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2011
Adams, T. L., Polcyn M. J., Mateus O., Winkler D. A., & Jacobs L. L. (2011).  First occurrence of the long-snouted crocodyliform Terminonaris (Pholidosauridae) from the Woodbine Formation (Cenomanian) of Texas. Journal of Vertebrate Paleontology. 31, 712-716., Number 3 Abstract
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Martins, R. M. S., Beckmann F., Castanhinha R., Araújo R., O. Mateus, & Pranzas P. K. (2011).  Tomographic techniques for the study of exceptionally preserved dinosaur and crocodile fossils from the mesozoic of Portugal. VII Encontro Nacional de Biologia Evolutiva, Coimbra, 21 Dezembro 2011. 19. Abstractmartins_et_al_mateus_2011_tomographic_techniques_for_the_study_of_exceptionally_preserved_dinosaur_and_crocodile.pdf

Portugal is ranked within the ten countries with more dinosaur taxa and the Lourinhã Formation is known
by the Late Jurassic findings of dinosaurs and other fossils. Often, studies of the external morphological
characteristics of the fossils are not sufficient and, observations of internal structures, using non-
destructive techniques, are required. The fossils here presented belong to the Museum da Lourinhã
(Portugal) and comprise a lower jaw of a basal crocodilian (possibly a Tomistomidae), eggshells and
several vertebrae from the exceptionally well preserved in ovo remains of Late Jurassic theropod dinosaur
Lourinhanosaurus. Neutron Tomography (NT) experiments with this material has been carried out at the
Geesthacht Neutron Facility in Germany. Additionally, eggshell fragments and several vertebrae have
been studied by Synchrotron-Radiation based Micro-Computed Tomography (SRμCT) at the HARWI II and
BW2 beamlines, respectively. These beamlines are operated by the Helmholtz-Zentrum Geesthacht at the
storage ring DORIS III at the Deutsches Elektronen–Synchrotron DESY in Hamburg, Germany. In both cases
(NT and SRμCT) complete 3D recordings have been obtained using a non-destructive procedure. The high-
quality tomographic datasets can be effectively studied through interactive digital visualization. Hence,
these visualization methods provide precious information about the 3D internal micro morphology of
fossils, like the network of the eggshell pores, often invisible in more traditional techniques, and provide a
direct window into the evolutionary history of organisms.

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.

Adams, T. L., Polcyn M. J., Mateus O., Winkler D. A., & Jacobs L. L. (2011).  First occurrence of the long-snouted crocodyliform Terminonaris (Pholidosauridae) from the Woodbine Formation (Cenomanian) of Texas. Journal of Vertebrate Paleontology. 31, 712-716., Jan: So Methodist Univ, Univ Nova Lisboa Abstractadams_polcyn_mateus_et_al_2011_terminonaris_crocodile_pholidosauridae.pdf

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Graf, J., Jacobs L. L., Polcyn M. J., Mateus O., & Schulp A. S. (2011).  New fossil whales from Angola. 71st Annual Meeting of the Society of Vertebrate Paleontology. 119., Jan: Abstracts of the 71st Annual Meeting of the Society of Vertebrate Paleontologygraf_et_al_mateus_2011_fossil_whales_from_angola_svp11abstracts.pdf
Araújo, R., Polcyn M., Jacobs L. L., Mateus O., & Schulp A. S. (2011).  Plesiosaur structural extreme from the Maastrichtian of Angola. 71st Annual Meeting of the Society of Vertebrate Paleontology. 63., Jan: Abstracts of the 71st Annual Meeting of the Society of Vertebrate Paleontology Abstractaraujo_et_al_mateus_2011_plesiosaur_extreme_angola_svp11abstracts.pdf

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2012
Strganac, C., Ferguson, K.M, Jacobs J. L., Polcyn M. J., & 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.strganac_et_al_mateus_2012_age_bentiaba_angola_2012_svp_abstract.pdf
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.

