosaur aff. Baryonyx from the Early Cretaceous of Portugal. Livro de Resumos do X Congresso Luso-Espanhol de Herpetologia. 51., Jan Abstract

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Mateus, O., Jacobs L., Polcyn M., Schulp A. S., Vineyard D., Neto A. B., & Antunes M. T. (2009).  The oldest African eucryptodiran turtle from the Cretaceous of Angola. Acta Palaeontologica Polonica. 54, 581-588., Jan: Univ Agostinho Neto, Univ Nova Lisboa, Museu Lourinha, Acad Ciencias Lisboa, Nat Hist Museum Maastricht, So Methodist Univ Abstractmateus_et_al_2009_the_oldest_african_angolachelys_angola_turtle.pdfWebsite

A new Late Cretaceous turtle, Angolachelys mbaxi gen. et sp. nov., from the Turonian (90 Mya) of Angola, represents the oldest eucryptodire from Africa. Phylogenetic analysis recovers Angolachelys mbaxi as the sister taxon of Sandownia harrisi from the Aptian of Isle of Wight, England. An unnamed turtle from the Albian Glen Rose Formation of Texas (USA) and the Kimmeridgian turtle Solnhofia parsonsi (Germany), are successively more distant sister taxa. Bootstrap analysis suggests those four taxa together form a previously unrecognized monophyletic clade of marine turtles, herein named Angolachelonia clade nov., supported by the following synapomorphies: mandibular articulation of quadrate aligned with or posterior to the occiput, and basisphenoid not visible or visibility greatly reduced in ventral view. Basal eucryptodires and angolachelonians originated in the northern hemisphere, thus Angolachelys represents one of the first marine amniote lineages to have invaded the South Atlantic after separation of Africa and South America.

Mateus, O. (2013).  Crocodylomorphs from the Mesozoic of Portugal and a new skull of eusuchian from the Late Cretaceous. 2013 Hwaseong International Dinosaurs Expedition Symposium, pp.66-67.. , Hwaseong, South Korea Abstractmateus_2013_crocodylomorphs_portugal_new_skull.pdf

The diversity of fossil crocodylomorphs in Portugal is high, with occurrence as old as Mystriosaurus (=Steneosaurus) bollensis from the Lower Jurassic. The Late Jurassic forms are the better documented, and include the following taxa: Machimosaurus hugii, Lisboasaurus estesi Seiffert, 1973, Lusitanisuchus mitrocostatus Seiffert, 1975; Schwarz & Fechner 2004, Theriosuchus guimarotae Schwarz and Salisbury 2005, Cf. Alligatorium, Goniopholis baryglyphaeus, and a crocodylomorph-like eggs in dinosaur nests (Mateus et al., 1998; Ricqlès et al., 2001). From the Lower Cretaceous were reported a few dinosaurs but its record is strangely scarce in crocodylomorphs (Mateus et al., 2011). The Upper Cretaceous crocodiles show a large diversity, but it is mostly based in fragmentary material that require revision, such as “Crocodylus” blavieri? Grey from the Upper Campanian - Maastrichtian of Viso, near Aveiro (initially reported by Sauvage 1897-98), Goniopholis cf. crassidens Owen 1841 and Oweniasuchus pulchelus Jonet 1981. Moreover there is a fascinating, but poorly understood, crocodylomorph diversity in the Cenomanian of Portugal, documented by fragmentary specimens that have been doubtfully assigned to Thoracosaurus Leidy 1852 of the Middle Cenomanian of Cacém, to the nomen dubium Oweniasuchus lusitanicus Sauvage 1897-98 (interpreted as a mesosuchian goniopholid) based in a fragmentary mandible from the Campanian-Maastrichtian, and also from the Middle Cenomanian of Portugal, Buffetaut and Lauverjat (1978) report an fragmentary unidentified possible dyrosaurid from Nazaré. All this specimens are too incomplete to be compared with the specimen here described. In contrast, Cenozoic crocodiles of Portugal are often known after complete skulls and several individuals. The taxa list include Iberosuchus macrodon (Lower to Middle Eocene), Tomistoma calaritanus (Early Miocene) and T. lusitanica (Burdigalian-Helvetian), and Diplocynodon sp. (Antunes, 1961, 1987, 1994).
At least, two different morphotypes of crocodylomorph eggs from the Late Jurassic of Lourinhã Formation are also known.
A new specimen here reported of crocodile based in a partial skull and mandible (ML1818) from the Uppermost Middle Cenomanian platform carbonates of Baixo Mondego, west central Portugal (Tentúgal Fm., Callapez, 2004). The taxon is phylogenetically positioned as a basal Eusuchia, due to the choanae enclosed by the pterygoid, and closely related with stem Crocodylia and Borealosuchus. This specimen represents the only well documented and valid eusuchian species in the Cenomanian of Europe and is the oldest representative of an eusuchian crocodylomorph, with the exception for the Barremian Hylaeochampsa vectiana.

