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The lunate caudal fin, characteristic of post-Triassic ichthyosaurs, is often interpreted as functioning as a reversed shark's tail, generating vertical as well as horizontal components. The functional morphology of the shark's tail is discussed, and considered far from well understood. Although the ichthyosaurian tail is superficially similar to a reversed heterocercal tail, the two structures are not strictly analogous and there are functional grounds why the ichthyosaurian tail should not generate vertical forces.

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The non-marine tetrapods of the Permian and Early Triassic experienced four significant episodes of extinction during a time of relatively high turnover at the family level. The Artinskian, Ufimian, and Scythian extinctions appear genuine, but the Tatarian extinction is compromised by spurious data. The quality of the Tatarian data is considered in the light of the poor stratigraphical record for the Late Permian and Permian-Triassic boundary.

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A rich lamniform selachian fauna, comprising twelve species, is recorded from the informal B. mammillatus zone of the Kristianstad Basin. Five new taxa, including a North American one, are introduced: Archaeolamna gen. nov., with the species A. kopingensis (Davis, 1890) and the subspecies A. k. judithensis subsp. nov. from the Campanian of Montana, USA, Scapanorhynchus perssoni sp. nov., Anomotodon hermani sp. nov. and Carcharias aasenensis sp. nov.

• Read more about Biology, dental morphology and taxonomy of lamniform sharks from the Campanian of the Kristianstad Basin, Sweden

The slow progress of quantitative methods in palaeontology during the past decade threatens the survival of palaeontology. Different phenetic and cladistic methods produce different estimates of phylogenetic relations; none of these estimates is a priori more authoritative than others; taxonomic and phylogenetic certainty is unattainable, and probabilistic estimates of phylogeny must be accepted. Phenetic methods are well suited to estimating phylogenies from palaeontological data. Objective definitions of taxonomic entities and attribute states are essential in phylogenetic analysis.

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Myodocope ostracodes are represented worldwide in a variety of modern environments as benthic, nektobenthic or exclusively planktonic organisms. Their Silurian ancestors form one component of the early Palaeozoic marine crustacean fauna. Aspects of biology (body plan, functional morphology, behaviour relevant to the interpretation of the fossil record) newly investigated by, for example, video-recordings t described.

• Read more about Recent and early Palaeozoic myodocope ostracodes: functional morphology, phylogeny, distribution and lifestyles

The primitive ichthyosaur, Grippia cf. G. longirostris occurs in Lower Triassic beds near Wapiti Lake, British Columbia. The material includes a well-preserved forelimb and a partial foot, and allows for a new interpretation of the homologies of the elements of the carpus and tarsus. Four distal carpals and five metacarpals are present in the hand, the element previously identified as the fifth distal carpal being reidentified as the fifth metacarpal. Similarly, the proximal element of the fifth digit in the foot is reidentified as the fifth metatarsal.

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The Phylloceratina, Lytoceratina and Ammonitina of the upper Valudavur Formation (Valudavur Group or Anisoceras Beds of authors) collected near Pondicherry, south India, are revised on the basis of the collections of the Natural History Museum, London, notably those described by Forbes (1846). Twenty species, referred to thirteen genera, are recognized.

• Read more about Non-heteromorph ammonites from the Upper Maastrichtian of Pondicherry, south India

The structure and function of the pectoral fin joint and operculum in antiarchs (Devonian placoderm fishes) are re-examined in the light of new evidence from primitive Early Devonian representatives from South China, and acid-prepared material from the Late Devonian of Western Australia. The characteristic dermal brachial process of advanced antiarchs is absent in Yunnanolepis, and rudimentary in Procondylolepis.

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The conulariid test has been interpreted as homologous to the theca of coronatid scyphozoans, but recently it has been claimed that the conulariid test and coronatid theca are fundamentally dissimilar. This claim is based largely on putative microstructural characteristics of conulariid tests. Examination of sectioned conulariids using scanning electron microscopy reveals that their microstructure is similar to that of the coronatid theca.

• Read more about Microstructure and growth of the conulariid test: implications for conulariid affinities

The first unequivocal fossil dermopteran (flying lemur) is reported here. It comes from the Tertiary Basin (Upper Eocene) of Krabi, Thailand, and appears to be close to the ancestor of the extant forms. Other supposed dermopterans reported previously from North America cannot be referred to this Order.

• Read more about First fossil flying lemur: a dermopteran from the Late Eocene of Thailand