Vineyard, D., Mateus O., Jacobs L. L., Polcyn M. J., & Schulp A. (2012).  A new marine turtle from the Maastrichtian of Angola. Journal of Vertebrate Paleontology, Program and Abstracts, 2012, 189. ISSN 1937-2809 . 189.vineyard_mateus_et_al_2012_euclastes_chelonia_turtle_angola_svp_2012_abstract.pdf
Martins, R. M. S., Beckmann F., Castanhinha R., Mateus O., Araújo R., & Pranzas P. K. (2012).  Synchrotron radiation-based micro-computed tomography applied to the characterization of dinosaur fossils from the Lourinhã Formation. 1 st . Meeting of Synchrotron Radiation Users from Portugal. 1-2., Caparica, Portugalmartins_et_al_2012_tomography_enurs_martins-rui_dinosaurfossils.pdf
Martins, R. M. S., Araújo R., Mateus O., Castanhinha R., Pranzas P. K., & Beckmann F. (2012).  Tomography applied to the study of dinosaur fossils from the collection of the museum of Lourinhã (Portugal). I Congresso Internacional GeoCiencias na CPL. , Coimbra: Univ. Coimbramartins_et_al_2012_abstract.pdf
2013
Schulp, A. S., Polcyn M. J., Mateus O., & Jacobs L. L. (2013).  Two rare mosasaurs from the Maastrichtian of Angola and the Netherlands. Geologie en Mijnbouw/Netherlands Journal of Geosciences. 92, 3-10., Number 1 Abstract
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Bianucci, G., Miján I., Lambert O., Post K., & Mateus O. (2013).  Bizarre fossil beaked whales (Odontoceti, Ziphiidae) fished from the Atlantic Ocean floor off the Iberian Peninsula. Geodiversitas. 35(1), 105-153. Abstractbianucci_et_al_2013_fossil_beaked_whales_iberian_peninsula.pdf

Forty partial fossil skulls belonging to beaked whales (Cetacea, Odontoceti, Ziphiidae) were collected by trawling and long-line fishing on Neogene (probably Late Early to Middle Miocene) layers of the Atlantic floor off the coasts of Portugal and Spain (Asturias and Galicia). e systematic study of the most diagnostic Iberian specimens, those preserving the rostrum and the dorsal part of the cranium, led to the recognition of two new genera (Globicetus n. gen. and Imocetus n. gen.) and four new species (Choneziphius leidyi n. sp., G. hiberus n. gen., n. sp., I. piscatus n. gen., n. sp., and Tusciziphius atlanticus n. sp.).
Based on the matrix of a previous work, the phylogenetic analysis places all the new taxa in the subfamily Ziphiinae Gray, 1850. More fragmentary specimens are tentatively referred to the genera Caviziphius Bianucci & Post, 2005 and Ziphirostrum du Bus, 1868. Among these new ziphiids, extremely bizarre skull morphologies are observed. In G. hiberus n. gen., n. sp. the proximal portion of the rostrum bears a voluminous premaxillary spheroid. In T. atlanticus n. sp. a medial premaxillary bulge is present on the rostrum; together with asymmetric
rostral maxillary eminences at the rostrum base, this bulge displays various degrees of elevation in different specimens, which may be interpreted as sexual dimorphism. Specimens of I. piscatus n. gen., n. sp. bear two sets of even crests: spur-like rostral maxillary crests and longitudinal maxillary crests laterally bordering a wide and long facial basin. A preliminary macroscopic observation of these elements indicates very dense bones, with a compactness comparable with that of cetacean ear bones. Questioning their function, the high medial rostral elements (the premaxillary spheroid of G. hiberus n. gen., n. sp. and the medial bulge of T. atlanticus n. sp.) remind the huge rostral maxillary crests of adult males of the extant Hyperoodon ampullatus (Forster, 1770). In the latter, the crests are very likely related to head-butting. However, they are made of much more spongy bone than in the fossil taxa studied here, and therefore possibly better mechanically suited for facing impacts. Other interpretations of these unusual bone specializations, related to deep-diving (ballast) and echolocation (sound reflection), fail to explain the diversity of shapes and the hypothetical sexual dimorphism observed in at least part of the taxa. e spur-like rostral maxillary crests and long maxillary crests limiting the large facial basin in I. piscatus n. gen., n. sp. and the excrescences on the maxilla at the rostrum base in Choneziphius spp. are instead interpreted as areas of origin for rostral and facial muscles, acting on the nasal passages, blowhole, and melon. From a palaeobiogeographic point of view, the newly described taxa further emphasize the differences in the North Atlantic (including Iberian Peninsula) and South African Neogene ziphiid faunal lists. Even if the stratigraphic context is poorly understood, leaving open the question of the geological age for most of the dredged specimens, these differences in the composition of cold to temperate northern and southern hemisphere fossil ziphiid faunas may be explained by a warm-water equatorial barrier.

