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Smooth-shelled atrypoid brachiopods, Dubaria varians (Poulsen, 1943) and Dubaria sp. nov., occur in Llandovery strata of western North Greenland in cryptic habitats associated with biostromes and reefs. This ecological preference probably explains their patchy spatial and temporal distribution. It may explain the stratigraphic distribution of Dubaria since other species in the genus also occur in association with reefs.

• Read more about Autecology and distribution of the Silurian brachiopod Dubaria

Two new species of Eskdalia are described from the Lower Carboniferous of Siberia. Eskdalia has been thought to possess true leaf scars produced as a result of leaf abscission. The new specimens similarly have misleading oval areas thought to indicate leaf abscission. However, closer examination and consideration of sedimentary effects upon preservation, shows that leaves are still attached although their preservation is poor. The genus is rediagnosed and compared with other similar lepidophytes.

• Read more about A reappraisal of the Lower Carboniferous lepidophyte Eskdalia Kidston

The Grammysiidae are a Palaeozoic family of mainly infaunal anomalodesmatan Bivalvia that lived in very shallow marine environments. Since they were edentulous, the problem of shearing of the valves during burrowing was overcome by the cincture (radial furrows and ribs), which folded the ventral margin. This folded venter provided an active saw during burrowing.

• Read more about Mode of life and autecology of Silurian–Devonian Grammysiidae (Bivalvia)

Janeia silurica Liljedahl, 1984 from the Silurian of Gotland has unusual characters in common with the deposit-feeding nuculoids and the systematically controversial solemyoids, generally considered to have a life habit intermediate between deposit- and suspension-feeding but which in fact lives in symbiosis with chemoautotrophic bacteria. The extensive silicified material available is occasionally extremely well-preserved, reflecting soft-part anatomy of the muscles of the foot as well as of the mantle. J.

• Read more about Janeia silurica, a link between nuculoids and solemyoids (Bivalvia)

Evidence from orthocone septal strength implies approximate depth limits of 200 m for the near-shore dwelling actinocerids, 500 m for large orthocerids, and no more than 1500 m for the small pelagic orthocerids found in 'graptolitic shales'. These estimates refer to the initial depositional depth of fully septate conchs; not the habitat depth of pelagic species, nor the occurrence of fragmented and reworked specimens. The further interpretation of the autecology of the large orthocerids must be based either on the distantly related, coiled genus Nautilus, or their large coleoid descendants.

• Read more about Growth analysis of Silurian orthoconic nautiloids

New material of the antiarch Bothriolepis, from the Gogo Formation (early Upper Devonian, Canning Basin, Western Australia), provides morphological details of the visceral jaw elements, which were not previously known in antiarchs. The palatoquadrate lacks a high orbital process, and was attached to the ventral part only of the suborbital (mental) plate. This shows that the ethmoidal region of the braincase must have been considerably deeper than previously thought.

• Read more about Reconstruction of the jaws and braincase in the Devonian placoderm fish Bothriolepis

The distribution of the commoner species, most of which are brachiopods, in thirty large collections from the late Llandovery of the Welsh Borderland gives extra data on the previously published Lingula, Eocoelia, Pentamerus, Stricklandia, and Clorinda communities. The constituents of the communities were not usually interdependent, but lived together in comparable habitats with similar external parameters. The depths at which the communities lived are reviewed and it is concluded that the total depth range of the community spectrum was probably less than 200 m.

• Read more about Review of the distribution of the commoner animals in Lower Silurian marine benthic communities

Dubbolimulus peetae gen. et sp. nov. is described from freshwater strata of middle Triassic age near Dubbo, New South Wales, and is referred to the new family Dubbolimulidae. Previous reports of xiphosurans from Australia are reviewed; Pincombella belmontensis Chapman, 1932 and Hemiaspis tunnediffei Chapman, 1932 are shown to be respectively an insect and a trilobite.

• Read more about A new freshwater limuloid from the Middle Triassic of New South Wales

Ramseyocrinus Bates, 1968, has hitherto been included in the family Eustenocrinidae Ulrich, 1925 but it differs from all other members of this family in having only four radials, an anal X which is supported by two radials (rather than two or three superradials, or a brachianal and superradial), a cup which is about as wide as high, and a column which is tetrameric proximally and tetragonal holomeric distally. A new family Ramseyocrinidae, is erected for this genus.

• Read more about Ramseyocrinus and Ristnacrinus from the Ordovician of Britain

The Palaeocene pike Esox tiemani combines many typically esocid features such as an elongate body depressible and canine teeth, elongate snout and jaws, almost straight preopercle, small second and third hypurals separated by a gap, large ethmoid process on the ectopterygoid, and anteriorly lobed scales with other features in which it is intermediate between Recent umbrids and esocids. Branchiostegal rays are almost equally divided between the ceratohyal and epihyal, while in Recent umbrids they are more numerous on the ceratohya and in Recent esocids they are more numerous on the epihyal.

• Read more about Osteology of the Palaeocene teleost Esox tiemani