Angola - Africa

PaleoAngola

The Department of Earth Sciences of FCT NOVA has a collaboration in the area of Vertebrate Paleontology with Angola since 2005 through the Projecto PaleoAngola www.paleoangola.com, represented by Prof. Octávio Mateus.

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.

Polcyn, M. J., Jacobs L. L., Schulp A. S., & Mateus O. (2007).  Morphology and systematic position of Angolasaurus bocagei and the evolution of the braincase in Plioplatecarpine mosasaurs. Second Mosasaur Meeting. , May 3-6, 2007, Sternberg Museum, Hays, Kansaspolcyn_et_al_2007_angolosaurus_mosasaurmeetingabstracts.pdf
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., 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., 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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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
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
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.