Jacobs, L. L., Myers T. S., Goncalves A. O., Graf J. F., Jacobs B. F., KAPPELMAN J. W., Mateus O., Polcyn M. J., RASBURY E. T., & Vineyard D. P. (2013).  Cabinda revisited: age and environment of new Cenozoic vertebrate fossils from northern Angola. Geological Society of America Abstracts with Programs. Vol. 45, No. 7, p.0.
Strganac, C., Jacobs L. L., Ferguson K. M., Polcyn M. J., Mateus O., Schulp A. S., & Morais M. L. (2013).  Late Cretaceous marine reptiles and cooling at the South Atlantic coast inferred through stable oxygen isotopes of Inoceramus from the Namibe Basin, Angola. Geological Society of America Abstracts with Programs. Vol. 45, No. 7, p.0.
Polcyn, M. J., Jacobs L. L., Mateus O., Schulp A. S., Strganac C., Araújo R., Graf J. F., Vineyard D., & Myers T. S. (2013).  A marine vertebrate assemblage from the Campanian-Maastrichtian boundary at Bentiaba, Angola. Geological Society of America Abstracts with Programs. Vol. 45, No. 7, p.0. polcyn_et_al_2013_abstract__a_marine_vertebrate_assemblage_from_the_campanian-maastrichtian_boundary_at_bentiaba_angola_2013__gsa_27-30_october_2013.pdf
Schulp, A. S., Polcyn M. J., Mateus O., & Jacobs L. L. (2013).  Two rare mosasaurs from the Maastrichtian of Angola and the Netherlands. Netherlands Journal of Geosciences — Geologie en Mijnbouw. 92(1), 3-10. Abstractschulp_et_al_2013_two_rare_mosasaurs_from_the_maastrichtian_of_angola__njg-92-1-schulp.pdf

We report here the addition of two rare mosasaur taxa to the Maastrichtian marine amniote fauna of Angola. The new specimens include a dentary fragment referable to the large carnivore Prognathodon saturator and an isolated tooth of the small durophage Carinodens belgicus. Both were recovered from Maastrichtian outcrops in southern Angola in 2011. Additionally, a complete posterior mandibular unit of a large mosasaur from the type Maastrichtian of The Netherlands, collected some time prior to 1879 and previously identified as ‘Mosasaurus giganteus’, is described and reassigned here to Prognathodon saturator; historical issues surrounding the taxonomic attribution of this specimen are clarified. The new material extends the known geographic distribution of Prognathodon saturator and Carinodens belgicus.

Pais, {J. J. C. }, Kullberg {J. C. R. }, de} Melo {J. M. D. J., Mateus O., & de} Almeida {J. A. (2013).  Arrábida - al-rábita. , 1: Associação de Municípos da Região de Lisboa Abstract

The publication of the present work - rightly designated as the book of Arrabida's nomination file for inscription on the World Heritage list - has for all of us a special significance as it represents, in a sense, the culmination of a complex, challenging and rewarding process. As is widely known, the Arrábida is included since 2004 in UNESCO's Portuguese tentative list, with AMRS being one of this process' promoters. It wouldn't be appropriate to describe here all the details, but it is fair to say that since 2004 to the present day, we've come a long way in recovering and valuing the Arrábida. It is with sincere satisfaction that we can say: our knowledge of the Property is now deeper, up to date and much more accurate, doing justice to the exceptional values contained within the Arrábida - which is well expressed in the work now published, based on researches and works of the highest scientific value. This is also a regional development project, to value our lands, people and the natural and cultural heritage. The Setúbal's Peninsula is a region that contains within its territory a vast natural and cultural heritage, being the Arrábida one of the most beautiful and significant natural areas in the Mediterranean. The Arrábida Mountain is a place with its own identity, being the result of a long history of Man's adaptation to Nature. It is a place of unmistakable aesthetic beauty, a unique place where nature and culture intertwine; it is a place of contrasts, of land and sea, sky and mountains, a place of combined actions by Man and Nature. Place of vibrant social practices, of rituals and festivals, of knowledge, of representations and expressions, of instruments, objects and artifacts. Place with a history that must be preserved and bequeathed to future generations. Place with monuments of vanished civilizations, but also of living traditions. These are some of the values supporting the Arrábida's nomination for the World's Heritage list. It is a complex and demanding nomination file, which this work is an illustrative sample of. A mixed application - as it includes both the natural and cultural heritage - which, given the richness and uniqueness of the Property in question, is fully justified. It is our profound conviction that this Nomination streamlines the potential of our region, bringing benefits not only to the local population, but also to the whole country. To that extent, it is also a sign of hope and confidence showing that it is possible to build a different future; that by investing in our people, in their abilities, knowledge and traditions, it is possible to create a sustainable development; that is possible to leave for future generations a legacy of which we are proud of having worked on. To be able enjoy this magnificent edition is a step in that direction.

