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2021
Marx, M. P., Mateus O., Polcyn M. J., Schulp A. S., Gonçalves O. A., & Jacobs L. L. (2021).  The cranial anatomy and relationships of Cardiocorax mukulu (Plesiosauria: Elasmosauridae) from Bentiaba, Angola. PLOS ONE. 16(8), e0255773 - ., 2021/08/17: Public Library of Science AbstractWebsite

We report a new specimen of the plesiosaur Cardiocorax mukulu that includes the most complete plesiosaur skull from sub-Saharan Africa. The well-preserved three-dimensional nature of the skull offers rare insight into the cranial anatomy of elasmosaurid plesiosaurians. The new specimen of Cardiocorax mukulu was recovered from Bentiaba, Namibe Province in Angola, approximately three meters above the holotype. The new specimen also includes an atlas-axis complex, seventeen postaxial cervical vertebrae, partial ribs, a femur, and limb elements. It is identified as Cardiocorax mukulu based on an apomorphy shared with the holotype where the cervical neural spine is approximately as long anteroposteriorly as the centrum and exhibits a sinusoidal anterior margin. The new specimen is nearly identical to the holotype and previously referred material in all other aspects. Cardiocorax mukulu is returned in an early-branching or intermediate position in Elasmosauridae in four out of the six of our phylogenetic analyses. Cardiocorax mukulu lacks the elongated cervical vertebrae that is characteristic of the extremely long-necked elasmosaurines, and the broad skull with and a high number of maxillary teeth (28–40) which is characteristic of Aristonectinae. Currently, the most parsimonious explanation concerning elasmosaurid evolutionary relationships, is that Cardiocorax mukulu represents an older lineage of elasmosaurids in the Maastrichtian.

Jackson, Y., Economos R., Jacobs L., Mateus O., & Gonçalves A. O. (2021).  When Dinosaurs Walked Through Diamonds: Constraining the Age of Early Cretaceous Footprints in Volcanic Crater Sediments. SMU Journal of Undergraduate Research. 6(1), : DOI: https://doi.org/ 10.25172/jour.6.1.1 Available at: https://scholar.smu … Abstractwhen_dinosaurs_walked_through_diamonds.pdf

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2020
Jacobs, L.  L., Sousa N., Goncalves A.  O., Mateus O., Polcyn M.  J., & Schulp A.  S. (2020).  Projecto PaleoAngola: Geoheritage and Conservation Paleobiology as Science for Development in Angola. AGU Fall Meeting Abstracts. 2020, SY048-05. Abstractprojecto_paleoangola__geoheritage.pdf

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Jackson, Y. J., Economos R. C., Jacobs L. L., Mateus O., & Gonçalves A. O. (2020).  When dinosaurs walked through diamonds: constraining the age of Early Cretaceous footprints in volcanic crater sediments. 54th Annual GSA South-Central Section Meeting 2020. , Fort Worth: Geological Society of America Abstracts with Programs. Vol. 52, No. 1jackson_et_al_2020_abstract__when_dinosaurs_walked_through_diamonds__gsa.pdf
2019
Schulp, A. S., Mateus O., Polcyn M., Gonçalves A., & Jacobs L. L. (2019).  Angola and its role in the paleobiogeography of Gondwana. Journal of Vertebrate Paleontology, Program and Abstracts. 188.schulp_et_al_2019_angola_svp_abstract.pdf
Mateus, O., Callapez P. M., Polcyn M. J., Schulp A. S., Gonçalves A. O., & Jacobs L. L. (2019).  The Fossil Record of Biodiversity in Angola Through Time: A Paleontological Perspective. (Huntley, Brian J., Russo, Vladimir, Lages, Fernanda, Ferrand, Nuno, Ed.).Biodiversity of Angola: Science & Conservation: A Modern Synthesis. 53–76.: Springer International Publishing Abstractmateus2019_chapter_thefossilrecordofbiodiversityi.pdf

This chapter provides an overview of the alpha paleobiodiversity of Angola based on the available fossil record that is limited to the sedimentary rocks, ranging in age from Precambrian to the present. The geological period with the highest paleobiodiversity in the Angolan fossil record is the Cretaceous, with more than 80{%} of the total known fossil taxa, especially marine molluscs, including ammonites as a majority among them. The vertebrates represent about 15{%} of the known fauna and about one tenth of them are species firstly described based on specimens from Angola.