Mateus, O. (2012).  Age and paleoecology of mosasaurs and plesiosaurs from the Late Cretaceous South Atlantic margin at Bentiaba, Angola. Journal of Vertebrate Paleontology, Program and Abstracts, 2012. 180.. 180–181., 1 Abstract
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Mateus, I., Mateus H., Antunes M. T., Mateus O., Taquet P., Ribeiro V., & Manuppella G. (1997).  Couvée, oeufs et embryons d'un dinosaure théropode du Jurassique supérieur de Lourinhã (Portugal). C.R Acad. Sci. Paris, Sciences de la terre et des planetes. 325, 71-78., Jully, Number 1 Abstractmateus_et_al_1997_eggs_embryos_nest__couvee_oeufs_et_embryons_dun_dinosaure_theropode_du_jurassique_superieur_de_lourinha_portugal.pdfWebsite

Several well preserved clutches of dinosaurs have been discovered in the upper Kimmeridgian/ Tithonian of Lourinhã (Estramadur Province, Portugal). Some eggs of one clutch contained embryo elements of a theropod dinosaur. The egg-shell resembles that of eggs which have been discovered in the Upper Jurassic of Colorado

Mateus, O., Mateus O., Jacobs L. L., Schulp A. S., Polcyn M. J., Tavares T. S., Neto A. B., Morais M. L., & Antunes M. T. (2011).  Angolatitan adamastor, a new sauropod dinosaur and the first record from Angola. Anais da Academia Brasileira de Ciências. Abstract
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Mateus, O., & Antunes M. T. (2002).  Novos vestígios de dinossauros saurópodes do Jurássico Superior da Lourinhã (Portugal). Congresso Ibérico de Herpetologia. , Évora Abstract
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Mateus, O. (2009).  Colecções paleontológicas do Museu da Lourinhã (Portugal) / Paleontological collections of the Museum of Lourinhã (Portugal). (Unknown Unknown, Ed.).Journal of Paleontological Techniques. 18–19.., 1 Abstract
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Mateus, O. (2016).  Exemplos bizarros de evolução em dinossauros e alguns casos portugueses. Do Big Bang ao Homem. 81-95., Porto: U.Porto Ediçõesmateus_2016_capitulo_livro_dinosaurs.pdf
Mateus, I., Mateus H., Antunes M. T., Mateus O., Taquet P., Ribeiro V., & Manuppella G. (1997).  Couvée, oeufs et embryons d'un dinosaure théropode du Jurassique supérieur de Lourinhã (Portugal). Comptes Rendus de l'Académie des Sciences-Series IIA-Earth and Planetary Science. 325, 71–78., Number 1 Abstract
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Mateus, O. (2012).  New dinosaur and pterosaur tracksites from the Late Jurassic of Portugal. , Chongqing, China: 2012 Abstract Book of Qijiang International Dinosaur Tracks Symposium Abstractmateus_2012_dinosaur_tracks_portugal__abstract_book_qijiang_int_dinosaur_tracks_symposium.pdf

