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The majority of inoceramid bivalves occurring in Late Jurassic temperate realm assemblages can probably be assigned to the genus Retroceramus. Although there are a few transitional forms, Retroceramus can generally be distinguished from the better-known genus Inoceramus by features of both the external and internal shell morphology.

• Read more about Late Jurassic inoceramid bivalves from the Antarctic Peninsula and their stratigraphic use

A new broad-headed species of the primitive lungfish Dipnorhynchus, D. kiandrensis, is described from an isolated skull roof found in the Emsian (Lower Devonian) Lick Hole Limestone at the Ravine, near Kiandra, New South Wales. It is slightly older than the specimens of D. sussmilchi previously described. The existence of extra bones, particularly T and 14, in the cheek of this genus is substantiated. Arguments favouring the existence of H between Z and A in primitive dipnoans are presented. The ethmoidal canals are shown to be less complex in Dipnorhynchus than in Chirodipterus.

• Read more about A new species of the lungfish Dipnorhynchus from New South Wales

A new genus and species of tarrasiiform fish is described from the Chesterian (Upper Mississippian) Bear Gulch Limestone member of the Heath Formation, Montana, U.S.A. Among the distinguishing osteological features of the order that can now be established are premaxillae sutured in the midline, separate rostral and postrostral bones, two pairs of nasals, and a skull roof consisting of paired frontals, parietals, and postparietals. A tentative relationship is proposed with the base of the radiation of the order Palaeonisciformes.

• Read more about A new actinopterygian fish from the Mississippian Bear Gulch Limestone of Montana

Blastoidocrinus antecedens, from the early Arenig Bolahaul Member of the Ogof Hen Formation at Llangynog, South Wales, is the oldest known parablastoid and the first recorded from the British Isles. It is characterized by almost smooth deltoids with weakly scalloped margins and a stellate thecal outline. A single deltoid is known from the Treionverth Formation (Upper Arenig) of Anglesey.Currents in the respiratory cataspires of parablastoids entered the aboral slits and exited through the adambulacral pores, contrary to Hudson's (1915) interpretation.

• Read more about A parablastoid from the Arenig of South Wales

New methods for the separation of microvertebrate fossils from particulate sediment residues are based on preferential wetting of the bone particles by water-immiscible solvents in aqueous media. Three embodiments of this basic idea are described, two of them involving adhesion of the bone particles to solid or gelatinous materials (polystyrene or high molecular weight hydrocarbons), whilst the third relies on simple two-phase liquid mixtures. The new methods give results which compare favourably with those from conventional techniques of bone-enrichment, and at minimal or negligible cost.

• Read more about Fossil bone recovery from sediment residues by the 'Interfacial Method'

A structurally preserved and distinctive microbiota composed of sphaeromorphic acritarchs and filamentous microfossils has recently been recovered from shales of the Aultbea Formation, Torridon Group, on Tanera Beg, Summer Isles, N.W. Scotland. The dominant sphaeromorphs comprise single vesicle; plurivesicular aggregates, and envelopes containing up to several tens of vesicles. They closely resemble those occurring in shales of the Roper Group, Northern Territory, Australia.

• Read more about Upper Proterozoic microfossils from the Summer Isles, N.W. Scotland

A description is given of a new and well-preserved specimen of Ardeosaurus brevipes from the Solnhofen facies of the Kimmeridgian of Bavaria, Germany. The specimen is in the Paleontological Museum of Uppsala University (PMU.R58). The type of A. brevipes is missing and only a cast represents the poorly preserved original. The new specimen has characters exemplifying the similarities between the two species of Ardeosaurus: A. brevipes and A. digitatellus. Differences between Ardeosaurus and a similar genus Eichstaetti-saurus are clarified and emphasized.

• Read more about Osteology of the Jurassic lizard Ardeosaurus brevipes (Meyer)

A single lytoceratid ammonite from the Jamesoni or Ibex Zone of the Lower Lias of Clandown Colliery Quarry, Radstock, Avon, is made the holotype of Derolytoceras (D.) radstockense sp. nov. It is the first record in Britain of a genus that is largely restricted to Tethyan areas of south and central Europe.

• Read more about A rare lytoceratid ammonite from the Lower Lias of Radstock

A fused conodont cluster, comprising six distacodontiform elements and one oistodontiform element, from upper Ordovician limestones of the Aleqatsiaq Fjord Formation of Washington Land, north Greenland, is described. A notable microstructural feature of all the elements is the presence of oblique striations along the anterior margins of the lateral faces. The distacodontiform elements are similar to elements included in Acodus?

• Read more about A fused cluster of coniform conodont elements from the late Ordovician of Washington Land, western north Greenland

Leckhamptonella llewellyae gen. et sp. nov., is described from the Middle Jurassic (Inferior Oolite; Aalenian) of the Cotswold district, England. Although known only from fragmentary material, it is recognizable as the remains of a new serial-segmented member of the Udoteaceae (Chlorophyta). It is compared with Boueina and Arabicodium (both Mesozoic) and Halimeda (Cretaceous-Recent), and shows certain affinities with the latter especially. The evolution of serial-segmented Udoteaceae from Lower Palaeozoic to Recent is briefly reviewed.

• Read more about A new calcareous green alga from the Middle Jurassic of England: its relationships and evolutionary position