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Cyclopterid leaves were borne on the same Late Carboniferous medullosalean plants that bore the pinnate fronds currently known as Laveineopteris. They were morphologically and anatomically different from the pinnate foliage, and presumably were also physiologically different. The cyclopterids are here interpreted as having been shade leaves and the pinnate foliage sun leaves. The juvenile Laveineopteris plant probably consisted of a monopole sapling bearing only cyclopterid leaves, which optimized growth in canopy shade conditions.

• Read more about Ecology and growth habit of Laveineopteris: a gymnosperm from the Late Carboniferous tropical rain forests

A new jawless vertebrate, Achanarella trewini gen. et sp. nov., is described from some recently discovered, relatively well-preserved specimens from the Achanarras fish bed at Achanarras Quarry, northern Scotland. The Achanarras fish bed is of Middle Devonian (Eifelian) age. Achanarella is a torpedo-shaped jawless vertebrate with a strongly hypocercal tail and well-developed anal fin. It has at least 13 branchial openings with possibly more than 20. It is scaleless.

• Read more about A new naked jawless vertebrate from the Middle Devonian of Scotland

Eifelian (Middle Devonian) ammonoids of the Pinacitinae Hyatt, 1900 (Exopinacites, Pinacites)with preserved shell structures from the eastern Anti-Atlas (Morocco) have revealed unusual morphological features. The Pinacitinae belong to the earliest ammonoids which closed their umbilici. As an approach to an interpretation of these structures, the representatives of the subfamily Pinacitinae (Exopinacites singularis, Pinacites jugleri, P. eminens) are compared with other ammonoids, e.g.

• Read more about Occluded umbilicus in the Pinacitinae (Devonian) and its palaeoecological implications

A new carcinosomatid eurypterid, Rhinocarcinosoma dosonensis sp. nov., and Hughmilleria sp., are described from the Do Son Formation of the Do Son Peninsula, northern Vietnam. R. dosonensis is characterized by podomere 7 of prosomal appendage VI produced into an anterodistal spine, a metastoma with a cordate posterior margin, and an indented opisthosomal differentiation (i.e. preabdomen-postabdomen margin is concave).

• Read more about A new carcinosomatid eurypterid from the Upper Silurian of northern Vietnam

The skeletal structure of Coletta seca, a small procolophonoid reptile from the Lower Triassic Lystrosaurus Assemblage Zone of South Africa, is reconsidered in light of descriptions of other procolophonoids. The presence of a single row of relatively large, fang-like vomerine teeth, identified originally as the single autapomorphy of this taxon, is reinterpreted as two rows of parachoanal vomerine teeth that are similar in organization to those of coeval procolophonids from Russia.

• Read more about A reappraisal of Coletta seca, a basal procolophonoid reptile from the Lower Triassic of South Africa

The shell structure of the Lower Cambrian Mickwitzia, a bilaterally symmetrical bivalve hitherto doubtfully assigned to the Brachiopoda, confirms that the genus shares characters with linguliform brachiopods. The columnar lamination of its organophosphatic shell is homologous with that characterizing acrotretides. The shell, however, is also pervaded by striated apatitic tubes indistinguishable from those permeating the sclerites of the problematic organophosphatic, laminar-shelled Micrina which is close to Halkieria.

• Read more about A stem group brachiopod from the Lower Cambrian: support for a Micrina ancestry

The stratiform laminae of Micrina sclerites originally consisted of rheomorphic successions of monolayers of micrometric-sized, apatitic tablets, presumably interleaved with chitin and glycosaminoglycans (GAGs). Paired laminae enclose slot-like chambers swelling into lobes distally that originally contained GAGs and deposits of spherulitic and prismatic apatite. The laminae are pervaded by apatitic tubes, apparently secreted by microvillous setoblasts and containing, at the surface, chitinous setae.

• Read more about Shell structure and inferred growth, functions and affinities of the sclerites of the problematic Micrina

• Read more about Basal dinosauriform remains from Britain and the diagnosis of the Dinosauria: corrigendum

A new monachine phocid pinniped assemblage from the north-central coast of Chile is described. The material was recovered from a marine bonebed of the Bahia Inglesa Formation which, based on macro- and microfossil evidence, is probably Late Miocene-Early Pliocene in age. At least two genera, Acrophoca and Piscophoca (both originally described from the Pisco Formation of Peru), are present.

• Read more about Fossil seals from late Neogene deposits in South America: a new pinniped (Carnivora, Mammalia) assemblage from Chile

Scales of nine thelodont taxa are described from the Red Bay Group of Spitsbergen, also characterized by its assemblage of other typical Early Devonian vertebrates. The four thelodont-bearing horizons of the lower Fraenkelryggen Formation yield typical Lochkovian thelodont assemblages, containing Boreania minima, Canonia grossi, Nikolivia depressa sp. nov., Nikolivia elongata, Nikolivia gutta and Turinia pagei. One horizon from the younger Ben Nevis Formation has a similar thelodont assemblage, except for two new taxa; Apalolepis angelica sp. nov. and Turinia barentsia sp. nov.

• Read more about Thelodont scales from the Lower Devonian Red Bay Group, Spitsbergen