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A single carcase of the large Middle Jurassic ichthyosaurian Ophthalmosaurus sp. was rapidly decomposed in well-oxygenated bottom water of the Lower Oxford Clay Midlands basin. Parts of the soft tissues lying within anoxic sediments were subjected to slower rates of decay and portions of the integument are now preserved as replacements by bacterial and possibly fungal mats. Elements of the skeleton were encrusted with epibionts on their upper surfaces. Burial diagenesis has significantly affected some skeleton elements, with the infilling of voids with calcite, pyrite, and sphalerite.

• Read more about A taphonomic and diagenetic case study of a partially articulated ichthyosaur

A new functional analysis of the reversed heterocercal caudal fin of ichthyosaurs suggests that its function, other than propulsion, was not control of buoyancy, but to produce powerful downwards pitching moments. These moments were used to initiate manoeuvres, to dive after breathing at the surface, and, in one form, to feed. This model is of potential value in analysing the palaeobiology and evolution of ichthyosaurs and other marine reptiles with similar caudal fins.

• Read more about A reinterpretation of ichthyosaur swimming and buoyancy

A partial skeleton of a staurikosaurid, cf. Staurikosaurus sp. is described from the Ischigualasto Formation of Argentina. This specimen provides additional anatomical data for an evaluation of the phylogenetic affinities of the Staurikosauridae. Colbert's (1970) assignment of Staurikosaurus to the Dinosauria is supported. No synapomorphies exist to support close relationships between Herrerasaurus and Staurikosaurus.

• Read more about A staurikosaurid dinosaur from the Upper Triassic Ischigualasto Formation of Argentina and the relationships of the Staurikosauridae

The hippuritid rudist bivalve Torreites is described from the Maastrichtian of Oman and the United Arab Emirates. Together with the single fragment from the region on which T. milovanovici Grubic, 1979 was based, the specimens are placed in a newly recognized geographical subspecies of T. sanchezi (Douville, 1927), a species previously considered endemic to the Caribbean Province. The Arabian T. s. milovanovici Grubic differs from its Caribbean parent, T. s. sanchezi (Douville) (incorporating all previously recognized T. sanchezi, as well as T.

• Read more about A Caribbean rudist bivalve in Oman: island-hopping across the Pacific in the Late Cretaceous

Protocystites menevensis Hicks, 1872, from the Hypagnostus parvifrons Zone of the Middle Cambrian, near St David's, Dyfed, South Wales, is reconstructed and redescribed. It proves to be a cornute, and therefore a stem-group chordate, representing a plesion intermediate between that of Ceratocystis perneri (the most primitive known chordate) and that of Nevadaecystis americana. For purposes of reconstruction, tectonic distortion of the fossils was corrected by means of a computer program. The positions of oesophagus, stomach, and intestine are suggested in P.

• Read more about Protocystites menevensis—a stem-group chordate (Cornuta) from the Middle Cambrian of South Wales

Although the favositids have been traditionally interpreted as a group of Palaeozoic tabulate corals, there has been persistent speculation, particularly over the last decade, that they could be the massive basal skeletons of sponges and should be transferred to the Porifera. Two recent papers, claiming respectively the preservation of spicules and the fossilization of soft polyps, strongly focus the dispute. Here, all the evidence relating to the affinities of favositids, including these recent claims, is reviewed.

• Read more about A review of favositid affinities

The complex astogenetic patterns produced by the specialized, first few thecae (primordial thecae) of graptoloid rhabdosomes were conserved during evolution and provide a reliable guide to 'propinquity of descent' among diplograptids. Using this principle one can redefine their taxonomy, establish phylogenetically meaningful higher taxa, and obtain an improved understanding of diplograptacean phylogeny. The Diplograptacea comprises four major subclades.

• Read more about Evolution and phylogenetic classification of the Diplograptacea

The basal Rhaetic deposits of the Needwood Basin, Staffordshire, are of sandstone facies, in marked contrast to the well known bone beds and dark shales of the transgressive Westbury Formation which crop out elsewhere. The ochreous yellow sandstones contain abundant but poorly preserved bivalves (Eotrapezium sp.) together with an extensive ichnofauna which is dominated by Pelecypodichnus but also includes Arenicolites, Kouphichnium, Palaeophycus, Planolites, and Rusophycus in addition to various other trails and burrows.

• Read more about Trace fossils from Rhaetic shore-face deposits of Staffordshire

Eight species of hemiasterid echinoids, assigned to the genera Hemiaster (Bolbaster) and Psephoaster gen. nov., are described from Late Eocene to Middle Miocene strata of southern Australia. Seven of the species are new: the Late Eocene H. (B.) subidus, the Early Oligocene H. (B.) dolosus, the Early Miocene H. (JB.) verecundus, the Middle Miocene H. (B.) callidus, the Late Eocene P. lissos, the Late Oligocene P. apokryphos and the Early Miocene P. klydonos. A neotype is selected for H. (B.) planedeclivis Gregory, 1890. The five species of H.

• Read more about Taxonomy, evolution, and functional morphology of southern Australian Tertiary hemiasterid echinoids

Twelve Lower Triassic ammonoid specimens that retain four different 'colour' patterns are described. These 'colour' patterns are the oldest known for ammonoids; three genera (Dieneroceras, Prosphingites, and Owenites) are represented.

• Read more about The oldest ammonoid 'colour' patterns: description, comparison with Nautilus, and implications