Recent fieldwork in the Namibe province in southern Angola yielded cranial and postcranial elements of at least two individuals of the rare and enigmatic mosasaur Halisaurus from a single small excavation. The genus Halisaurus is unique in retaining a primitive configuration of the temporal arcade, specifically a broad, vertically oriented contact between the parietal and the supratemporal. The supratemporal is broadly sutured to the opisthotic and prootic, unlike the condition in varanoids in which the simple lunate element lies between the parietal ramus and the squamosal and does not form a sutural contact with the opisthotic or prootic, but as in other halisaurines retains a plesiomorphic, vertically oriented contact with the parietal rami. The squamosal is lightly built and broadly arched as in Varanus. Comparison with known halisaurines indicates the new material is referable to the species Halisaurus arambourgi.
The locality that yielded the new specimens has also yielded a large number of isolated teeth, bones, articulated, and associated skeletons of Mosasaurus, Prognathodon, Globidens, and Plioplatecarpus, which with Halisaurus comprise a mosasaur assemblage most similar to that reported from the Maastrichtian of Morocco.

The record of ornithischian dinosaurs from Portugal is substantial but incomplete in terms of our understanding of taxonomic composition and details of the anatomy of many forms. New data and reinterpretation of these forms are provided. The basal thyreophoran from the Lower Jurassic (the nomen dubium “Lusitanosaurus liasicus”) is the most primitive dinosaur from Iberia. Concerning the Late Jurassic, new material from the Lourinhã Formation (Kimmeridgian/Tithonian) referable to the stegosaur Dacentrurus provides additional information on the systematic position and osteology.
The new material shows two rows of paired triangular plates, with a notch in the anterior rim. A maxillary of an ankylosaur from the Vale Frades (Lourinhã Fm.) is here reported, but cannot be referable to Dracopelta, the only ankylosaur genus currently known from Portugal. The ornithopod Alocodon kuehnei reported as Middle Jurassic (Callovian) is probably Oxfordian in age. A right dentary (ML768 from Zimbral) from the Lourinhã Formation, Kimmeridgian/Tithonian, and shares affinities with Dryosaurus but possesses more denticulation and no secondary ridges, suggesting the occurrence of a new or unreported species for the Late Jurassic of Portugal, which is here tentatively ascribed to aff. Dryosaurus sp. In summary, the Late Jurassic ornithischians species/genera from Portugal include Dacentrurus armatus, Stegosaurus cf. ungulatus, Dracopelta zbyszewskii, Phyllodon henkeli, Hypsilophodon sp., Alocodon kuehnei, Trimucrodon cuneatus, aff. Dryosaurus and Draconyx loureiroi. The Lower Cretaceous (Hauterivian / Barremian) of Praia das Aguncheiras, in Cabo Espichel, provided a partial left maxillary (CPGP.1.99.7) of a basal iguanodontian that shows affinities with Camptosaurus, and is tentatively assigned to this genus. The maxillary teeth denticles differ from Iguanodon or other Iguanodontoidea because not show mammillations. More material is necessary to validate but, to be true, that would confirm the presence of this genus in the lower Cretaceous. The Iguanodon has been well reported in the Lower Cretaceous of Cabo Espichel.

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Although occurrences of marine reptiles have been previously reported from Angola, with the exception of two Turonian taxa, these reports were based largely on isolated teeth. Fieldwork in 2005 and 2006 yielded well-preserved remains of marine reptiles including plesiosaurs, turtles, and mosasaurs. The mosasaurs discussed here were recovered from two field areas: Turonian sediments at Iembe along the north coast and Maastrichtian sediments at Bentiaba on the south coast. The Turonian section near Iembe produced at least two new specimens of Angolasaurus bocagei and one fragmentary specimen of Tylosaurus iembeensis. One of the Angolasaurus specimens is represented by a well preserved, complete and articulated skull and partial postcrania, including portions of the forelimbs and pectoral girdle. The preservation of material from the Bentiaba locality is remarkable due to the grain support of the entombing sandstone, which preserves fine anatomical details with little apparent crushing, and in the number of articulated, semi-articulated, and associated skeletons. Identifications from the field and preliminary preparation show the Bentiaba mosasaur fauna is represented by at least five genera including Mosasaurus, Prognathodon, Globidens, Plioplatecarpus and Halisaurus. Collectively, these new specimens greatly expand our knowledge of the anatomy and systematics of Angolan mosasaurs.