da} Rocha, {R. E. B., Kullberg {J. C. R. }, & Mateus O. (2013).  A Bacia Lusitaniana: Estratigrafia, Paleogeografia e Tectónica. (Dias, Araújo, R., A, Terrinha, P., Kullberg, {J. C.}, Ed.).Geologia de Portugal no contexto da Ibéria. 195–347., 1: Escolar Editora Abstract
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2014
Strganac, C., Salminen J., Jacobs L. L., Polcyn M. J., Ferguson K. M., Mateus O., Schulp A. S., Morais M. L., Tavares T. S., & Gon?alves A. O. (2014).  Carbon isotope stratigraphy, magnetostratigraphy, and 40Ar/39Ar age of the cretaceous South Atlantic coast, Namibe Basin, Angola. Journal of African Earth Sciences. 99, 452-462., Number PA2 Abstract
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Strganac, C., Jacobs L. L., Polcyn M. J., Mateus O., Myers T. S., Salminen J., May S. R., Araújo R., Ferguson K. M., Gon?alves A. O., Morais M. L., Schulp A. S., & da Silva Tavares T. (2014).  Geological setting and paleoecology of the Upper Cretaceous Bench 19 Marine Vertebrate Bonebed at Bentiaba, Angola. Geologie en Mijnbouw/Netherlands Journal of Geosciences. 94, 121-136., Number 1 Abstract
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Araújo, R., Polcyn M. J., Lindgren J., Jacobs L. L., Schulp A. S., Mateus O., Gon?alves A. O., & Morais M. - L. (2014).  New aristonectine elasmosaurid plesiosaur specimens from the Early Maastrichtian of Angola and comments on paedomorphism in plesiosaurs. Geologie en Mijnbouw/Netherlands Journal of Geosciences. 94, 93-108., Number 1 Abstract
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Araújo, R., Polcyn M. J., Schulp A. S., Mateus O., Jacobs L. L., Gon?alves A. O., & Morais M. - L. (2014).  A new elasmosaurid from the early Maastrichtian of Angola and the implications of girdle morphology on swimming style in plesiosaurs. Geologie en Mijnbouw/Netherlands Journal of Geosciences. 94, 109-120., Number 1 Abstract
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Polcyn, M. J., Jacobs L. L., Araújo R., Schulp A. S., & Mateus O. (2014).  Physical drivers of mosasaur evolution. Palaeogeography, Palaeoclimatology, Palaeoecology. 400, 17-27. Abstract
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Strganac, C., Jacobs L. L., Polcyn M. J., Ferguson K. M., Mateus O., Gon?alves A. O., Morais M. - L., & da Silva Tavares T. (2014).  Stable oxygen isotope chemostratigraphy and paleotemperature regime of mosasaurs at Bentiaba, Angola. Geologie en Mijnbouw/Netherlands Journal of Geosciences. 94, 137-143., Number 1 Abstract
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Strganac, C., Salminen J., Jacobs L. L., Ferguson K. M., Polcyn M. J., Mateus O., Schulp A. S., Morais M. L., Tavares T. S., & Gonçalves A. O. (2014).  Carbon isotope stratigraphy and 40Ar/39Ar age of the Cretaceous South Atlantic coast, Namibe Basin, Angola. Journal of African Earth Sciences. onine, 1-11. Abstractstrganac_et_al_2014_carbon_isotope_stratigraphy_magnetostratigraphy_and_40ar_39ar_age_of.pdfWebsite

We present the δ13C and paleomagnetic stratigraphy for marine strata at the coast of southern Angola, anchored by an intercalated basalt with a whole rock 40Ar/39Ar radiometric age of 84.6 ± 1.5 Ma, being consistent with both invertebrate and vertebrate biostratigraphy. This is the first African stable carbon isotope record correlated to significant events in the global carbon cycle spanning the Late Cenomanian to Early Maastrichtian. A positive ∼ 3‰ excursion seen in bivalve shells below the basalt indicates the Cenomanian-Turonian Boundary Event at 93.9 Ma, during Oceanic Anoxic Event 2. Additional excursions above the basalt are correlated to patterns globally, including a negative ∼ 3‰ excursion near the top of the section interpreted as part of the Campanian-Maastrichtian Boundary Events. The age of the basalt ties the studied Bentiaba section to a pulse of Late Cretaceous magmatic activity around the South Atlantic and significant tectonic activity, including rotation, of the African continent.

