The environmental setting and taphonomy of the insect fauna of the Insect Bed, Bembridge Marls (late Eocene; 36 Ma) of the Isle of Wight is described. Cluster analysis of taxonomic data on the insect fauna of a diversity of modern tropical environments, together with that of the Bembridge Marls, shows that the insects of the latter are characteristic of a primary sub-tropical/tropical forest subject to significant seasonal rainfall. A similar approach indicates that the sample of taxa preserved in the Insect Bed is biased toward insects from leaf litter and lower herbage microhabitats. External ornamentation of the cuticle is preserved on a micron scale, and the individual microfibrils of the procuticle can be distinguished. The insects of the Bembridge Marls are remarkable in preserving cuticle and mineralized internal tissues in a largely uncompacted state. Chemical analysis (py-GC/MS) reveals that the cuticle is composed of an aliphatic polymer, possibly due to polymerization of cuticular waxes during diagenesis. No chitin was detected. The soft tissues, which include sarcolemma and muscle fibres, are preserved through replacement in calcite.

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The taphonomy of invertebrates from 16th-century cesspits at St Saviourgate, York, was investigated. Earthworms, fly larvae and puparia are preserved through replication in calcium phosphate, a process facilitated by acidic cesspit pore water and by the presence of abundant organic matter, bones and shells. Features preserved by mineralization include muscles, blood vessels and setae. Non-mineralized invertebrate remains include puparia and beetles. Py-GC/MS (flash pyrolysis-gas chromatography/mass spectrometry) revealed a very high level of preservation of structural biomolecules, with all the protein and chitin markers that are evident in the living forms still being detectable in the divalent remains.

Two trilobite faunas of Late Ordovician (Katian) age are described from the Mayatas Formation in the Stepnyak region of north-central Kazakhstan. The older, oligotaxic fauna derives from flanks of a carbonate build-up, and is dominated by numerous Sphaerexochus specimens. Amphilichas is also relatively common, with Pliomerina and indeterminate asaphids present as rare components. The overlying unit of siliceous argillites contains a different assemblage, representing the raphiophorid biofacies and comprising seven genera. The poorly preserved fauna is dominated by blind trilobites (a new genus of trinucleid, the three-segmented raphiophorid Pseudampyxina, Malongullia?, Lonchodomas and Arthrorhachis) and at least two species of large-eyed Telephina, suggesting that they occupied the disphotic zone in deep water offshore. A single cranidium of the odontopleurid Primaspis is also present. The trinucleid, Iputaspis stepnyakensis gen. et sp. nov., has an unusual pit arrangement, with E1 and E2 aligned in sulci and all I arcs irregularly arranged. The Atansor area is located within the Stepnyak tectonostratigraphical unit, which probably represented an Ordovician active margin of the Kalmykkol–Kokchetav Microplate. Some of the genera represented in the faunas have affinities with Australia and South China and, also, there is a possible link to European peri-Gondwana.

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