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Tropidaster pectinatus is redescribed based on the original collection from Lower Jurassic (Pliensbachian) strata of England. It is the only recognized member of the Tropidasteridae, which is assigned to the Order Velatida in an intermediate phylogenetic position between the extant families Solasteridae, the earliest known representative of which is from Middle Jurassic (Bathonian) strata and considered primitive in the order, and the Korethrasteridae, known only from Holocene species.

• Read more about Redescription and interpretation of the asteroid species Tropidaster pectinatus from the Jurassic of England

The rare Bohemian genus Celaeceras, a primitive auguritid ammonoid with a rather bizarre suture, has been found in late Emsian strata (Upper Zlichovian) in the Palentine Domain of northern Spain. This occurrence provides the first precise age for the genus, and considerably extends its palaeogeographical range in the Devonian of northern Gondwanaland.

• Read more about An occurrence of the auguritid ammonoid Celaeceras in the Lower Devonian of northern Spain

Most vermetids are cemented to hard substrates, and can extend the shell aperture high above the substrate. The shell can be bent sharply around obstacles, and internal septa allow it to become much longer than the soft parts. Several vermetids use these adaptations to live as facultative soft-bottom dwellers, but no species appears to be permanently adapted to this environment. In contrast, siliquariids are not cemented. Siliquaria lives embedded within sponges as a commensal or parasite, letting its exhalant current flow out of the shell and into the host sponge through a very long slit.

• Read more about Adaptations of vermetid and siliquariid gastropods

Latest Toarcian (Early Jurassic) strata crop out in southern Alaska, southern Yukon, British Columbia, south-western Alberta, and eastern Oregon. Work in the Queen Charlotte Islands, British Columbia has proved a relatively complete Toarcian sequence which has provided the basis for a North American Toarcian ammonite zonation. The Upper Toarcian Yakounensis Zone is characterized by a diverse ammonite fauna, previously assigned to the Middle Toarcian.

• Read more about Latest Toarcian ammonoids from the North American Cordillera

A vertebrate assemblage from the Cenomanian of Wadi Milk, northern Sudan, includes material of all three major groups of lissamphibian, namely frogs, salamanders and gymnophionans, of which the latter two groups are described in this work. The productive horizons in the Wadi Milk Formation are lacustrine and the vertebrates are represented by isolated elements. The salamander material is described as Kababisha humarensis gen. et sp. nov. and Kababisha sudanensis gen. et sp. nov. and is referred to the family Sirenidae.

• Read more about Sirenid salamanders and a gymnophionan amphibian from the Cretaceous of the Sudan

It is difficult to provide a monothetic diagnosis of a clitambonitidine brachiopod, as any important feature (chilidium, deltidium, spondylium, etc.) of a 'standard' genus such as Vellamo may be absent from another stock that is nevertheless a quite acceptable member of the suborder. Critical examination is made of the morphological structures, particularly those associated with the vital functions of maintaining position relative to the substrate and of feeding.

• Read more about A review of the morphological features affecting the classification of clitambonitidine brachiopods

Lithocodium aggregatum, an enigmatic micro-encruster widespread in Mesozoic shallow marine carbonates, was considered to be a codiacean alga but can now be identified from Upper Jurassic examples as loftusiid foraminifer (Order Lituolida, Superfamily Loftusiacea). The microgranular wall may also contain detrital quartz, a feature which excludes any codiacean affinity. The complex, alveolar though imperforate, wall structure is identical to that of other loftusiid foraminifers; the only difference is the encrusting life habit of Lithocodium.

• Read more about The Jurassic Lithocodium aggregatum-Troglotella incrustans foraminiferal consortium

The type material of Helminthopsis Heer, 1877 has been examined. The ichnospecies established by Heer (1877) are unsuitable for representing this ichnogenus. Helminthopsis magna (subsequently designated type ichnospecies by several authors) and Helminthopsis intermedia are specimens of Scolicia isp. de Quatrefages, 1849, while Helminthopsis labyrinthica is a three-dimensionally complex graphoglyptid quite unlike Helminthopsis auctt. and very similar to Spirocosmorhaphe helicoidea Seilacher, 1989.

• Read more about Re-evaluation of the ichnogenus Helminthopis – a new look at the type material

The authors discuss the large and diverse Upper Palaeozoic strophomenide (sensu lato) group of brachiopods, the Productida, the problems inherent in previous classifications and present a new classification with diagnoses down to subfamily and tribe levels. In describing productides it is useful to differentiate between the main corpus (new term) cavity and peripheral cavities. Study of the ways in which the two valves grew leads to more precise identification of the visceral and trail regions of the shell.

• Read more about A review and new classification of the brachiopod order Productida

The abnormal histology of a ?pathological Iguanodon (Dinosauria; Ornithischia) caudal vertebra centrum is described and comparisons made with normal iguanodontid histology. The abnormal bone exhibits rapidly generated radial growth patterns; in the cancellous zone, areas of primary bone predominate and ther is a distinctive contorted vascularity throughout. The similarities of the observed deformations to known mammalian pathologies such as local trauma, Paget's disease, haemangioma and vitamin deficiency are discussed.

• Read more about Abnormal histology in an Iguanodon caudal centrum from the Lower Cretaceous of the Isle of Wight