Jacobs, L., Polcyn M., Mateus O., Scott M., Graf J., Kappelman J., Jacobs B., Schulp A., Morais M., & Goncalves O. (2014).  Cenozoic vertebrates of coastal Angola. Journal of Vertebrate Paleontology, Program and Abstracts, 2014. 153.jacobs_et_al._2014_cenozoic_vertebrates_of_coastal_angola.pdf
Marzola, M., Mateus O., Schulp A., Jacobs L., Polcyn M., & Pervov V. (2014).  Early Cretaceous tracks of a large mammaliamorph, a crocodylomorph, and dinosaurs from an Angolan diamond mine. Journal of Vertebrate Paleontology, Program and Abstracts, 2014. 181.marzola_et_al_2014._cretaceous_tracks_mammaliamorph_a_crocodilomorph_angolan_diamond_mine.pdf
Polcyn, M., Jacobs L., Strganac C., Mateus O., Myers S., May S., Araujo R., Schulp A., & Morais M. (2014).  Geology and paleoecology of a marine vertebrate bonebed from the lower Maastrichtian of Angola. Journal of Vertebrate Paleontology. Program and Abstracts, 2014, 206.polcyn_et_al._2014_geology_and_paleoecology_of_a_marine_vertebrate_bonebed_from_the_lower_maastrichtian_of_angola.pdf
Polcyn, M. J., Jacobs L. L., Ara´ujo R., Schulp A. S., & Mateus O. (2014).  Physical drivers of mosasaur evolution. Palaeogeography, Palaeoclimatology, Palaeoecology. 400, 17-27. Abstractpolcyn_et_al_2014_physical_drivers_mosasaurs.pdf

Mosasaurs are marine squamates with a 32.5 million-year history from their appearance at 98 Ma to their extinction at the K-Pg boundary (65.5 Ma). Using a database of 43 generic and 94 species-level taxa, we compare the taxonomic diversity and patterns of morphological disparity in mosasaurs with sea level, sea surface temperature, and stable carbon isotope curves for the Upper Cretaceous to explore factors that may have influenced their evolution. No single factor unambiguously accounts for all radiations, diversification, and extinctions; however, the broader patterns of taxonomic diversification and
morphological disparity point to niche differentiation in a “fishing up” scenario under the influence of “bottom-up” selective pressures. The most likely driving force in mosasaur evolution was high productivity in the Late Cretaceous, driven by tectonically controlled sea levels and climatically controlled ocean stratification and nutrient delivery. When productivity collapsed at the end of the Cretaceous, coincident with bolide impact, mosasaurs became extinct.

Polcyn, M. J., Jacobs L. L., Strganac C., Mateus O., Myers T. S., May S., Araújo R., Schulp A. S., & Morais M. L. (2014).  Geological and paleoecological setting of a marine vertebrate bonebed from the Lower Maastrichtian at Bentiaba, Angola. Secondary Adaptation of Tetrapods to Aquatic Life. , 2-4 Jun 2014, Washington DC, USA
2015
Marzola, M., Mateus O., Schulp A. S., Jacobs L. L., Polcyn M. J., Pervov V., Goncalves A. O., & Morais M. L. (2015).  Comparative anatomy and systematics of Cretaceous mammal tracks of Angola. 13th Annual Meeting of the European Association of Vertebrate Palaeontologists - EAVP 2015. , Opole, Poland Abstract
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Marzola, M., Mateus O., Schulp {A. S. }, Jacobs {L. L. }, Polcyn {M. J. }, Pervov V., Goncalves {A. O. }, & Morais {M. L. } (2015).  Comparative anatomy and systematics of Cretaceous mammal tracks of Angola. 35. Abstract
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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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Pereira, B. C., Benton M. J., Ruta M., & Mateus O. (2015).  Mesozoic echinoid diversity in Portugal: Investigating fossil record quality and environmental constraints on a regional scale. Palaeogeography, Palaeoclimatology, Palaeoecology. 424, 132-146. Abstract
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Xing, L., Lockley M. G., Marty D., Zhang J., Wang Y., Klein H., McCrea R. T., Buckley L. G., Belvedere M., Mateus O., Gierli?ski G. D., Piñuela L., Persons W. S., Wang F., Ran H., Dai H., & Xie X. (2015).  An ornithopod-dominated tracksite from the lower Cretaceous Jiaguan Formation (Barremian-Albian) of Qijiang, South-Central China: New discoveries, ichnotaxonomy, preservation and palaeoecology. PLoS ONE. 10, , Number 10 Abstract
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Polcyn, {M. J. }, Jacobs L. L., Schulp A. S., & Mateus O. (2015).  Tethyan and Weddellian biogeographic mixing in the Maastrichtian of Angola. : Journal of Vertebrate Paleontology Abstract
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Polcyn, {M. J. }, Jacobs {L. L. }, Schulp {A. S. }, & Mateus O. (2015).  Trolling the Cretaceous Seas: Marine Amniotes of Two West Coast Margins. : Geological Society of America Abstracts with Programs. Vol. 47, No. 4, p.55 Abstract

