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A small assemblage of millimetric black carbonaceous compressions from the Wynniatt Formation of the Shaler Supergroup includes Chuaria circularis, Tawuia dalensis and Beltina danai. Also present are string-like remains that may be either pyritized vendotaeniacean filaments or small burrow fills. The occurrence of Tawuia is only the second known from North America.

• Read more about Carbonaceous megafossils from the Neoproterozoic Shaler Supergroup of Arctic Canada

The graptolite biostratigraphy of the persculptus to magnus Biozone interval (upper Hirnantian to lower Aeronian) in the Wye valley near Rhayader, central Wales, is described. Possible refinements to the graptolite zonal scheme are indicated, including informal subdivisions of the acuminatus and acinaces Biozones. Quantitative faunal assessment indicates that diplograptid: monograptid ratios are useful in indicating stratigraphical level. Selected taxa are described, including three new species, Normalograptus? wyensis, Pseudoglyptograptus barriei and ' Orthograptus' cabanensis.

• Read more about Uppermost Ordovician to Lower Silurian graptolite biostratigraphy of the Wye valley, central Wales

The brachiopod superfamily Strophomenoidea is reviewed and reclassified, with chief emphasis on the form and evolution of the cardinalia, the denticulation, the ventral muscle fields, and the dorsal side sept. There are six families without denticulation along the hinge line: the Christianiidae, Foliomenida Glyptomenidae, Leptaenoideidae, Rafinesquinidae, and Strophomenidae; and seven families with denticles along the hinge line: the Amphistrophiidae, Douvillinidae, Eopholidostrophiidae, Leptostrophiida, Shaleriidae, Strophodontidae and Strophonellidae.

• Read more about True Strophomena and a revision of the classification and evolution of strophomenoid and 'strophodontoid' brachiopods

The Ungulate brachiopod fauna from the Upper Ordovician Harju Series of southern Estonia consists of nine taxa, including the new acrotretid species Rhinotreta laeta, Opsiconidion praecursor, and Scaphelasma scutula. The unusual brachiopod-dominated assemblage was isolated by acid etching, mainly from a thin aphanitic limestone unit in the lower Pirgu Stage of the Viljandi core. The pitted micro-ornament on the larval and postlarval shell and the deep emarginature (pedicle notch) of the lingulide Rowellella minuta suggests that it belongs to the Zhanatellidae.

• Read more about Late Ordovician lingulate brachiopods from Estonia

In most ornamented dermal cranial bones of the larvae of the Lower Permian tetrapod Discosauriscus austriacus from Moravia, distinct rounded or oval pits are present. They are situated in, or close to, the sensory grooves and pit-lines. The diameter of each pit is c. 1 mm. The inner surface is sometimes smooth and consists mainly of smaller pits, depressions, or short canals which have small foramina at their bases. Such structures, designated as foraminate pits, have not previously been found in tetrapods.

• Read more about Electroreceptors in the Lower Permian tetrapod Discosauriscus austriacus

A new genus and species of anteosaurid dinocephalian, Australosyodon nyaphuli, is described from the Eodicynodon-Tapinocaninus Assemblage Zone, the lowermost biozone of the Beaufort Group in S Africa. This genus, closely allied to Syodon, is the first undoubted primitive anteosaurid dinocephalian from outside Russia, and indicates that the earliest therapsids were also present in the southern hemisphere.

• Read more about Australosyodon, the first primitive anteosaurid dinocephalian from the Upper Permian of Gondwana

The Upper Cretaceous Marsupites and Uintacrinus are among the morphologically most unusual of all fossil crinoids. Both have a large theca, ten extremely long arms, and lack any anchoring structure in both adult and juvenile stages; this morphology appears so unlike that of other articulate crinoid groups that earlier attempts to identify possible sister groups have been inconclusive. Cladistic analysis indicates that both genera are closely related to the Comasteridae, with Uintacrinus being less derived than Marsupites.

• Read more about Phylogeny and palaeobiology of Marsupites and Uintacrinus

Conchiolin sheets in corbulid bivalves have long been considered to offer some defence against predation by boring gastropods. Vermeij argued that most defences are exaptions rather than adaptations, but it has never been demonstrated whether conchiolin sheets in corbulids evolved in response to predation pressure or as a fortuitous benefit of an otherwise selected character (e.g. to retard shell dissolution, to prevent crack propagation, or to assist with hermetic sealing).

• Read more about Are conchiolin sheets in corbulid bivalves primarily defensive?

Five species of Upper Carboniferous orthostern scorpions are described from Britain and North America. Two are established taxa, and three are new: Palaeopisthacanthus vogelandurdeni sp. nov., Cryptoscorpius americanus gen. et sp. nov., and Corniops mapesii gen. et sp. nov. An additional species, Gymnoscorpius mutillidigitus gen. et sp. nov., is referred to the suborder Neoscorpionina, but is too incompletely known for its systematic position to be determined more accurately. The descriptions are based on fragmentary material from dispersed arthropod cuticle assemblages.

• Read more about Carboniferous orthosterni and their relationship to living scorpions

Transmission electron microscopy (TEM) is commonly used to characterize materials with respect to crystal structure, chemical composition, defect density and type, as well as other microstructural features. Observation of bone from the Upper Jurassic sauropod dinosaur Seismosaurus using this technique, reveals a unique bimodal crystallite structure which appears to have local preferred orientation. Most crystallites are small oblong grains, averaging approximately 100 nm long and 20 nm wide; larger hexagonal crystallites are also present, ranging from 80 to 400 nm in diameter.

• Read more about Microstructural analysis of bone of the sauropod dinosaur Seismosaurus by transmission electron microscopy