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The Aulacostephanidae (Ammonoidea) of the Oxfordian/Kimmeridgian boundary beds (Upper Jurassic) of southern England

Four areas in southern England centred on Swindon and Westbury (Wiltshire), Bourton (north Dorset) and the Dorset coast near Weymouth (south Dorset) have yielded well-preserved late Oxfordian and early Kimmeridgian (Upper Jurassic) ammonites in abundance. These ammonites belong principally to the aulacostephanid genera Ringsteadia and Pictonia, and their microconch equivalents Microbiplices and Prorasenia. Systematic descriptions of these genera are included herein.

Representing supraspecific taxa in higher-level phylogenetic analyses: guidelines for palaeontologists

As phylogenetic analyses become larger, one of the greatest methodological difficulties is representing speciose supraspecific clades in higher-level analyses (e.g. trilobites within studies of arthropod phylogeny). Several strategies have been proposed, including using representative single composite terminals or species-level exemplars, and various methods are currently used in the palaeontological literature. However, this is problematic, as simulation studies and empirical arguments in the systematics literature have clearly identified multiple exemplars as the optimal method.

A new arthropod in chain-like associations from the Chengjiang Lagerstätte (Lower Cambrian), Yunnan, China

A new arthropod, Synophalos xynos gen. et sp. nov., is described from the Lower Cambrian of the Chengjiang Lagerstätte, Yunnan, China. It is provisionally assigned to Crustacea, Waptiida and Waptiidae. Just one example of an isolated individual of S. xynos is known. Typically, individuals of the new species occur together in similar, robustly integrated chain-like associations. Such a strongly linked configuration is apparently unique for any arthropod, fossil or living.

The extraordinary trilobite Fenestraspis (Dalmanitidae, Synphoriinae) from the Lower Devonian of Bolivia

The hitherto poorly known, monotypic trilobite genus Fenestraspis from the Lower Devonian of Bolivia is revised and its original assignment to the Synphoriinae supported. The thoracic morphology of the genus remains very poorly known. Fenestraspis is morphologically unusual because of the development of extensive fenestrae in the pleural region of the pygidium and apparently of the thorax; the presence of upwardly directed spines on the cephalon, thorax and pygidium; and the exceptionally large and highly elevated eyes with the palpebral rim projecting outwards above the visual surface.

Taxonomy of Quaternary deep-sea ostracods from the western North Atlantic Ocean

Late Quaternary sediments from Ocean Drilling Program (ODP) Hole 1055B, Carolina Slope, western North Atlantic (32°47.041' N, 76°17.179' W; 1798 m water depth) were examined for deep-sea ostracod taxonomy. A total of 13 933 specimens were picked from 207 samples and c. 120 species were identified. Among them, 87 species were included and illustrated in this paper. Twenty-eight new species are described.

An assessment of variability in theropod dinosaur remains from the Bathonian (Middle Jurassic) of Stonesfield and New Park Quarry, UK and taxonomic implications for Megalosaurus bucklandii and Iliosuchus incognitus

The assemblage of large-bodied theropod remains from the Taynton Limestone Formation (middle Bathonian) of Stonesfield, Oxfordshire and the Chipping Norton Limestone Formation (lowest Bathonian) of New Park Quarry, Gloucestershire, UK is interpreted as monospecific. An assessment of morphological variation in theropod fossils from these localities reveals no taxonomically-significant variation among remains representing large-bodied individuals. Previous observations of anatomical variation among femora, ilia and scapulocoracoids are attributed to postmortem damage and deformation.

First record of the cirripede genus Stramentum (Thoracica, Scalpelliformes) from the Upper Cretaceous of Japan

The scalpelliform genus Stramentum is described from upper Turonian–Coniacian (Upper Cretaceous) strata in the Mikasa area, Hokkaido (Japan), documenting the first record of the genus from the north-west Pacific Realm. The single articulated skeleton, which is horizontally embedded in a dark grey laminated mudstone, is specifically indeterminate because capitular plates are missing. However, peduncular morphology resembles that of S. (S.) pulchellum (Sowerby Jr), which has been described from the Cenomanian–Turonian of Europe.

Cleptoparasitism and detritivory in dung beetle fossil brood balls from Patagonia, Argentina

Traces within traces is a new ichnological field that is meant to shed light on significative palaeoecological aspects. Dung beetle fossil brood balls (Coprinisphaera ispp.), from the Middle Eocene – Lower Miocene Sarmiento Formation of Patagonia, Argentina, show two different trace fossils excavated in its infillings and/or wall that reveal the presence and relationships among different components of past dung communities. Tombownichnus pepei n. isp.

A new tristichopterid (Sarcopterygii, Tetrapodomorpha) from the Upper Famennian Evieux Formation (Upper Devonian) of Belgium

Additional material of a large specimen of tristichopterid fish from the Upper Famennian Evieux Formation of Belgium is described. This large fish was previously assigned to Tristichopteridae gen. et sp. indet. due to the lack of diagnostic anatomical data. New available material consists of the internal surface of the parietal shield, vomers and anterior part of the parasphenoid, subopercular and submandibulo-branchiostegal bones, and an internal view of the anterior part of the mandible. A possible autapomorphy of the new form from Belgium, Langlieria socqueti gen. nov. et sp.

Rooting phylogenies of problematic fossil taxa; a case study using cinctans (stem-group echinoderms)

Extinct clades whose higher-level relationships are problematic or disputed pose a particular problem for phylogenetic analysis because of the difficulty of establishing a convincing root. Cinctans are a problematic group of primitive preradiate echinoderms whose morphology is so distinct that few characters can be usefully homologized with any other group.
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