In this session we review the Upper Cretaceous marine amniote records from the west coasts of North America and Africa. Recent work by our group in Angola, on the west coast of Africa, has opened up new fossiliferous localities, producing well-preserved turtles, plesiosaurs, and mosasaurs, ranging in age from Late Turonian to Late Maastrichtian. These African localities were deposited in arid latitudes and highly productive upwelling zones along the passive margin of a growing South Atlantic Ocean. The fossil record of Cretaceous marine amniotes from the West Coast of North America is relatively meager when compared to the African record and the prolific fossil beds laid down in the epicontinental seas of the Western Interior Seaway and northern Europe. Nonetheless, these localities provide an important glimpse of a marine ecosystem that developed on the active margins of a deep ocean basin. Historically considered to be depauperate and endemic, the west coast fauna was characterized by unusual forms such as Plotosaurus, arguably one of the most derived mosasaurs; however, in recent years, additional taxa have been described, revealing species diversity and ecological partitioning within these communities and in some cases, faunal interchange with other regions. The large quantity of well-preserved fossils from the west coast of Africa is influenced in part by its paleogeographic position, deposited within highly productive areas of Hadley Cell controlled upwelling zones. By contrast, the North American west coast localities have been deposited in temperate and higher latitudes since the Late Cretaceous. Nonetheless, the North American and African faunas share some common characteristics in a possessing a mix of endemic and more cosmopolitan forms. Habitat partitioning reflected in tooth form and body size is comparable between the Angolan and the North American west coast, and there is remarkable convergence in taxa which appear to exploit certain like-niches.

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. Society of Vertebrate Paleontology Annual Meeting. 177., Dallasmateus_et_al_2015_testudines_angola_svp_abstract.pdf
Strganac, C., Jacobs L., Polcyn M., Mateus O., Myers T., Araújo R., Fergunson K. M., Gonçalves A. O., Morais M. L., Schulp A. S., da Tavares T. S., & Salminen J. (2015).  Geological Setting and Paleoecology of the Upper Cretaceous Bench 19 Marine Vertebrate Bonebed at Bentiaba, Angola. Netherlands Journal of Geosciences. 94(1), 121-136. Abstractstrganac_et_al_2014_geological_setting_bentiaba_angola.pdfWebsite

The Bench 19 Bonebed at Bentiaba, Angola, is a unique concentration of marine vertebrates preserving six species of mosasaurs in sediments best correlated by magnetostratigraphy to chron C32n.1n between 71.4 and 71.64 Ma. The bonebed formed at a paleolatitude near 24°S, with an Atlantic width at that latitude approximating 2700 km, roughly half that of the current width. The locality lies on an uncharacteristically narrow continental shelf near transform faults that controlled the coastal outline of Africa in the formation of the South Atlantic Ocean. Biostratigraphic change through the Bentiaba section indicates that the accumulation occurred in an ecological time dimension within the 240 ky bin delimited by chron 32n.1n. The fauna occurs in a 10 m sand unit in the Mocuio Formation with bones and partial skeletons concentrated in, but not limited to, the basal 1–2 m. The sediment entombing the fossils is an immature feldspathic sand shown by detrital zircon ages to be derived from nearby granitic shield rocks. Specimens do not appear to have a strong preferred orientation and they are not concentrated in a strand line. Stable oxygen isotope analysis of associated bivalve shells indicates a water temperature of 18.5°C. The bonebed is clearly mixed with scattered dinosaur and pterosaur elements in a marine assemblage. Gut contents, scavenging marks and associated shed shark teeth in the Bench 19 Fauna indicate biological association and attrition due to feeding activities. The ecological diversity of mosasaur species is shown by tooth and body-size disparity and by δ13C analysis of tooth enamel, which indicate a variety of foraging areas and dietary niches. The Bench 19 Fauna was formed in arid latitudes along a coastal desert similar to that of modern Namibia on a narrow, tectonically controlled continental shelf, in shallow waters below wave base. The area was used as a foraging ground for diverse species, including molluscivorus Globidens phosphaticus, small species expected near the coast, abundant Prognathodon kianda, which fed on other mosasaurs at Bench 19, and species that may have been transient and opportunistic feeders in the area.

