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Accurate hypotheses of primary homology are fundamental to many aspects of the systematics and palaeobiology of fossils. They are particularly critical for conodonts: virtually all areas of conodont research are underpinned by homology, yet the majority of conodont taxa are found only as disarticulated skeletal elements, and hypotheses of element homology are inferred from morphological comparisons with complete skeletons. This can cause problems in taxa where more than one location within the conodont skeleton is occupied by elements with similar morphology.

• Read more about Morphological criteria for recognising homology in isolated skeletal elements: comparison of traditional and morphometric approaches in conodonts

Abundant material from a new quarry excavated in the lower Cambrian Emu Bay Shale (Kangaroo Island, South Australia) and, particularly, the preservation of soft-bodied features previously unknown from this Burgess Shale-type locality, permit the revision of two bivalved arthropod taxa described in the late 1970s, Isoxys communis and Tuzoia australis. The collections have also produced fossils belonging to two new species: Isoxys glaessneri and Tuzoia sp.

• Read more about The bivalved arthropods Isoxys and Tuzoia with soft-part preservation from the Lower Cambrian Emu Bay Shale Lagerstätte (Kangaroo Island, Australia)

A collection of silicified trilobites extracted from samples obtained by F. Nansen from the Upper Ordovician of Khabarovo, Pai Khoi, Russian Arctic is dominated by two new species of the proetide Lasarchopyge, a genus known hitherto only from the Argentine Precordillera. Comparison of Lasarchopyge with Scharyia reveals a range of common characters that support inclusion of both genera in the same family. The rest of the fauna comprises a metagnostid (Trinodus elspethi), an asaphid (Isotelus sp.), two remopleuridids (Remopleurides cf. caelatus and R. sp. nov.

• Read more about Silicified Upper Ordovician trilobites from Pai-Khoi, Arctic Russia

An isolated anterior caudal vertebra from the Qingshan (= Ch'ing shan) Formation (Early Cretaceous) of Shandong Province, China, is redescribed and shown to be an advanced diplodocid sauropod. This specimen possesses several derived character states that are typically observed in advanced diplodocoids or diplodocids, including the following: a mildly procoelous centrum; a deep pit-like pneumatic fossa immediately below the caudal rib; wing- or fan-shaped caudal ribs; and complex lamination of the neural spine.

• Read more about The first diplodocid from Asia and its implications for the evolutionary history of sauropod dinosaurs

The extinct mysticete fauna of the North East Atlantic is primarily known from the abundant but fragmented Belgian specimens. Compared to the well-preserved contemporary mysticete fauna from deposits in North America, there are only few near complete European Miocene mysticete fossils. Presented here is a new, almost complete fossil baleen whale Uranocetus gramensis gen. et sp. nov. from the Upper Miocene Gram Formation in South West Denmark.

• Read more about A new baleen whale from the Late Miocene of Denmark and early mysticete hearing

Echinoid teeth are without doubt the most complex and highly specialized skeletal component to have evolved in echinoderms. They are biomechanically constructed to be resilient and tough while maintaining a self-sharpening point. Based on SEM analysis of isolated tooth elements collected primarily from the Ordovician and Silurian of Gotland, we provide a detailed structural analysis of the earliest echinoderm teeth.

• Read more about Origins and biomechanical evolution of teeth in echinoids and their relatives

The Silurian and Lower Devonian pterygotid eurypterids were the largest of all arthropods, but their origin and early evolution are poorly understood. Pterygotus? ventricosus from Kokomo, Indiana, is shown to be the most basal of the pterygotids and constitutes the sister taxon to the rest of the clade. P.? ventricosus has walking appendages similar to those of Slimonia, which is the sister taxon of pterygotids.

• Read more about The origin of pterygotid eurypterids (Chelicerata: Eurypterida)

Stylonurid eurypterids (Arthropoda: Chelicerata) include some of the largest known arthropods – bizarre sweep-feeding hibbertopterids from the Carboniferous to end-Permian. New material of Drepanopterus abonensis, a stylonurid from the Late Devonian (Famennian) of Portishead, south-west England, offers key insights into this genus and its affinities.

• Read more about Redescription of Drepanopterus abonensis (Chelicerata: Eurypterida: Stylonurina) from the late Devonian of Portishead, UK

A new suite of arthropod trace fossils, attributed to a decapod crustacean, is described from the Lower Jurassic Saltford Shale Member of the Blue Lias Formation of Southam Cement Works Quarry, eastern Warwickshire, England. Solusichnium southamensis igen. et isp. nov. consists of small, isolated, bilaterally symmetrical, suboval hypichnia, comprising three regions. The concave anterior region contains imprints of chelate appendages, antennae and antennules. The elongate middle region contains abdominal appendage imprints that extend laterally, separated by a bifurcated medial imprint.

• Read more about A new arthropod resting trace and associated suite of trace fossils from the Lower Jurassic of Warwickshire, England

Skull shape variation in thalattosuchians is examined using geometric morphometric techniques in order to delineate species, especially with respect to the classification of Callovian species, and to explore patterns of disparity during their evolutionary history.

• Read more about Morphospace occupation in thalattosuchian crocodylomorphs: skull shape variation, species delineation and temporal patterns