Robert Bussert

A new Theacean wood from the Cretaceous of northern Sudan

Abstract A new Theacean wood, Sladenioxylon africanum gen. et sp. nov., is described from a presumably Albian-Cenomanian fluviatile sequence of northern Sudan. This silicified structure is compared with the wood of the extant evergreen tropical tree Sladenia celastrifolia Kurz from China. It is probably among the earliest angiospermous wood remains known from northern Gondwana.

Turtle remains from the Wadi Milk Formation (Upper Cretaceous) of Northern Sudan

We describe here turtle remains from lag-type concentrations in channels and scours in the Wadi Milk Formation (Upper Cretaceous) of the Wadi Abu Hashim region in northern Sudan. Due to the isolated nature of the finds and the lack of any diagnostic material, such as skulls or more complete shell fragments, low-level taxonomic assignment was not possible. However, the morphology as well as the superficial ornamentation of most plates indicates pelomedusoid (Pleurodira) affinities, which is consistent with the geographically isolated nature of continental Africa during much of the Upper Cretaceous. The fauna contains one or two smaller sized pelomedusoid taxa as well as at least two large forms that are identified as members of Bothremydidae. A few plates may indicate the presence of other turtle lineages. Bothremydidae are known to have inhabited a variety of fluviatile and marine–littoral/near-coastal environments and thus are poor palaeoenvironmental indicators. However, bone compactness of one of the four peripheral morphotypes indicates the presence of a taxon that was more aquatic than typical Bothremydidae. Many plates show bioerosional traces that are interpreted as bore holes of clionid sponges, indicating a connection to a coastal environment exposed to marine influences. A marine or tidal influence is additionally suggested by sedimentological indicators, such as inclined heterolithic stratification, very variable palaeocurrent directions and partly intense bioturbation.

First record of Hyposaurus (Dyrosauridae, Crocodyliformes) from the Upper Cretaceous Shendi Formation of Sudan

ABSTRACT We describe a new record of the dyrosaurid crocodyliform genus Hyposaurus, from the ?Campanian— Maastrichtian Shendi Formation of Sudan, based on a partial mandibular symphysis, two posterior portions of the upper jaw, and a fused frontal bone, all belonging to a single individual. The material can be assigned to Hyposaurus on the basis of the elliptical shape of the mandibular symphysis (wider than high) and the overall flat shape of the mandible. At the same time, the fossil material differs from other species of Hyposaurus in having (1) an enlarged eighth alveolus of the dentary relative to the other alveoli; (2) a reduced interalveolar space between the ninth and tenth alveoli; and (3) a prominent ridge and groove sculpturing on the dorsal side of the mandible along the symphyseal region. However, due to the fragmentary nature of the material, we refrain from drawing any higher-resolution taxonomic conclusions. The occurrence of Hyposaurus within the Shendi Formation represents the first record of this genus from the Late Cretaceous of Africa and potentially extends its temporal range to the Campanian. Whereas this occurrence in the Late Cretaceous of Sudan supports previous hypotheses of an African origin for Hyposaurus, more complete material is needed for evaluating these hypotheses in a phylogenetic framework.We also wish to stress that the genus Hyposaurus requires detailed revision.