Portugal is rich on dinosaur remains (bones, eggs, and tracks) from Early Jurassic to Late
Cretaceous ages, but mainly from the Late Jurassic, in which dozen of tracksites have been reported.
Here are reported new or poorly known track localities:
1) Five tracksites share the preservation substrate (marine carbonated limestone), age (late Jurassic), geographic area (Leiria district of Portugal), kind of preservation (true tracks), and completeness (trackways of multiple individuals):
i) Praia dos Salgados includes eight trackways, mostly ornithopods and theropods, and one wide gauge sauropod, made in very soft sediment; some preserve the hallux impression.
ii) Serra de Mangues is mostly covered with vegetation but seems to include dozens of tracks comprising theropods, thyreophorans, ornithopods and sauropods.
iii) Sobral da Lagoa (Pedreira do Rio Real) include six trackways but poorly preserved;
and
iv) Serra de Bouro that preserves four sauropod trackways in one single layer.
v) Pedrógão, preserved, at least, one theropod trackway and several isolated tracks of
theropods and ornithopods were found in different layers in the Early Oxfordian.
2) The locality in Praia de Porto das Barcas yielded natural casts of stegosaur tracks
(including pes print with skin impression) and a very large sauropod pes print with about
1.2 m long pes.
3) A new pterosaur tracksite was found in the Late Jurassic of Peralta, Lourinhã (Sobral Member, Lourinhã Fm.; Late Kimmeridgian/Early Tithonian). More than 220 manus and pes tracks have been collected in about five square meters, all ascribed to pterosaurs. The tracks were produced in a thin mud layer that has been covered by sand which preserved them as sandstone mould infill (natural casts). The manus of the largest specimens is 13 cm wide and 5.5 cm long and the pes measures 14.5 cm in length and 9 cm in width. This shows the occurrence of very large pterosaurs in the Late Jurassic. Other pterosaur tracksites in the Late Jurassic of Portugal are: Porto das Barcas (Lourinhã Municipality), South of Consolação (Peniche Municipality), and Zambujal de Baixo (Sesimbra Municipality).

Mateus, O., Mannion P. D., & Upchurch P. (2014).  Zby atlanticus, a new turiasaurian sauropod (Dinosauria, Eusauropoda) from the Late Jurassic of Portugal. Journal of Vertebrate Paleontology. 34, 618-634., Number 3 Abstract
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Mateus, O., Maidment S., & Christiansen N. (2009).  A new long-necked 'sauropod-mimic' stegosaur and the evolution of the plated dinosaurs. Proceedings of the Royal Society of London B. 276, 1815-1821., Jan Abstractmateus_et_al_2009_stegosaur_miragaia_complete_with_suppl.pdfWebsite

Stegosaurian dinosaurs have a quadrupedal stance, short forelimbs, short necks, and are generally considered to be low browsers. A new stegosaur, Miragaia longicollum gen. et sp. nov., from the Late Jurassic of Portugal, has a neck comprising at least 17 cervical vertebrae. This is eight additional cervical vertebrae when compared with the ancestral condition seen in basal ornithischians such as Scutellosaurus.
Miragaia has a higher cervical count than most of the iconically long-necked sauropod dinosaurs. Long neck length has been achieved by ‘cervicalization’ of anterior dorsal vertebrae and probable lengthening of centra. All these anatomical features are evolutionarily convergent with those exhibited in the necks of
sauropod dinosaurs. Miragaia longicollum is based upon a partial articulated skeleton, and includes the only known cranial remains from any European stegosaur. A well-resolved phylogeny supports a new clade that unites Miragaia and Dacentrurus as the sister group to Stegosaurus; this new topology challenges the common view of Dacentrurus as a basal stegosaur.

Mateus, O. (2011).  Plesiosaur structural extreme from the Maastrichtian of Angola. Abstracts of the 71st Annual Meeting of the Society of Vertebrate Paleontology. 63., 1 Abstract
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Mateus, O., & Jacinto J. J. (2002).  Contribuição para o estudo de Hemidactylus turcicus (Reptilia, Gekkonidae): ritmos de actividade e microhabitat em Évora, Portugal. VII Congresso Luso-Espanhol de Herpetologia. 136–136., Évora Abstract
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Mateus, O. (1999).  Monofilia dos dinossauros e Origem das Aves: Serão as aves dinossauros?. (P, P Catry, F Moreira, Ed.).Actas do II Congresso de Ornitologia. 184-185., Lisboa: SPEA- Sociedade Portuguesa para o Estudo das Aves Abstract
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Mateus, O. (2014).  Elephas and other vertebrate fossils near Taghrout, Morocco. Journal of Vertebrate Paleontology. Program and Abstracts, 2014, 178., 1 Abstract
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Mateus, O., Taquet P., Antunes M. T., Mateus H., & Ribeiro V. (1998).  Theropod dinosaur nest from Lourinhã, Portugal. Journal of Vertebrate Paleontology. 18, 61., Number (Suppl. 3) Abstract
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Mateus, O. (2006).  The European Enigmatic Dinosaur Evolution [in Japanese]. The Gigantic dinosaur Expo 2006 (catalogue). 69-71.mateus_2006_european.pdf
Mateus, O. (2008).  Checklist for Late Jurassic reptiles and amphibians from Portugal. Livro de Resumos do X Congresso Luso-Espanhol de Herpetologia. 55., Coimbra Abstract
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Mateus, O., & Castanhinha R. (2008).  PaleoAngola- Predadores de um oceano primitivo. National Geographic Portugal. 8, 26-33., Number 91 Abstract
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Mateus, O., Neto de Carvalho C., & Klompmaker A. A. (2013).  Decapod crustacean body and ichnofossils from the Mesozoic of Portugal. 5th Symposium on Mesozoic and Cenozoic Decapod Crustaceans. , 25–27 June 2013, Warszawa: Polish Geological Institute − National Research Institute & AGH University of Science and Technologymateus_et_al_2013_crustacea_mesozoic_portugal_5th_decapod_crustaceans_meeting_2013.pdf
Mateus, O. (2007).  Notes and review of the ornithischian dinosaurs of Portugal. Journal of Vertebrate Paleontology. 27(suppl. to 3), 114. Abstract
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Mateus, O., Jacobs L. L., Schulp A. S., Polcyn M. J., Tavares T. S., Neto A. B., Morais M. L., & Antunes M. T. (2011).  Angolatitan adamastor, a new sauropod dinosaur and the first record from Angola.. Anais da Academia Brasileira de Ciências. 83, 221-233., Jan Abstractmateus_et_al_2011_angolatitan_adamastor_sauropod.pdfWebsite