Sauropod dinosaurs were the largest animals ever to inhabit the land, with truly gigantic forms in at least three lineages1, 2, 3. Small species with an adult body mass less than five tonnes are very rare4, 5, and small sauropod bones generally represent juveniles. Here we describe a new diminutive species of basal macronarian sauropod, Europasaurus holgeri gen. et sp. nov., and on the basis of bone histology we show it to have been a dwarf species. The fossils, including excellent skull material, come from Kimmeridgian marine beds of northern Germany6, 7, and record more than 11 individuals of sauropods 1.7 to 6.2 m in total body length. Morphological overlap between partial skeletons and isolated bones links all material to the same new taxon. Cortical histology of femora and tibiae indicates that size differences within the specimens are due to different ontogenetic stages, from juveniles to fully grown individuals. The little dinosaurs must have lived on one of the large islands around the Lower Saxony basin8. Comparison with the long-bone histology of large-bodied sauropods suggests that the island dwarf species evolved through a decrease in growth rate from its larger ancestor.

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Late Jurassic theropod dinosaurs have been known in Portugal since 1863 but only now are they being fully understood, with the recognition of genera such as Allosaurus, Aviatyrannis, Ceratosaurus, Lourinhanosaurus, and Torvosaurus from the Lourinhã and Alcobaça Formations (Kimmeridgian/Tithonian). Ceratosaurus dentisulcatus can now be reported from Portugal. It represents the only occurrence of this species outside the Morrison Formation.
New cranial elements confirm the presence of Torvosaurus tanneri, in Portugal. Torvosaurus was the largest Late Jurassic land carnivore. New postcranial and cranial elements allow the erection of a new species from Portugal, Allosaurus europaeus n.sp. The theropod assemblage of Portugal is similar to that of the Morrison Formation.

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.

The study of different kinds of morphological left-right (L-R) asymmetries in all taxa is a very powerful tool to understand evolution since it is a way to measure the developmentalstability of an organism against environmental perturbations. Excluding every pathologic or subtle asymmetry and all cases of taphonomic distortion, this work focuses only on two
kinds of unambiguous asymmetries: fluctuating and adaptative asymmetry. There are several cases of conspicuous left-right asymmetry in dinosaurs and is probably more common than previously thought. The pneumatic cavities systems in skull and vertebrae of theropodsand sauropods are the most common cases reported. The shape (but not the occurrence) of pneumatic cavities might have been exposed to weak selective pressure becoming more random than other body structures. Asymmetries are rarer in the appendicular bones possibly because it represents a strong handicap in the function of the limbs, consequently in the locomotion of the individual. Teeth counting show many exceptions to the typical L-R symmetry. Peculiar cases of adaptive asymmetry are related with the plates of stegosaurs and the ear displacement in the skull of the troodontids, which may have an important role in the physiology and ecology of the animals. The asymmetric displacement maximizes the surface exposure of the stegosaurs dorsal plates. This is an advantage, either the plates were used for thermoregulation, display or specific identification. Work in progress on the braincases of some troodontids specimens shows asymmetric ear openings, which suggests thatcan be an analogy resulting from convergent evolution between troodontids and strigiformes birds, used for 3D directional acoustics. Asymmetries are more common in animals that develop under stress. Animals that lived under dramatic environmental changes periods—like mass-extinctions episodes are believed to be—should present more asymmetries.
However, much more sampling and time accuracy is required in order to be able to relate dinosaur asymmetries to extinction episodes. Asymmetries show strong intra-individual variation and should be taken in consideration in taxonomical studies.

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