Mateus, O., Callapez P. M., Polcyn M. J., Schulp A. S., Gonçalves A. O., & Jacobs L. L. (2019).  O registo fóssil da biodiversidade em Angola ao longo do tempo: uma perspectiva paleontológica. (Huntley B.J., Russo V., Lages F., Ferrand N., Ed.).Biodiversidade de Angola: Ciência e Conservação - Uma Síntese Moderna. 89-116., Porto: Arte & Ciência Abstractmateus_et_al_2019_paleobiodiversidade_angola.pdf

Este capítulo apresenta uma visão geral da paleobiodiversidade alfa de Angola com base no registo fóssil disponível, o qual se limita às rochas sedimentares, a sua idade variando entre o Pré‑Câmbrico e o pre‑
sente. O período geológico com a maior paleobiodiversidade no registo fóssil angolano é o Cretácico, com mais de 80% do total dos táxones fósseis conhecidos, especialmente moluscos marinhos, sendo estes na sua maioria
amonites. Os vertebrados representam cerca de 15% da fauna conhecida e cerca de um décimo destes são espécies descritas pela primeira vez com base em espécimes de Angola.

Schulp, A. S., Mateus O., Polcyn M., c}alves G. {\cA., & Jacobs L. L. (2019).  Angola and its role in the paleobiogeography of Gondwana. Journal of Vertebrate Paleontology, Program and Abstracts. 188. Abstract
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Mateus, O., Callapez P. M., Polcyn M. J., Schulp A. S., Gonçalves A. O., & Jacobs L. L. (2019).  The Fossil Record of Biodiversity in Angola Through Time: A Paleontological Perspective. (Huntley, Brian J., Russo, Vladimir, Lages, Fernanda, Ferrand, Nuno, Ed.).Biodiversity of Angola: Science {&} Conservation: A Modern Synthesis. 53–76., Cham: Springer International Publishing Abstract

This chapter provides an overview of the alpha paleobiodiversity of Angola based on the available fossil record that is limited to the sedimentary rocks, ranging in age from Precambrian to the present. The geological period with the highest paleobiodiversity in the Angolan fossil record is the Cretaceous, with more than 80{%} of the total known fossil taxa, especially marine molluscs, including ammonites as a majority among them. The vertebrates represent about 15{%} of the known fauna and about one tenth of them are species firstly described based on specimens from Angola.

2018
Myers, T. S., Polcyn M. J., Mateus O., Vineyard D. P., Gon?alves A. O., & Jacobs L. L. (2018).  A new durophagous stem cheloniid turtle from the lower Paleocene of Cabinda, Angola. Papers in Palaeontology. 4, 161-176., Number 2 Abstract
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2017
Mateus, O., Marzola M., Schulp A. S., Jacobs L. L., Polcyn M. J., Pervov V., Gonçalves A. O. {\'ı}mpio, & Morais M. L. (2017).  Angolan ichnosite in a diamond mine shows the presence of a large terrestrial mammaliamorph, a crocodylomorph, and sauropod dinosaurs in the Early Cretaceous of Africa. Palaeogeography, Palaeoclimatology, Palaeoecology. 471, 220–232., apr: Elsevier {BV} AbstractWebsite
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Mateus, O., Marzola M., Schulp A. S., Jacobs L. L., Polcyn M. J., Pervov V., Gonçalves A. O., & Morais M. L. (2017).  Angolan ichnosite in a diamond mine shows the presence of a large terrestrial mammaliamorph, a crocodylomorph, and sauropod dinosaurs in the Early Cretaceous of Africa. Palaeogeography, Palaeoclimatology, Palaeoecology. 471, 220 - 232. Abstractmateus_et_al_2017_angolan_ichnosite_catoca.pdfWebsite

Abstract We report here new and the first mammaliamorph tracks from the Early Cretaceous of Africa. The tracksite, that also bears crocodylomorph and sauropod dinosaurian tracks, is in the Catoca diamond mine, Lunda Sul Province, Angola. The mammaliamorph tracks have a unique morphology, attributed to Catocapes angolanus ichnogen. et ichnosp. nov. and present an anterolateral projection of digit I and V. The tracks with an average length of 2.7 cm and width of 3.2 cm are the largest mammaliamorph tracks known from the Early Cretaceous unmatched in size in the skeletal fossil record. The crocodylomorph trackways and tracks are attributed to Angolaichnus adamanticus ichnogen. et ichnosp. nov. (‘ichnofamily’ Batrachopodidae) and present a functionally pentadactyl pes, an extremely outwardly rotated handprint, and an unusual tetradactyl and plantigrade manus. One medium-sized sauropod dinosaur trackway preserved skin impressions of a trackmaker with stride length of 1.6 m; a second is that of a small-sized sauropod trackmaker with a pace length of 75 cm.

