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A new specimen of ichthyosaur in a carbonate concretion from the Sinemurian (Lower Jurassic) of Black Ven, near Charmouth, Dorset, shows soft tissue preservation. The specimen is indeterminable at generic and specific level. It comprises the posterior portion of the axial skeleton and displays a lunate caudal fin preserved as an organic film. A thin band of phosphatized muscle tissue in the dorsal lobe of the tail indicates that some control of fin attitude was possible despite the absence of axial skeleton in the dorsal lobe.

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Envirotypes are persistent, environmentally induced, potentially inheritable phenotypes that have not been genetically selected for an environment. Unlike ecotypes, envirotypes do not breed true in different environments. The term ecophenotype should be restricted to phenotypic modifications resulting from disease, injury, physical restrictions on growth or to modifications that develop through use.

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Specimens of the gastropod Isfarispira septata gen. et sp. nov., from the Silurian of Central Asia, are characterized by a large, lenticular, multi-whorled shell with a flattened base, a low rate of expansion of the broad whorls, internal septa at intermediate growth stages and a prominent circumbilical flange which closed off much of the umbilicus. These morphological features reflect adaptation to life on a soft substratum, collectively serving to inhibit sinking into the soft sediment by increasing the area of the basal surface. I.

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Ostracodes are small (0.3-32 mm) bivalved crustaceans with an exceptional fossil record covering the last 540 million years of aquatic life; the group is still represented by nearly 8000 species (Podocopa and Myodoeopa). Only two major body plans prevail in the modern fauna if we except the enigmatic punciids. 'Body plan 1' corresponds to ostracodes (Myodocopida, Halocyprida) wilh a bilateral symmetry, a frontal polarity, a high activity level, an ellipsoidal shape, well designed for moving through water or soft muddy sediment, and (primarily) a circulatory system.

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Belemnites are common fossils in Mesozoic sequences. They have been used as biostratigraphical tools since the nineteenth century, but the only belemnite biozonation in general use is that of the Upper Cretaceous of northern Europe. The potential for broader application of belemnites in biostratigraphy is discussed with reference to first principles. In essence, belemnites are widespread, were relatively fast evolving and largely facies independent, in addition to being relatively simple to identify, abundant and robust.

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Intra-subzonal units, known collectively as 'horizons', are employed in Jurassic ammonite stratigraphy. Two basic types of 'horizon' are used by different authors. In France the unit is commonly employed as a sub-subzonal division which can be termed a 'zonule'. In Britain and Germany, however, the intra-subzonal unit typically used is more closely comparable to a faunal event. These faunal or 'biohorizons' are analogous to the hemerae of S. S. Buckman.

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Twenty-one bryozoan species are recorded from the Plio-Pleistocene deep-water marls of the island of Rhodes, Greece. The faunas occur in three sections where they are represented mostly by erect colonial morphotypes belonging to the cyclostomes (11 species) and the cheilostomes (five anascans and five ascophorans). Essentially on the basis of the known bathymetric distribution of the 19 extant species, a depth of deposition of 200 to 600 m is suggested, with a shallowing occurring towards the top of the sections.

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The echinoids of the Oxford Clay (Callovian-Oxfordian) of southern England have, until now, remained very poorly known. Three species are described: Eosalenia jessoni is shown to be a member of the Aspidodiadematidae, a rare deep-water family of Diadematoida, and Trochotiara superbum and Disaster moeschi are both reported from Britain for the first time.

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A Lower Cambrian coral, Moorowipora chamberensis, occurs in the Botomian Moorowie Formation near Moorowie Mine in the northern Flinders Ranges, South Australia. The coralla available for study are cerioid, with tripartite cerioid walls characterized by fibrous crystallites belonging to each corallite, separated by dark, fine-grained carbonate. The corallites were built by true individuals (polyps), as evidenced by their contraction to rounded form when clastic sediment was present within the corallum.

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The long-standing division of the lophophorate Phylum Brachiopoda into two units of Class rank, the Articulata and Inarticulata, is not supported by phylogenetic (cladistic) analysis. Using the PAUP program, two separate analyses, for seven extant brachiopod orders/suborders and for the combined extant and extinct groups, respectively, are consistent in identifying all chitinophosphatic-shelled stocks as a sister group to the carbonatic-shelled brachiopods, which include both 'inarticulates' and 'articulates' of previous schemes.

• Read more about Phylogenetic analysis and ordinal classification of the Brachiopoda