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Two new bryozoan (ectoproct) genera are part of the fauna of the Late Mississippian carbonate facies in Utah, Idaho, Wyoming, and Montana. Helenopora gen. nov. is widespread and abundant whereas Astralochoma gen. nov. is more restricted and sparse. Gross external features of the bryozoan colonies (size, colony form, and shape of zooecial tubules) resemble chaetetiform colonies. Internal characteristics of the two new genera show them to be bryozoans with distinctive budding patterns.

• Read more about New chaetetiform trepostome Bryozoa from the Upper Mississippian of the western United States

Fossil platanoid leaves from the Palaeocene of Mull, north-west Scotland, are assigned to Platanites hebridicus Forbes. The leaves closely resemble those of extant Platanaceae, and differ only in being pinnately compound. Each leaf consists of a shallowly three-lobed terminal leaflet and two smaller asymmetric lateral leaflets. Reproductive structures associated with the fossil foliage are also similar to those of extant Platanaceae, and the only unequivocal differences are the ellipsoidal achene shape and the smaller number of achenes per fruiting head in the Palaeocene material.

• Read more about Morphology and phylogenetic significance of the angiosperm Platanites hebridicus from the Palaeocene of Scotland

A right dentary fragment and two postcanine teeth from the upper shale member of the Chinle Formation (Late Triassic: Norian) at Bull Canyon, Guadalupe County, New Mexico represent a new species of cynodont, Pseudotriconodon chatterjeei. P. chatterjeei differs from P. wildi from the Norian of Luxembourg, type and only other known species of Pseudotriconodon, by its smaller size and striated enamel.

• Read more about A Late Triassic cynodont from the American south-west

Faunal data are matched against major sedimentary facies to interpret benthic palaeoecology and palaeogeographical evolution through the Lower Leintwardine Formation (Ludlow Series, upper Silurian) of the Anglo-Welsh basin. In shelf areas, original patchiness of level-bottom benthic epifauna, opportunistic species, and wide faunal belts characterize the storm-influenced subtidal environments. Monospecific assemblages suggest high environmental stress.

• Read more about Faunal and facies dynamics in the Upper Silurian of the Anglo-Welsh basin

Scanning electron microscope observations were made of more than one thousand specimens of acolumellate semitectate pollen, all of which originate from the borehole Mersa Matruh 1, North-West Desert, Egypt. The detail observed enables thirteen forms to be distinguished from this set of specimens. It is suggested that the acolumellate pollen group should be separated from affinities with described columellate taxa. The newly described variety in this group gives it improved stratigraphic value.

• Read more about Early Cretaceous acolumellate semitectate pollen from Egypt

The adaptive morphology and mode of life of a large bizarre pectinid, Fortipecten takahashii (Yokoyama) from the Pliocene of north Japan and Sakhalin, were examined mainly from the standpoint of relative growth. In spite of its similarity to some extant species of Patinopecten in the early growth stage, Gryphaea-like and unusually heavy valves are formed after the middle stage by a drastic change of growth pattern.

• Read more about Fortipecten takahashii, a reclining pectinid from the Pliocene of north Japan

Antarctic wood-boring bivalves are described from the Kotick Point Formation, Gustav Group (Early Cretaceous) and the Marambio Group (Late Cretaceous) of the James Ross Island group, and from the Early Cretaceous part of the Fossil Bluff Formation of eastern Alexander Island. They are identified as the pholadid genera Opertochasma, Teredina, Turnus, and Xylophagella. All but Turnus are recorded here from the Antarctic for the first time. The following new species are described: Opertochasma psyche, Teredina jeffersoni, Turnus kotickensis, and Xylophagella truncata.

• Read more about Cretaceous wood-boring bivalves from Western Antarctica with a review of the Mesozoic Pholadidae

To understand the mode of life of Eubostrychoceras muramotoi Matsumoto, 1967, and some other heteromorph ammonoids from the Upper Cretaceous of Hokkaido, Japan, their life orientation and growth patterns were restored using a hydrostatic model and differential geometry. The adequacy of these restorations was tested using the obliquity of ribs and its change during ontogeny. Rib obliquity parallels the aperture at every growth stage and corresponds well to the inferred changes of life orientation.

• Read more about Changes in life orientation during the ontogeny of some heteromorph ammonoids

Middle Jurassic ammonites of China are known only from Tibet. Eighteen localities are described, some new. Only Lower Bajocian and Lower-Middle Callovian are established, whereas the other Middle Jurassic stages or substages are usually represented by hiati or non-marine facies.

• Read more about Middle Jurassic ammonites of Tibet and the age of the lower Spiti Shales

The ichnogenus Undichna Andersen, 1976, consisting of wavy horizontal grooves representing the drag marks of fish fins, is reported from the lacustrine Bude Formation. Two of the three species erected by Anderson are present. Two additional types of trail share strong similarities with Anderson's established species, but exhibit new features which warrant the erection of two new species, namely U. britannica and U. consulca. The new features necessitate modification of the original generic diagnosis.U.

• Read more about Fish trails in the Upper Carboniferous of south-west England