Myers, T. S., Polcyn M. J., Mateus O., Vineyard D. P., Gonçalves A. O., & Jacobs L. L. (2017).  A new durophagous stem cheloniid turtle from the lower Paleocene of Cabinda, Angola. Papers in Palaeontology. 2017, 1-16. Abstractnew_durophagous_stem_cheloniid_turtle_from_the_lower_paleocene_of_cabinda_angola.pdfWebsite

A new stem cheloniid turtle, Cabindachelys landanensis, gen. et sp. nov., is represented by a nearly complete skull and partial hyoid collected in lower Paleocene shallow marine deposits, equivalent to the offshore Landana Formation, near the town of Landana in Cabinda, Angola. A partial chelonioid carapace previously reported from this locality is referred here to C. landanensis. Cabindachelys landanensis possesses clear synapomorphies of Pan-Cheloniidae, including a rod-like rostrum basisphenoidale, V-shaped basisphenoid crest, and secondary palate, but also retains a reduced foramen palatinum posterius, unlike most other pan-cheloniids. Phylogenetic analysis suggests that C. landanensis forms a weakly-supported clade with Erquelinnesia gosseleti, Euclastes acutirostris, Euclastes wielandi and Terlinguachelys fischbecki, although a close relationship between the protostegid T. fischbecki and these durophagous pan-cheloniids is unlikely. The Paleocene–Eocene strata near Landana have produced a number of turtle fossils, including the holotype specimen of the pleurodire Taphrosphys congolensis. A turtle humerus collected c. 1 m above the holotype skull of C. landanensis differs from humeri of chelonioids and Taphrosphys, indicating that a third turtle taxon is present at Landana. Cheloniid fossil material is rare in the Landana assemblage, in comparison with the abundant remains of Taphrosphys congolensis found throughout the stratigraphic section. This disparity implies that C. landanensis preferred open marine habitats, whereas Taphrosphys congolensis spent more time in nearshore environments. The appearance of new durophagous species such as C. landanensis in the early Paleocene reflects the rapid radiation of pan-cheloniids as they diversified into open niches following the K–Pg extinction.

2016
Ceríaco, L. M. P., Gutiérrez E. E., Dubois A., Abdala C. S., Alqarni A. S., Adler K., et al. (2016).  Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences. Zootaxa. 4196(3), 435 - 445., 2016 AbstractWebsite
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Polcyn, M. J., Bardet N., Amaghzaz M., Gonçalves O. A., Jourani E., Kaddumi H. F., Lindgren J., Mateus O., Meslouhf S., Morais M. L., Pereda-Suberbiola X., Schulp A. S., Vincent P., & Jacobs L. L. (2016).  An extremely derived plioplatecarpine mosasaur from the Maastrichtian of Africa and the Middle East. 5th Triennial Mosasaur Meeting- a global perspective on Mesozoic marine amniotes. 16-20(May 16-20, 2016), May 16-20, 2016., Uppsala, Sweden: Museum of Evolutiom, Uppsala University. Abstractpolcyn_et_al_2016_extremely_derived_mosasaur.pdf

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Myers, T. S., Mateus O., Polcyn M. J., Vineyard D., & Jacobs L. L. (2016).  A new chelonioid turtle from the Paleocene of Cabinda, Angola. Annual Meeting of the Society of Vertebrate Paleontology. 194.: Journal of Vertebrate Paleontology, Program and Abstracts, 2016 Abstractmyers_etal_2016_chelonoid_angola_turtle_svp_abstract.pdf

We report a new chelonioid turtle on the basis of a nearly complete skull collected in lower Paleocene, shallow marine deposits, equivalent to the offshore Landana Formation, near the town of Landana in Cabinda Province, Angola. Chelonioid material previously reported from this locality is likely referable to this new taxon. The well-preserved skull is missing the left quadrate, squamosal, and prootic, both opisthotics, and the mandible. The skull possesses a rod-like basisphenoid rostrum, which is a synapomorphy of Chelonioidea, but it differs from other chelonioid skulls in that the contact between the parietal and squamosal is absent, and the posterior palatine foramen is present. Phylogenetic analysis recovers the new taxon as a basal chelonioid. The Paleocene– Eocene strata near Landana have produced a wealth of turtle fossils, including the holotype of the pleurodire Taphrosphys congolensis. A turtle humerus collected from the Landana locality differs morphologically from the humeri of chelonioids and Taphrosphys, indicating the presence of a third taxon. Chelonioid fossil material in the Landana assemblage is rare compared to the abundant fragmentary remains of Taphrosphys that are found throughout the stratigraphic section. This disparity in abundance suggests the new chelonioid taxon preferred open marine habitats, whereas Taphrosphys frequented nearshore environments.

