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New Pteraspididae from the upper Silurian and lower Devonian of arctic Canada differ from established members of the family in possessing a single orbito-cornual plate and a pineal plate enclosed by the dorsal disc. A new subfamily of the Pteraspididae, the Anchipteraspidinae, is raised to accommodate five species of the new genera Anchipteraspis, Ulutitaspis, and Rhachiaspis. Consideration of the growth and structure of the shields of the Anchipteraspidinae indicates their close relationship to both the Cyathaspidinae and early members of the Pteraspidinae.

• Read more about A new subfamily of the Pteraspididae (Agnatha, Heterostraci) from the upper Silurian and lower Devonian of Arctic Canada

A nearly complete lower jaw is described of the longirostrine mesosuchian crocodilian Sunosuchus thailandicus BufTetaut and Ingavat (1980), from the Phu Kradung Formation (early Jurassic) of north-eastern Thailand, and the affinities of the genus are discussed. The jaw is large and robust, with a long symphysis, and each dentary contains about thirty teeth. Despite the unusually elongated mandibular symphysis the genus is referred to the Goniopholididae rather than to the Pholidosauridae, on the basis of the skull characters present in the Chinese species S. miaoi Young (1948).

• Read more about The lower jaw of Sunosuchus thailandicus, a mesosuchian crocodilian from the Jurassic of Thailand

The cryptic micromorph ammonite Neosaynoceras Breistroffer, 1947 is redescribed and shown to be a Cenomanian offshoot of Salaziceras Breistroffer, 1936 of the Flickiidae. Salaziceras and Neosaynoceras are separated from the remaining Flickiidae as Salaziceratinae subfam. nov.

• Read more about The affinities of the Cretaceous ammonite Neosaynoceras Breistroffer, 1947

Stromatoporoids in argillaceous level-bottom limestones of the Upper Visby Beds in the Silurian of Gotland, Sweden, show a variety of features of growth form, within a spectrum of coenosteal shapes from laminar through low to high domical. Many coenostea show interdigitations of sediment in their margins, attributable to intermittent sedimentation, while others show abrupt changes in growth direction, which are the results of movement, often leading to overturning.

• Read more about Patterns of stromatoporoid growth in level-bottom environments

The fossil material of a 760 mm long crocodilian, Terrestrisuchus gracilis gen. et sp. nov., from a late upper Triassic fissure filling in the Carboniferous limestone of the old Pant-y-ffynon quarry near Cowbridge, Glamorgan, is described. The quadratojugal is parallel sided and the squamosal lacks a descending process. A hard secondary palate is formed by the maxillae and premaxillae. A fenestra pseudorotundum is present but the pterygoids were not sutured to the braincase. The Eustachian tubes were ramified. A prearticular is present. The teeth are recurved, flattened, and bear serrations.

• Read more about A late upper Triassic sphenosuchid crocodilian from Wales

The Taphrognathus transatlanticus Range Zone is proposed to replace the earlier defined, and subsequently rejected, Taphrognathus varians-Cavusgnathus-Apatognathus Assemblage Zone. It is based on the occurrence and range of the conodont species Taphrognathus transatlanticus sp. nov. in strata of Visean age on both sides of the Atlantic Ocean. The T. transatlanticus conodont Range Zone is present in the upper part of the S2 Zone of the Avon Gorge in Great Britain and the lower B Subzone of the Windsor and Codroy groups of Atlantic Canada.

• Read more about The Dinantian Taphrognathus transatlanticus conodont Range Zone of Great Britain and Atlantic Canada

The Ordovician diploporite fauna from the Oslo Region is examined morphologically and taxonomically. The brachioles of Protocrinites are shown to be biserial. Pore-structures are described, including peripore connections and the structure of the skeletal mesh work. Internal morphological structures indicate a possible basal nerve ring and oral ring structures. Aspects of ontogeny and phylogeny dealt with include changes in plate number, an increased complexity of pore structures, and possibly an increased complexity of brachioles.

• Read more about The Diploporita of the Oslo region, Norway

A diverse assemblage of permineralized conifer remains has been discovered in late Palaeozoic limestones from the mid-continent of North America, near Hamilton, Kansas. Ovulate cones described as Lebachia lockardii sp. nov., support the structural homologies among cordaites, primitive conifers, and modern conifers proposed by Florin, and reveal anatomical features that are remarkably similar to those of many extant conifers.

• Read more about Permineralized ovulate cones of Lebachia from late Palaeozoic limestones of Kansas

Ammonites polyopsis Dujardin, 1837 is referred to the genus Placenticeras Meek, 1876 and shown to have priority over Ammonites ribourianus d'Orbigny, 1850, Placenticeras depressum Hyatt, 1903, P. grossouvrei Hyatt, 1903 (non Semenov, 1899) (renamed P. hyatti Diener, 1925), P. incisum Hyatt, 1903, P. schlueteri Hyatt, 1903, and P. crassatum Hyatt, 1903 amongst others. This plethora of names results from early failure to recognize the strong dimorphism present in the species. Recognition of this dimorphism and the wide intraspecific variation seen in P.

• Read more about Ammonites polyopsis Dujardin, 1837 and the Cretaceous ammonite family Placenticeratidae Hyatt, 1900

Type and topotype material of middle and upper Cambrian odontopleuracean trilobites is described from the Soviet Union and new family and generic diagnoses are given. Belovia, Acidaspidina, and Eoacidaspis are assigned to the Family Eoacidaspididae, Acidaspides and Acidaspidella to the Odontopleuridae. Holaspid cranidia of Acidaspides resemble those of early Ordovician Primaspis (Odontopleurinae), pre-holaspid growth stages resemble certain Miraspidinae, and Acidaspidella resembles Leonaspis.

• Read more about Cambrian origins of the odontopleurid trilobites