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The acritarchs and prasinophyte algae from the Upper Bringewood, Lower Leintwardine, Upper Leintwardine and Lower Whitcliffe formations of the Ludlow type area and surrounding regions are described. The following new taxa are proposed: Cymatiosphaera pumila sp. nov., Melikeriopalla pustula sp. nov., Cheleutochroa beechenbankensis sp. nov., Cymbosphaeridium molyneuxii sp. nov., Flammulasphaera bella gen. et sp. nov., Percultisphaera incompta sp. nov., Salopidium aldridgei sp. nov. and Umbellasphaeridium? wicanderi sp. nov.

• Read more about Upper Silurian microplankton of the Leintwardine Group, Ludlow Series, in the type Ludlow area and adjacent regions

The life orientation and mode of life of stylophorans are a subject of much ongoing debate. Examination of the ornamentation occurring both on the arm and theca in several cornutes and mitrates strongly supports the view that the life orientation was similar in all stylophorans and was 'flat-surface down'. The presence of an asymmetrical ornamentation adapted to hinder, or minimize, back slippage of the organism in all stylophorans gives strong support to their interpretation as mostly sessile organisms, feeding with the arm facing the current and the theca downstream.

• Read more about Functional morphology of stylophoran echinoderms

New terrestrial and freshwater arthropods are described from the Windyfield cherts, a suite of silicified sinters deposited 700m north-east of the Rhynie cherts and part of the same Early Devonian hot-spring complex. The diverse assemblage consists of Heterocrania rhyniensis (Hirst and Maulik, 1926a), here recognized as a euthycarcinoid; scutigeromorph centipede material assigned to Crussolum sp.; the crustacean Lepidocaris; trigonotarbid arachnids; a new arthropod of myriapod affinities named Leverhulmia mariae gen. et sp.

• Read more about An Early Devonian arthropod fauna from the Windyfield cherts, Aberdeenshire, Scotland

The Chengjiang Lagerstatte in the Lower Cambrian of South China yields a small, larva-like arthropod, which was considered to be a protaspis of naraoiids by many authors. The discovery of a large number of well-preserved specimens from many new localities has allowed the original study to be revised. The relatively large size, stable morphology and unusual structure of the appendages indicate that these specimens represent adults of a new arthropod, Primicaris larvaformis. The larva-like outline is considered to have arisen by the heterochronic process of progenesis.

• Read more about Reconsideration of the supposed naraoiid larva from the Early Cambrian Chengjiang Lagerstätte, South China

Sphenobaiera ikorfatensis (Seward) Florin from the Lower Cretaceous Huolinhe Formation in the Huolinhe coal-mining area, eastern Inner Mongolia, China, is identified, described and figured. Comparison with the type material of Sphenobaiera ikorfatensis (Seward) Florin from West Greenland confirms its identity. About 20 Chinese leaf specimens are known with well preserved cuticle which is closely similar to the Greenland leaves but more papillate.

• Read more about Sphenobaiera ikorfatensis (Seward) Florin from the Lower Cretaceous of Huolinhe, eastern Inner Mongolia, China

Protaspid morphologies of Leiostegium sp. aff. L. formosum from the Lower Ordovician Garden City Formation, western United States strongly support the inclusion of the Leiostegiina in the order Corynexochida. A similar metaprotaspid morphotype is present in the three suborders of the Corynexochida, the Corynexochina, Leiostegiina, and Illaenina, supporting their corynexochid membership.

• Read more about Protaspides of Leiostegium and their implications for membership of the order Corynexochida

Laveineopteris is emended to become a morphogenus for the vegetative parts of certain medullosalean pteridosperms that grew in the Westphalian (Late Carboniferous) tropical rainforests. The plant bore pinnate foliage as sun leaves and entire orbicular leaves (cyclopterids) as shade leaves. The cyclopterids were attached to the axis of the saplings and epiphyllously to the lower parts of the pinnate fronds. Species recognition is mainly by the macro-morphology of the pinnate fronds.

• Read more about Systematics of the Late Carboniferous medullosalean pteridosperm Laveineopteris and its associated Cyclopteris leaves

Use of the genus Sphenobaiera Florin for deeply divided ginkgoalean leaves lacking a petiole is discussed. The type material of the species Sphenobaiera ikorfatensis (Seward) Florin from the Lower Cretaceous at Ikorfat in West Greenland is diagnosed, redescribed and the lectotype designated. The cuticle, which is described and figured in detail for the first time, shows the leaf to be amphistomatic and allows previous identifications of Sphenobaiera ikorfatensis in Lower Cretaceous floras from Siberia and China to be confirmed.

• Read more about The lectotype of Sphenobaiera ikorfatensis (Seward) Florin, a ginkgophyte from the Lower Cretaceous of western Greenland

Ammonites of the south-west German Posidonia Shale (Early Toarcian) are occasionally overgrown by bivalves, brachiopods or serpulids. Attachment to both sides of the conchs in some specimens suggests attachment during the ammonite's lifetime, with a pseudoplanktic mode of life for the epizoans. However, dense overgrowth restricted to the upper surface of some ammonite shells indicates post-mortem colonization. Our study shows that apart from oxygen supply as a main factor controlling benthic colonization, substrate consistency also played an important part.

• Read more about Overgrowth on ammonite conchs: environmental implications for the Lower Toarcian Posidonia Shale

The new species Acdestis maddeni is described based on the most complete skull of a palaeothentid marsupial known so far. The skull preserves most of the upper dentition and of the ear region, the latter an anatomical region previously unknown in this extinct family. A right maxillary fragment including C-M2 also belongs to the new species. The specimens come from the middle Miocene localities of Rosario and Quebrada Honda in southernmost Bolivia.

• Read more about New palaeothentid marsupial from the middle Miocene of Bolivia