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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.

Vertebrate-bearing fossiliferous outcrops of Cretaceous age in sub-Saharan Africa are rare because of younger superficial deposits, vegetation cover, and the widespread occurrence of Precambrian metamorphic plateau basement comprising much of the continent. However, one area of extensive marine and nonmarine
Cretaceous exposures is found between the plateau and the coast in Angola. The Angolan margin was formed in conjunction with the breakup of Gondwana and subsequent growth of the South Atlantic. Cretaceous deposits are constrained in age by the emplacement of oceanic crust, which began no later than magnetozone M3
(approximately 128 Ma, Barremian). Shallow marine facies are exposed in sea cliffs but equivalent facies become increasingly terrestrial inland. Few vertebrate fossils have been described from Angola aside from sharks.
Notable exceptions are the late Turonian mosasaurs Angolasaurus bocagei and Tylosaurus iembeensis from northern Angola. Those taxa are significant because they are among the earliest derived mosasaurs. Recent field work led to the discovery of a new skull of Angolasaursus as well as sharks, fish, plesiosaurs, the skull of a new taxon of turtle, additional mosasaurs, and the articulated forelimb of a sauropod dinosaur, the first reported dinosaur from Angola. In southern Angola, marine sediments spanning the Cretaceous-Paleogene boundary are found.

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.

Found in the Upper Jurassic outcrops of Lourinhã, Portugal, and first published in 1997, the Paimogo dinosaur egg clutch is one of Portugal’s most remarkable fossils, with over one hundred eggs preserved in association with embryonic bones, of the allosauroid theropod Lourinhanosaurus. However, many questions about it have remained unanswered, even until the present day. After its discovery, this extraordinary fossil became the keystone of a small local museum, greatly kick-starting regional tourism, while also holding the fossils in trust for future generations to study. More than 20 years later, continually sustained paleontological interest from the public has even given rise to both a highly successful dinosaur theme park in the region and an aspiring UNESCO Geopark. Recently, a multidisciplinary team of preparators, paleontologists, sedimentologists, mineralogists, and geochemists revisited an unopened jacket from the original excavation using an array of techniques to address various questions. Studies are ongoing, but the corpus of information obtained and the methodologies utilized to gather data have offered an opportunity to design an exhibit around the history of the Paimogo clutch, highlighting the scientific methods involved, and asserting the importance of preserving geological heritage for the future, when new tools will doubtlessly become available to provide yet another new look at old fossils. Here, we describe our analytical procedures and present an innovative exhibit designed to introduce to the public the latest advances on the research behind an iconic piece of Portuguese geoheritage, increasing its value both as a research item and as an educational resource.

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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.

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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 [...]

A large, well-preserved vertebrate coprolite was found in a lacustrine sediment in the Malmros Klint Formation of the Late Triassic Fleming Fjord Group in the Jameson Land Basin, central East Greenland. The size and internal and external morphology of the coprolite is consistent with that of crocodilian coprolites and one end of the coprolite exhibits evidence of post-egestion trampling. As the associated vertebrate fauna of the Fleming Fjord Group contains abundant remains of pseudosuchian phytosaurs, the coprolite is interpreted as being from a large phytosaur.

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We present a stratigraphic log supporting a preliminary magnetostratigraphy of a Tithonian–Berriasian section in Porto da Calada (Portugal). Based on biostratigraphy and reversed and normal magnetostratigraphy, the location of the Tithonian–Berriasian boundary is tentatively located at ca. 52 m, not in disagreement
with former proposals. Due to the occurrence of later remagnetization (diagenesis), the magnetostratigraphic definition of the Tithonian–Berriasian section at the Cabo Espichel (Portugal) location was not able to be established.