Jacobs, L. L., Polcyn M. J., Mateus O., Schulp A. S., Gonçalves A. O., & Morais M. L. (2016).  Post-Gondwana Africa and the vertebrate history of the Angolan Atlantic Coast. Memoirs of Museum Victoria. 74, 343–362. Abstractjacobs_et_al_2016_post-gondwana_africa_and_the_vertebrate_history_of_the_angolan_atlantic_coast_343-362_mmv74_jacobs_4_web.pdf

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Polcyn, M. J., Bardet N., Amaghzaz M., Gon{\c c}alves O. A., Jourani E., Kaddumi H. F., Lindgren J., Mateus O., Meslouhf S., Morais M. L., Pereda-Suberbiola X., Schulp A. S., Vincent P., & Jacobs L. L. (2016).  An extremely derived plioplatecarpine mosasaur from the Maastrichtian of Africa and the Middle East. 5th Triennial Mosasaur Meeting- a global perspective on Mesozoic marine amniotes. 16-20, May 16-20, 2016., Uppsala, Sweden: Museum of Evolutiom, Uppsala University. Abstract

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Polcyn, M. J., Bardet N., Amaghzaz M., Gon\{\c c\}alves O. A., Jourani E., Kaddumi H. F., Lindgren J., Mateus O., Meslouhf S., Morais M. L., Pereda-Suberbiola X., Schulp A. S., Vincent P., & Jacobs L. L. (2016).  An extremely derived plioplatecarpine mosasaur from the Maastrichtian of Africa and the Middle East. 5th Triennial Mosasaur Meeting- a global perspective on Mesozoic marine amniotes. 16-20, May 16-20, 2016., Uppsala, Sweden Abstract
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Polcyn, {M. J. }, Bardet N., Amaghzaz M., Gonçalves {A. O. }, Jourani E., Kaddumi {H. F. }, Lindgren J., Mateus O., Meslouhf S., & Morais {M. L. } (2016).  An extremely derived plioplatecarpine mosasaur from the Maastrichtian of Africa and the Middle East. 32–33. Abstract
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Myers, T. S., Mateus O., Polcyn M. J., Vineyard D., & Jacobs L. L. (2016).  A new chelonioid turtle from the Paleocene of Cabinda, Angola. Journal of Vertebrate Paleontology, Program and Abstracts, 2016, p. 194.. 194. Abstract

We report a new chelonioid turtle on the basis of a nearly complete skull collected in lower Paleocene, shallow marine deposits, equivalent to the offshore Landana Formation, near the town of Landana in Cabinda Province, Angola. Chelonioid material previously reported from this locality is likely referable to this new taxon. The well-preserved skull is missing the left quadrate, squamosal, and prootic, both opisthotics, and the mandible. The skull possesses a rod-like basisphenoid rostrum, which is a synapomorphy of Chelonioidea, but it differs from other chelonioid skulls in that the contact between the parietal and squamosal is absent, and the posterior palatine foramen is present. Phylogenetic analysis recovers the new taxon as a basal chelonioid. The Paleocene– Eocene strata near Landana have produced a wealth of turtle fossils, including the holotype of the pleurodire Taphrosphys congolensis. A turtle humerus collected from the Landana locality differs morphologically from the humeri of chelonioids and Taphrosphys, indicating the presence of a third taxon. Chelonioid fossil material in the Landana assemblage is rare compared to the abundant fragmentary remains of Taphrosphys that are found throughout the stratigraphic section. This disparity in abundance suggests the new chelonioid taxon preferred open marine habitats, whereas Taphrosphys frequented nearshore environments.

