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Manubriate isograptids from the Castlemainian and Yapeenian (Arenig) of New Zealand, Australian, and Chinese collections are described and analysed in terms of population systematics. Pseudisograptus manubriatus (T. S. Hall, 1914) is divided into five subspecies, of which P. m. koi, P. m. harrisi, P. m. janus, and P. m. texanus are new; P. bellulus sp. nov. and five other Pseudisograptus species are described. A tentative phylogenetic scheme is constructed from their stratigraphic occurrence and a cladogram of pseudisograptids and other forms with manubriate features.

• Read more about Taxonomy, phylogeny, and variability of Pseudisograptus Beavis

Chandlerichthys strickeri n. gen. et sp., represented by two articulated specimens, is described from Middle Cretaceous deposits of the north slope of Alaska. This is the first articulated teleost species positively of Cretaceous age that has been found in freshwater deposits of North America. Although preservation is insufficient to permit detailed morphological description of the skull and caudal skeleton, it appears to be an osteoglossomorph.

• Read more about The first articulated freshwater teleost fish from the Cretaceous of North America

Recovery of over 900 hyoliths from fourteen localities in Oklahoma and Texas greatly increases the number of late Palaeozoic hyolith occurrences in North America; they include Lirotheca wilsoni Malinky and Mapes, 1983 and Darwinites grafordensis gen. et sp. nov. Many of the hyoliths lack opercula and taxonomically important features of the aperture, or they are crushed; these specimens are indeterminate. In Oklahoma the hyoliths are restricted to the dark grey to black, non-fissile, phosphatic shale members ( = 'core' shales) of Pennsylvanian cyclothems.

• Read more about New late Palaeozoic Hyolitha (Mollusca) from Oklahoma and Texas, and their palaeoenvironmental significance

The early Eocene insectivores of the Tsagan-Khushu locality in Mongolia are described. Two new genera and species of Nyctitheriidae, Bumbanius rarus and Oedolius perexiguus, and two new genera and species of Palaeoryctidae, Naranius infrequens and Tsaganius ambiguus are described and compared. A panto-lestid similar to Palaeosinopa and an unidentified form bearing a resemblance to Hyracolestes are also discussed.

• Read more about Early Eocene insectivores (Mammalia) from the People's Republic of Mongolia

Teratosaurus, based on a maxilla from the late Triassic of Germany, is shown to have been a rauisuchian, and not a dinosaur. The Family Teratosauridae, based on skull remains and skeletons from around the world, is not an early radiation of carnivorous dinosaurs: it consists of the skeletons of prosauropod dinosaurs and the skulls and teeth of rauisuchians, or unidentifiable archosaurs. Other records of middle Triassic dinosaurs are also suspect.

• Read more about The Late Triassic reptile Teratosaurus—a rauisuchian, not a dinosaur

Live and dead benthic faunas have been sampled offshore from Plymouth to assess the relationship between dead shell accumulations and living benthic communities. The live fauna (354 samples) has been sampled at approximately twenty-year intervals since 1895. The dead fauna (25 samples) was collected in one survey in 1980-1981. The live and dead mollusc and echinoderm (185 taxa) abundances are compared using multivariate statistical analysis (Detrended Correspondence Analysis). Three distinct communities are defined by this analysis, inhabiting shell-gravel, sand, and mud substrates.

• Read more about Community preservation in Recent shell-gravels, English Channel

The morphology and taxonomic identity of Semionotus Agassiz, 1832 is clarified, and the diversity of European species of Semionotus is assessed. Confusion about Semionotus dates back to Agassiz's original description in which he based the type species, S. leptocephalus, on a single specimen, and used it to argue that the Coburg Sandstone was Jurassic, a point necessary to support his concept of the threefold parallelism in nature. The specimen disappeared shortly thereafter, and subsequent authors, concluding that Agassiz's specimen of S.

• Read more about A revision of Semionotus (Pisces: Semionotidae) from the Triassic and Jurassic of Europe

Bodacrinus columnus gen. et sp. nov. from the Ashgill Boda Limestone of Sweden is described on the basis of dissociated stem material only. The column is unusual, being trimeric, and trilobate to sub-trapezoid in outline. Bodacrinus is presumed to be closely related to the disparid inadunate crinoid Ectenocrinus, the only other pelmatozoan known to have had a trimeric stalk. Relative stratigraphic positions indicate that Ectenocrinus may have been the ancestor of Bodacrinus.

• Read more about A new genus of inadunate crinoid with unique stem morphology from the Ashgill of Sweden

Quantitative data from Norway, Estonia, and the Llandovery area in Wales are used to re-evaluate the existence of the Stricklandia lens/S. laevis part of the Stricklandia/Costistricklandia evolving lineage. Two of the directed trends originally used to discriminate subspecies in material of the type Llandovery area fall within the same range of variation at roughly contemporaneous horizons in the Lower Silurian of Norway, Wales, and Estonia. These are reduction of the outer plates relative to the inner plates, and reorientation of the inner plates.

• Read more about A biometric re-evaluation of the Silurian brachiopod lineage Stricklandia lens/S. laevis

Autozooecial apertures sealed by perforate terminal diaphragms have been found in eleven species of British and Irish Carboniferous and Permian fenestrate Bryozoa. In their skeletal morphology, intra-colonial abundance, and distribution they resemble the perforate terminal diaphragms of polymorphs that are termed secondary nanozooecia in the Recent tubuloporinid cyclostome Plagioecia and the lichenoporid cyclostome Disporella. The former presence in fenestrates of single-tentacled non-feeding polymorphs comparable to those of Plagioecia and Disporella is inferred.

• Read more about Secondary nanozooecia in some Upper Palaeozoic fenestrate Bryozoa