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Here, we describe the first pterosaur remains from Angola, an assemblage of fourteen bones from the Lower Maastrichtian marine deposits of Bentiaba, Namibe Province. One new species is introduced, Epapatelo otyikokolo, gen. et sp. nov., which comprises an articulated partial left humerus and ulna as well as an articulated left ulna and radius (from a second individual). Phylogenetic analysis confirms a non-nyctosaurid pteranodontian attribution for this new taxon and supports a new apomorphy-based clade, Aponyctosauria, which is here defined. Late Cretaceous pteranodontians are rare in Sub-Saharan Africa and throughout the Southern Hemisphere. Preliminary histological analysis also reveals a likely sub-adult age for one of the specimens. This fossil assemblage provides a first glimpse of Angolan pterosaur paleobiodiversity providing further insight into the Gondwanan ecosystems of the Upper Cretaceous.

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O sítio de Silveirinha é uma das localidades de mamíferos mais conhecidas da Paleontologia do Cenozoico de Portugal e da Europa em geral. Graças à sua rica e diversificada associação de mamíferos, com mais de 30 taxa, foi posicionado no Eocénico inferior (início do Ypresiano, MP7, ca. 55,8 M.a.), sendo o local mais antigo da Europa desta Época, devido à presença única de taxa típicos do Paleocénico superior, juntamente com outras espécies já características do Eocénico inferior. Este estudo irá rever o material de pequenos mamíferos deste sítio, conservado na coleção clássica da Universidade Nova de Lisboa, a fim de fazer uma actualização taxonómica à luz das publicações mais recentes.

Ostriches are known to be the fastest bipedal animal alive; to accomplish such an achievement, their anatomy evolved to sustain the stresses imposed by running at such velocities. Ostriches represent an excellent case study due to the fact that their locomotor kinematics have been extensively studied for their running capabilities. The shape and structure of ostrich bones are also known to be optimized to sustain the stresses imposed by the body mass and accelerations to which the bones are subjected during movements. This study focuses on the limb bones, investigating the structure of the bones as well as the material properties, and how both the structure and material evolved to maximise the performance while minimising the stresses applied to the bones themselves. The femoral shaft is hollowed and it presents an imbricate structure of fused bone ridges connected to the walls of the marrow cavity, while the tibial shaft is subdivided into regions having different mechanical characteristics. These adaptations indicate the optimization of both the structure and the material to bear the stresses. The regionalization of the material highlighted by the mechanical tests represents the capability of the bone to adapt to external stimuli during the life of an individual, optimizing not only the structure of the bone but the material itself.

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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.

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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.

The Late Triassic (ca. 237-201.5 million years ago) was a transitional interval in the evolution of terrestrial ecosystems, during which ‘modern’ clades such as archosaurs and mammals were radiating while ‘archaic’ groups such as temnospondyl amphibians and basal synapsids remained abundant. Little is known about the Triassic terrestrial (nonmarine) vertebrates of the Iberian Peninsula. The Algarve Basin of southern Portugal is an extensional rift basin formed during the breakup of Pangaea, which is filled with terrestrial, lacustrine, and marginal marine siliciclastics of the Grés de Silves Formation, interbedded with CAMP basalts that mark the end-Triassic extinction (radioisotopically dated to ~198-201.5 Ma). Since 2009, our field project in the Algarve has discovered numerous vertebrate specimens within the Grés de Silves, including a monodominant bonebed containing hundreds of specimens of metoposaurids, a peculiar group of temnospondyls that filled crocodile-like predatory niches in lacustrine and fluvial environments. These specimens appear to belong to a new species of Metoposaurus, similar to M. diagnosticus and M. krasiejowensis from central Europe but possessing several putative autapomorphies of the braincase and lower jaw. We also discovered a mandible of a phytosaur, the first specimen of these long-snouted, semi-aquatic archosauriforms from the Iberian Peninsula. These discoveries of characteristic Carnian Norian taxa indicate that the fossil-bearing portion of the Grés de Silves is Late Triassic in age, and provide further evidence that metoposaurids and phytosaurs commonly occurred together in low palaeolatitudes during this time.