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The skull of the dicynodont Lystrosaurus cf. curvatus is described from the Late Permian Madumabisa Mudstones of Zambia, in association with several Upper Permian genera. It demonstrates that the widespread Lystrosaurus, hitherto regarded as characteristic of the Lower Triassic, cannot be used in isolation as a biostratigraphical zone fossil. It appears that Lystrosaurus was a survivor of the Permo-Triassic extinction event, rather than a product of early Triassic diversification of other surviving forms.

• Read more about The dicynodont Lystrosaurus from the Upper Permian of Zambia: evolutionary and stratigraphical implications

A new pliosaur with a spatulate symphysis is described as Maresaurus coccai gen. et sp. nov. The holotype is from the upper levels of the Los Molles Formation (Lower Bajocian, Middle Jurassic) of the southern Neuquen Basin, central-western Argentina. Maresaurus coccai shares with Simolestes such synapomorphies as the absence of a dorso-medial foramen, lack of anterior interpterygoid vacuity, and fewer than 26 alveoli in the dentary. The autapomorphies of M.

• Read more about A new pliosaur from the Bajocian of the Neuquen Basin, Argentina

A giraffid skull and mandible from the early Mid Miocene Keramaria Formation at Thymania (Island of Chios, Greece) has enabled revision of the genus Georgiomeryx. The new specimen is compared with Canthumeryx syrtensis from Libya and Injanatherium from Iraq and Arabia. It is concluded that all these genera, which have flat and laterally directed horns, belong, together with Giraffokeryx, to the subfamily Canthumerycinae. New palaeomagnetic data from Chios combined with the presence of the fossil mammals provide new evidence for dating the locality to chron C5Br or early MN5.

• Read more about A giraffid from the middle Miocene of the Island of Chios, Greece

The hollow spines of an unusually well preserved specimen of the minute lingulate Acanthambonia are interpreted as having three functions. The short curved spines along the posterior margin are envisaged as attachment spines, supplementing a pedicle which is functional throughout ontogeny and regarded as anchoring the animal possibly to algal strands above the sea floor. Apart from rare undersized spines with tapering apices, the bulk of the spines on the shell surface are open-ended, with a length attaining half that of the shell itself.

• Read more about Functional significance of the spines of the Ordovician lingulate brachiopod Acanthambonia

'Ammon' is an interactive database that incorporates taxonomic, morphological, stratigraphical and locality information as well as digitized images. When necessary, a user can measure morphological features directly from an image using the mouse to mark points on which are based the measurement of distances, the calculation of ratios and derivation of logarithmic spiral parameters. Features such as ribs can be counted using the mouse, and counts extrapolated automatically to a standardized unit of measurement such as a half whorl.

• Read more about The Jurassic ammonite image database 'Ammon'

Multivariate statistical analyses of pollen and spore assemblages from Late Triassic to Early Cretaceous sedimentary strata in north-west Europe and earlier Jurassic deposits in Western Australia have allowed the identification of three major climatic-ecological groupings in each area. In each hemisphere the sporomorph groupings are interpreted as reflecting semi-tropical, cool-temperate, and intermediate climatic conditions.

• Read more about Mid Mesozoic floras and climates

The temporary, and often inconspicuous, nature of the bivalve periostracum has led to its relative neglect. As the first part of the valve to be secreted, onto which the calcareous shell is then deposited, the periostracum has great potential in governing basic valve form. Herein, periostracal thickness is shown to be an extremely variable character amongst members of the Bivalvia but within specific clades and life habits the range of variation is much narrower.

• Read more about The molluscan periostracum: an important constraint in bivalve evolution

The Kalkbank limestone of Thuringia, Germany, occurs within a condensed clastic-oolitic sequence lying below deposits associated with the Hirnantian (Ashgill) glaciation. Conodonts were first reported from this unit by Knupfer in 1967 but described only as morphospecies. On the basis of a new collection of over 25000 specimens, 13 species belonging to 11 genera are described. The discovery of M elements of Amorphognathus ordovicicus and A. ventilatus sp. nov. indicates an early Ashgill age for this limestone.

• Read more about Upper Ordovician conodonts from the Kalkbank Limestone of Thuringia, Germany

The Permian coral Numidiaphyllum, having an unusual septal arrangement and an aragonitic skeleton, has been classified in the Rugosa. The type species of Numidiaphyllum shows high intraspecific morphological variability and distinct granulation on septal faces. Ontogenetic development indicates that corallites show hexameral septal arrangement and cyclic mode of insertion. The genus has no specific morphologies that deny scleractinian affinities.

• Read more about The Permian coral Numidiaphyllum: new insights into anthozoan phylogeny and Triassic scleractinian origins

It has long been postulated that inoceramid bivalves had a long-lived planktotrophic larval stage because of their cosmopolitan distribution in the Cretaceous. This is now proven by the discovery of large larval shells preserved on inoceramid adult umbones from the Gault Formation at Folkestone. The developmental structure of these larval shells indicates that they were planktotrophic, living in the water column for in excess of 50 days. However, neither the inoceramid larval shell shape nor the hinge structure throw any new light on the taxonomic affinities of this extinct bivalve family.

• Read more about Inoceramid larval planktotrophy: evidence from the Gault Formation (Middle and basal Upper Albian), Folkestone, Kent