Angola - Africa

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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.

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., Jacobs L., Polcyn M., Mateus O., & Schulp A. (2010).  Plesiosaurs from the Maastrichtian of Bentiaba, Namibe Province, Angola. Society of Vertebrate Paleontology 70th Annual Meeting.. Abstractaraujo_polcyn_mateus__schulp_2010_plesiosaurs_from_maastrichtian_of_angola_svp10abstracts.pdf

Recent excavations at the Maastrichtian locality of Bentiaba, Namibe Province, in the southern part of Angola, have yielded high quality and partially articulated plesiosaur specimens that indicate at least three taxa were present. A new elasmosaurid is the most abundant and well-preserved plesiosaur taxon at Bentiaba. It is known from a complete articulated paddle and other elements of the skeleton, many of which remain to be collected. The most diagnostic elements so far recovered are the complete pelvic and pectoral girdles, which indicate that the Bentiaba elasmosaurid is probably a new genus because it bears an asymmetrical ventral process of the coracoids, a complete cordiform posterior coracoid vacuity, and pronounced excavation of the anterior border of the coracoids, among other characters. A polycotylid is [...]

Jacobs, L. L., Polcyn M. J., Mateus O., Schulp A., Ferguson K., Scotese C., Jacobs B. F., Strganac C., Vineyard D., Myers T. S., & Morais M. L. (2010).  Tectonic Drift, Climate, and Paleoenvironment of Angola Since the Cretaceous. AGU Fall Meeting Abstracts, 1:. 02., Jan Abstractjacobs_polcyn_mateus_et_al_2010_tectonic_drift_climate_and_paleoenvironment_of_angola_since_the_cretaceous.pdf

Africa is the only continent that now straddles arid zones located beneath the descending limbs of both the northern and southern Hadley cells, and it has done so since it became a distinct continent in the Early Cretaceous. Since that time, Africa has drifted tectonically some 12 degrees north and rotated approximately 45 degrees counterclockwise. This changing latitudinal setting and position of the landmass under the relatively stable Hadley Cells is manifested as southward migration of climatic zones over the past 132 million years. Data from kerogen, X-ray diffraction analysis of sedimentary matrix, carbon isotopes from shell samples and tooth enamel,new 40Ar/39Ar radiometric dates, pollen and plant macrofossils, and fossil vertebrates indicate a productive upwelling system adjacent to a coastal desert since the opening of the South Atlantic Ocean; however, the position of the coastal desert has migrated southward as Africa drifted north, resulting in today's Skeleton Coast and Benguela Current. This migration has had a profound effect on the placement of the West African coast relative to areas of high marine productivity and resulting extensive hydrocarbon deposits, on the placement of arid zones relative to the continent especially the Skeleton Coast desert, on the climatic history of the Congo Basin (which shows a Late Cretaceous decrease in aridity based on the relative abundance of analcime in the Samba core), and in reducing the southern temperate region of Africa from 17% of continental area during the Cretaceous to 2% today. We show here that these related geographic and environmental changes drove ecological and evolutionary adjustments in southern African floras and faunas, specifically with respect to the distribution of anthropoid primates, the occurrence of modern relicts such as the gnetalean Welwitschia mirabilis, endemism as in the case of ice plants, and mammalian adaption to an open environment as in springhares. Africa's tectonic drift through climate zones has been a first-order environmental determinant since the Early Cretaceous.

Jacobs, L., Polcyn M., Araújo R., Strganac C., & Mateus O. (2010).  Physical drivers of evolution and the history of the marine tetrapod fauna of Angola. Annual Meeting of the Society of Vertebrate Paleontology. 110A., Jan Abstractjacobs_et_al_mateus_2010_physical_drivers_marine_tetrapod_fauna_of_angola_svp10abstracts.pdf


Jacobs, L., Polcyn M., Mateus O., Schulp A. S., & Neto A. B. (2009).  The Cretaceous Skeleton Coast of Angola. Journal of Vertebrate Paleontology. 29, 121A., Jan Abstractjacobs_et_al_2009cretaceousskeletoncoas.pdfWebsite


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.

Vineyard, D. P., Jacobs L. L., Polcyn M. J., Mateus O., Schulp A. S., & Strganac C. (2009).  Euclastes from the Maastrichtian of Angola and the distribution of the Angolachelonia. Eugene Gaffney Turtle Symposium. , Royal Tyrrell Museum
Schulp, A. S., Polcyn M. J., Mateus O., Jacobs L. L., & Morais M. L. (2008).  A new species of Prognathodon (Squamata, Mosasauridae) from the Maastrichtian of Angola, and the affinities of the mosasaur genus Liodon. Proceedings of the Second Mosasaur Meeting, Fort Hays Studies Special Issue 3, Fort Hays State University, Hays, Kansas. 1-12. Abstractschulp_et_al_2008_prognathodon_kianda.pdf

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