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A new, third, specimen of Onychoselache traquairi from the Visean (Holkerian) of Scotland allows a significant revision of the anatomy of this stem-group elasmobranch. This first report of material from the Mumbie Quarry exposure of the Glencartholm fish beds presents a new reconstruction of Onychoselache showing broad-based cephalic and nuchal spines, and exceptionally large pectoral fins. Details of the jaws, braincase and postcranial skeleton demonstrate that Onychoselache is a well-characterized member of the Hybodontiformes.

• Read more about A new reconstruction of Onychoselache traquairi, comments on early chondrichthyan pectoral girdles and hybodontiform phylogeny

The Carnian (Late Triassic) flora of Lunz in Lower Austria is famous for an abundance of well-preserved bennettitalean and cycadalean foliage and reproductive structures. However, only the fertile remains have been studied in detail to date. Recently completed systematic macromorphological and cuticular analyses of leaf fossils from Lunz revealed that several forms previously accommodated in the genus Macrotaeniopteris do not represent ferns but rather Bennettitales assignable to the genus Nilssoniopteris.

• Read more about First record of Nilssoniopteris (Gymnospermophyta, Bennettitales) from the Carnian (Upper Triassic) of Lunz, Lower Austria

Bulk sampling of upper Campanian to lower-middle Maastrichtian coastal and lagoonal deposits in five sections of the Tremp Formation in the south-central Pyrenees yielded numerous neoselachian teeth. The fauna comprises nine taxa of which three species and one genus are new: Hemiscyllium sp., Lamniformes indet., Paratrygonorrhina amblysoda gen. et sp. nov., Coupatezia trempina sp. nov., Coupatezia sp., Coupatezia? sp., Rhombodus ibericus sp. nov. and Igdabatis indicus. The neoselachian fauna is dominated by small nectobenthic rays.

• Read more about Neoselachians from the upper Campanian and lower Maastrichtian (Upper Cretaceous) of the southern Pyrenees, northern Spain

The modern study of fossil crinoids began with J. S. Miller who, in 1821, described specimens from southern England, nearby Wales and other regions, and named several common Early Carboniferous genera. Later, in 1950-60, James Wright monographed all known Early Carboniferous crinoids from the British Isles. In spite of such previous scrutiny, we recognize here two new genera among species already described: Glamorganocrinus gen. nov. (type species: Ophiurocrinus gowerensis Wright, 1960) from South Wales and Mendipocrinus gen. nov.

• Read more about New cladid and flexible crinoids from the Mississippian (Tournaisian, Ivorian) of England and Wales

The interpretation of the lenses of schizochroal trilobite eyes as aplanatic doublets by Clarkson and Levi-Setti over 30 years ago has been widely accepted. However, the means of achieving a difference in refractive index across the interface between the two parts of each lens to overcome spherical aberration has remained a matter of speculation and lately it has been argued that the doublet structure itself is no more than a diagenetic artefact.

• Read more about Magnesium-rich intralensar structures in schizochroal trilobite eyes

A new basal balaenopterid genus and species, Archaebalaenoptera castriarquati, is described and compared with all the living and fossil members of the family Balaenopteridae and related fossil rorqual-like taxa. It was found in the Lower Pliocene of northern Italy, and is characterized by a supraoccipital with a transversely compressed anterior process, the zygomatic process of the squamosal diverging from the longitudinal axis of the skull, very long nasal bones, and subtle exposition of the parietal on the dorsal wall of the skull.

• Read more about A new basal balaenopterid whale from the Pliocene of northern Italy

New petrosal bones, assigned to Pucadelphys and Andinodelphys, from the Lower Paleocene of Tiupampa, Bolivia, are described. These remains provide new information on the anatomy of the ear region of these taxa. The re-examination of characters from the petrosal and basicranium shed light on the phylogenetic relationships of the three Tiupampan genera known from complete cranial remains (i.e. Mayulestes, Pucadelphys and Andinodelphys). The combination of dental, general cranial and basicranial characters led to two alternative hypotheses.

• Read more about The auditory region of Early Paleocene Pucadelphydae (Mammalia, Metatheria) from Tiupampa, Bolivia, with phylogenetic implications

We review controls on extensional growth rate and shell thickness in the extant oyster Crassostrea. Data on these shell parameters for the ecologically similar Bathonian oyster Praeexogyra hebridica, sampled at carefully selected sites, are then used to test a hypothesis that small size in contemporaneous marine bivalves of north-west Europe was the product of reduced salinity. The hypothesis is refuted, at least to the extent that some additional factor must be involved.

• Read more about Variation in growth-rate and form of a Bathonian (Middle Jurassic) oyster in England, and its environmental implications

The dicynodonts Oudenodon bainii and Tropidostoma microtrema are remarkably similar in most aspects of their morphology. The most obvious distinguishing feature is the presence of tusks and/or postcanine teeth in T. microtrema and their absence in O. bainii. However, some specimens of T. microtrema lack tusks or postcanine teeth. This variability raises the possibility that O. bainii and T. microtrema are not distinct species, but rather endpoints on a morphological continuum.

• Read more about An integrative approach to distinguishing the Late Permian dicynodont species Oudenodon bainii and Tropidostoma microtrema (Therapsida: Anomodontia)

Although their record extends back to the Early Ordovician, the occurrence of fossil starfish (Echinodermata: Asteroidea) is dependent almost exclusively upon horizons of exceptional preservation. Thus, asteroids found in Silurian obrution deposits of the English Midlands and Welsh Borderlands are particularly significant to an understanding of the early diversity of the group. Six species are described here: Hudsonaster? carectum sp. nov.

• Read more about Starfish diversity in the Wenlock of England