Pereira, B. C., Benton M. J., Ruta M., & Mateus O. (2015).  Mesozoic echinoid diversity in Portugal: Investigating fossil record quality and environmental constraints on a regional scale. Palaeogeography, Palaeoclimatology, Palaeoecology. 424, 132 - 146. Abstractpereira_e_al_2015_mesozoic_echinoids_portugal.pdfWebsite

Abstract Several analyses of diversity through geological time use global, synoptic databases, and this practice often makes it difficult to distinguish true signals in changing diversity from regional-scale sampling and/or geological artefacts. Here we investigate how echinoid diversity changed through the Mesozoic of the Lusitanian basin in Portugal based on a comprehensive, revised database, and seek to distinguish biological signal from geological or environmental constraints. The observed diversity pattern is far from having a defined trend, showing many fluctuations that appear to be linked with gaps in the geological record. This study revealed that, independently of the method used, whether correlation tests or model fitting, the diversity signal is not completely explained by the studied sampling proxies. Among the different proxies, marine facies variation in combination with outcrop area best explains the palaeodiversity curve.

Polcyn, M. J., Jacobs L. L., Schulp A. S., Mateus O., & Araújo R. (2015).  Tethyan and Weddellian biogeographic mixing in the Maastrichtian of Angola. Annual Meeting of the Society of Vertebrate Paleontology. 196., Dallas, TXpolcyn_etal2015_mix_fauna_angola_svp_abstract.pdf
Polcyn, M. J., Jacobs L. L., Schulp A. S., & Mateus O. (2015).  Trolling the Cretaceous Seas: Marine Amniotes of Two West Coast Margins. Geological Society of America Annual Meeting. 55.: Geological Society of America Abstracts with Programs. Vol. 47, No. 4, p.55 Abstract

In this session we review the Upper Cretaceous marine amniote records from the west coasts of North America and Africa. Recent work by our group in Angola, on the west coast of Africa, has opened up new fossiliferous localities, producing well-preserved turtles, plesiosaurs, and mosasaurs, ranging in age from Late Turonian to Late Maastrichtian. These African localities were deposited in arid latitudes and highly productive upwelling zones along the passive margin of a growing South Atlantic Ocean. The fossil record of Cretaceous marine amniotes from the West Coast of North America is relatively meager when compared to the African record and the prolific fossil beds laid down in the epicontinental seas of the Western Interior Seaway and northern Europe. Nonetheless, these localities provide an important glimpse of a marine ecosystem that developed on the active margins of a deep ocean basin. Historically considered to be depauperate and endemic, the west coast fauna was characterized by unusual forms such as Plotosaurus, arguably one of the most derived mosasaurs; however, in recent years, additional taxa have been described, revealing species diversity and ecological partitioning within these communities and in some cases, faunal interchange with other regions. The large quantity of well-preserved fossils from the west coast of Africa is influenced in part by its paleogeographic position, deposited within highly productive areas of Hadley Cell controlled upwelling zones. By contrast, the North American west coast localities have been deposited in temperate and higher latitudes since the Late Cretaceous. Nonetheless, the North American and African faunas share some common characteristics in a possessing a mix of endemic and more cosmopolitan forms. Habitat partitioning reflected in tooth form and body size is comparable between the Angolan and the North American west coast, and there is remarkable convergence in taxa which appear to exploit certain like-niches.