Myers, T. S., Mateus O., Polcyn M. J., Vineyard D., & Jacobs L. L. (2016).  A new chelonioid turtle from the Paleocene of Cabinda, Angola. Journal of Vertebrate Paleontology, Program and Abstracts, 2016, p. 194.. 194. Abstract
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Myers, T. S., Mateus O., Polcyn {M. J. }, Vineyard D., & Jacobs L. L. (2016).  A new chelonioid turtle from the Paleocene of Cabinda, Angola. Abstract

We report a new chelonioid turtle on the basis of a nearly complete skull collected in lower Paleocene, shallow marine deposits, equivalent to the offshore Landana Formation, near the town of Landana in Cabinda Province, Angola. Chelonioid material previously reported from this locality is likely referable to this new taxon. The well-preserved skull is missing the left quadrate, squamosal, and prootic, both opisthotics, and the mandible. The skull possesses a rod-like basisphenoid rostrum, which is a synapomorphy of Chelonioidea, but it differs from other chelonioid skulls in that the contact between the parietal and squamosal is absent, and the posterior palatine foramen is present. Phylogenetic analysis recovers the new taxon as a basal chelonioid. The Paleocenetextendash Eocene strata near Landana have produced a wealth of turtle fossils, including the holotype of the pleurodire Taphrosphys congolensis. A turtle humerus collected from the Landana locality differs morphologically from the humeri of chelonioids and Taphrosphys, indicating the presence of a third taxon. Chelonioid fossil material in the Landana assemblage is rare compared to the abundant fragmentary remains of Taphrosphys that are found throughout the stratigraphic section. This disparity in abundance suggests the new chelonioid taxon preferred open marine habitats, whereas Taphrosphys frequented nearshore environments.

Ceríaco, L. M. P., Gutiérrez E. E., Dubois A., Abdala C. S., Alqarni A. S., Adler K., et al. (2016).  Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences. Zootaxa. 4196, 435-445., Number 3 Abstract
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Jacobs, L. L., Polcyn M. J., Mateus O., Schulp A. S., Gon?alves A. O., & Morais M. L. (2016).  Post-Gondwana Africa and the vertebrate history of the Angolan Atlantic Coast. Memoirs of Museum Victoria. 74, 343-362. Abstract
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Jacobs, L. L., Polcyn M. J., Mateus O. \á\}vio, Schulp A. S., Gon\{\c c\}alves A. \ó\}nio O., & Morais M. L. (2016).  Post-Gondwana Africa and the vertebrate history of the Angolan Atlantic Coast. Memoirs of Museum Victoria. 74, 343\–\}362. Abstract
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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. , July 2015, Opole, Poland: European Association of Vertebrate Palaeontologistsmarzola_et_al_2015_catoca_tracks_eavp.pdf
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. , July 2015, Opole, Poland: European Association of Vertebrate Palaeontologists Abstract
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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.

Strganac, C., Jacobs L. L., Polcyn M. J., Ferguson K. M., Mateus O., Gonçalves O. A., Morais M. - L., & da Silva Tavares T. (2015).  Stable oxygen isotope chemostratigraphy and paleotemperature regime of mosasaurs at Bentiaba, Angola. Netherlands Journal of Geosciences. FirstView, 1–7., 2 Abstractstrganac_etal2015_stable_oxigen_isotopes.pdfWebsite

ABSTRACT Stable oxygen isotope values of inoceramid marine bivalve shells recovered from Bentiaba, Angola, are utilised as a proxy for paleotemperatures during the Late Cretaceous development of the African margin of the South Atlantic Ocean. The δ18O values derived from inoceramids show a long-term increase from –3.2‰ in the Late Turonian to values between –0.8 and –1.8‰ in the Late Campanian. Assuming a constant oceanic δ18O value, an ∼2‰ increase may reflect cooling of the shallow marine environment at Bentiaba by approximately 10°. Bentiaba values are offset by about +1‰ from published records for bathyal Inoceramus at Walvis Ridge. This offset in δ18O values suggests a temperature difference of ∼5° between coastal and deeper water offshore Angola. Cooler temperatures implied by the δ18O curve at Bentiaba coincide with the stratigraphic distribution of diverse marine amniotes, including mosasaurs, at Bentiaba.

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.

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.

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.

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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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.

2014
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
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.

Tschopp, E., Mateus O., Kosma R., Sander M., Joger U., & Wings O. (2014).  A specimen-level cladistic analysis of Camarasaurus (Dinosauria, Sauropoda) and a revision of camarasaurid taxonomy. Journal of Vertebrate Paleontology. Program and Abstracts, 2014, 241-242.tschopp_et_al._2014_a_specimen-level_cladistic_analysis_of_camarasaurus.pdf
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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