A forelimb of a new sauropod dinosaur (Angolatitan adamastor n. gen. et sp.) from the Late Turonian of Iembe (Bengo Province) represents the first dinosaur discovery in Angola, and is one of the few occurrences of sauropod dinosaurs in sub-Saharan Africa collected with good chronological controls. The marginal marine sediments yielding the specimen are reported to be late Turonian in age and, thus it represents a non-titanosaurian sauropod in sub-Saharan Africa at a time taken to be dominated by titanosaurian forms. Moreover, Angolatitan adamastor is the only basal Somphospondyli known in the Late Cretaceous which implies in the existence of relict forms in Africa.

Mateus, O., & Antunes T. M. (2001).  Draconyx loureiroi, a new camptosauridae (Dinosauria, Ornithopoda) from the Late Jurassic of Lourinhã, Portugal. Annales de Paleontologie. 87, 61-73. Abstractmateus_antunes_2001_draconyx_loureiroi_a_new_camptosauridae_dinosauria_ornithopoda_from_the_late_jurassic_of_lourinha_portugal.pdfWebsite

A new ornithopod dinosaur is described here under the name of Draconyx loureiroi n. gen., n. sp. on teeth, caudal vertebrae, forelimb, hindlimb, and foot material that were found in association in the Late Jurassic-Tithonian of Lourinhã, Portugal. Draconyx is a Camptosauridae related to Camptosaurus.

Mateus, O. (2011).  Evolutionary major trends of ornithopod dinosaurs teeth. (Unknown Unknown, Ed.).Dinosaurios y paleontología desde América Latina. 25–31., 1: EDIUNC, Editorial de la Universidad Nacional de Cuyo Abstract
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Mateus, O., & Antunes M. T. (2000).  Ceratosaurus sp. (Dinosauria: Theropoda) in the Late Jurassic of Portugal. Abstract volume of the 31st International Geological Congress. , Rio de Janeiro, Brazil Abstractmateus__antunes_2000_-_ceratosaurus_in_portugal.pdf

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Mateus, O. (2014).  Cracking dinosaur endothermy: paleophysiology unscrambled. NA, , 1 Abstract

The amniote eggshell functions as a respiratory structure adapted for the optimal transmission of respiratory gasses to and from the embryo according to its physiological requirements. Therefore amniotes with higher oxygen requirements, such as those that sustain higher metabolic rates, can be expected to have eggshells that can maintain a greater gas flux to and from the egg. Studies of extant amniotes have found that eggshells of reduced porosity impose a limit on the metabolic rate of the offspring. Here we show a highly significant relationship between metabolic rates and eggshell porosity in extant amniotes that predicts highly endothermic metabolic rates in dinosaurs. This study finds the eggshell porosity of extant endotherms to be significantly higher than that of extant ectotherms. Eggshell porosity values of dinosaurs are found to be significantly higherthan that of extant ectotherms, but not extant endotherms. Dinosaur eggshells are commonly preserved in the fossil record, and porosity may be readily identified and measured. This provides a simple tool to identify metabolic rates in extinct egg-laying tetrapods whose eggs possessed a mineralized shell