Araújo, R., Polcyn M. J., Schulp A. S., Mateus O., Jacobs L. L., Gonçalves O. A., & Morais M. - L. (2015).  A new elasmosaurid from the early Maastrichtian of Angola and the implications of girdle morphology on swimming style in plesiosaurs. Netherlands Journal of Geosciences. FirstView, 1–12., 1 Abstractaraujo_et_al_2015_a_new_elasmosaurid_from_the_early_maastrichtian_of_angola.pdfWebsite

ABSTRACT We report here a new elasmosaurid from the early Maastrichtian at Bentiaba, southern Angola. Phylogenetic analysis places the new taxon as the sister taxon to Styxosaurus snowii, and that clade as the sister of a clade composed of (Hydrotherosaurus alexandrae (Libonectes morgani + Elasmosaurus platyurus)). The new taxon has a reduced dorsal blade of the scapula, a feature unique amongst elasmosaurids, but convergent with cryptoclidid plesiosaurs, and indicates a longitudinal protraction-retraction limb cycle rowing style with simple pitch rotation at the glenohumeral articulation. Morphometric phylogenetic analysis of the coracoids of 40 eosauropterygian taxa suggests that there was a broad range of swimming styles within the clade.

Xing, L., Lockley M. G., Marty D., Zhang J., Wang Y., Klein H., McCrea R. T., Buckley L. G., Belvedere M., Mateus O., Gierliński G. D., Piñuela L., Persons, IV S. W., Wang F., Ran H., Dai H., & Xie X. (2015).  An Ornithopod-Dominated Tracksite from the Lower Cretaceous Jiaguan Formation (Barremian–Albian) of Qijiang, South-Central China: New Discoveries, Ichnotaxonomy, Preservation and Palaeoecology. PLoS ONE. 10, e0141059., 10, Number 10: Public Library of Science Abstractlida_et_al_2015_an_ornithopod-dominated_tracksite_from_the.pdfWebsite

The historically-famous Lotus Fortress site, a deep 1.5–3.0-meter-high, 200-meter-long horizonal notch high up in near-vertical sandstone cliffs comprising the Cretaceous Jiaguan Formation, has been known since the 13th Century as an impregnable defensive position. The site is also extraordinary for having multiple tetrapod track-bearing levels, of which the lower two form the floor of part of the notch, and yield very well preserved asseamblages of ornithopod, bird (avian theropod) and pterosaur tracks. Trackway counts indicate that ornithopods dominate (69%) accounting for at least 165 trackmakers, followed by bird (18%), sauropod (10%), and pterosaur (3%). Previous studies designated Lotus Fortress as the type locality of Caririchnium lotus and Wupus agilis both of which are recognized here as valid ichnotaxa. On the basis of multiple parallel trackways both are interpreted as representing the trackways of gregarious species. C. lotus is redescribed here in detail and interpreted to indicate two age cohorts representing subadults that were sometimes bipedal and larger quadrupedal adults. Two other previously described dinosaurian ichnospecies, are here reinterpreted as underprints and considered nomina dubia. Like a growing number of significant tetrapod tracksites in China the Lotus Fortress site reveals new information about the composition of tetrapod faunas from formations in which the skeletal record is sparse. In particular, the site shows the relatively high abundance of Caririchium in a region where saurischian ichnofaunas are often dominant. It is also the only site known to have yielded Wupus agilis. In combination with information from other tracksites from the Jiaguan formation and other Cretaceous formations in the region, the track record is proving increasingly impotant as a major source of information on the vertebrate faunas of the region. The Lotus Fortress site has been developed as a spectacular, geologically-, paleontologically- and a culturally-significant destination within Qijiang National Geological Park.

Araújo, R., Polcyn M. J., Lindgren J., Jacobs L. L., Schulp A. S., Mateus O., Gonçalves O. A., & Morais M. - L. (2015).  New aristonectine elasmosaurid plesiosaur specimens from the Early Maastrichtian of Angola and comments on paedomorphism in plesiosaurs. Netherlands Journal of Geosciences. FirstView, 1–16., 2 Abstractaraujo_et_al_2015_paedomorphism-libre.pdfWebsite

ABSTRACT New elasmosaurid plesiosaur specimens are described from the Early Maastrichtian of Angola. Phylogenetic analyses reconstruct the Angolan taxon as an aristonectine elasmosaurid and the sister taxon of an unnamed form of similar age from New Zealand. Comparisons also indicate a close relationship with an unnamed form previously described from Patagonia. All of these specimens exhibit an ostensibly osteologically immature external morphology, but histological analysis of the Angolan material suggests an adult with paedomorphic traits. By extension, the similarity of the Angolan, New Zealand and Patagonian material indicates that these specimens represent a widespread paedomorphic yet unnamed taxon.