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Seven craniide brachiopod genera are described from the Silurian (Wenlock–Ludlow) of Gotland, including one new genus and five new species. The new genus and species Thulecrania septicostata is unique among Silurian craniides as it possesses solid spines. The new species Lepidocrania multilamellosa is the first Silurian record of this poorly known Permian genus.

• Read more about Silurian craniide brachiopods from Gotland

Knowledge of the Early Cretaceous ammonoids of the NW-Himalayas was poor until recent discoveries. Intense sampling from the Giumal Formation exposed near the village of Chikkim (Spiti Valley, Himachal Pradesh, India) led to the recognition of a new Early Cretaceous ammonoid fauna. The succession consists of arenitic sandstone interbedded with shale that was deposited by turbidity currents on an unstable shelf in the Early Cretaceous. Ammonoids have been obtained only from sandstone beds in the lower one-third and close to the top of the c. 350-m-thick section.

• Read more about New ammonoid taxa from the Lower Cretaceous Giumal Formation of the Tethyan Himalaya (Northern India)

Two species of Anomalocaris co-occur in the Emu Bay Shale (Cambrian Series 2, Stage 4) at Big Gully, Kangaroo Island. Frontal appendages of Anomalocaris briggsi Nedin, 1995, are more common than those of Anomalocaris cf. canadensis Whiteaves, 1892, at a quarry inland of the wave-cut platform site from which these species were originally described.

• Read more about New anatomical information on Anomalocaris from the Cambrian Emu Bay Shale of South Australia and a reassessment of its inferred predatory habits

New silicified topotypic material of the Upper Ordovician Streptis undifera (Schmidt, 1858) from the stratotype of the Porkuni Regional Stage in Estonia provides important data on triplesiid morphology and ontogeny, which has substantial implications for our understanding of the affinity of this group of brachiopods. In particular, the new material shows that the early ontogeny of Streptis includes evidence for a cicatrix attachment and colleplax-like structure in the ventral valve.

• Read more about Morphology, ontogeny and affinities of the Hirnantian triplisiid brachiopod Streptis undifera from Baltoscandia

The morphological variation of stromatoporoids, which are solitary organisms, is partitioned into its presumably genetic and environmental components. Potentially heritable, environmentally mediated and residual components of morphological variability were estimated in a test set containing Devonian stromatoporoids of the genus Gerronostromaria from southern Poland using analysis of variance. The taxonomic importance of traditional morphometric features is limited, because they are dominated by the intra-skeletal component of variance.

• Read more about The limited value of traditional morphometric features in stromatoporoid taxonomy

Upper Serpukhovian to lower Bashkirian conodonts studied from the lower and middle part of the Barcaliente Formation type section (NW Spain) are not abundant, but the sedimentary record seems unusually well represented. The first occurrence of Declinognathodus bernesgae occurs more than 140 m below the first occurrence of D. inaequalis, the taxon of the D. noduliferus species group appearing in the bed of the Global Standard Stratotype-section and Point (GSSP) for the Mid-Carboniferous Boundary (Arrow Canyon, Nevada). P1 elements transitional between D. bernesgae and D.

• Read more about Early evolution of Declinognathodus close to the Mid-Carboniferous Boundary interval in the Barcaliente type section (Spain)

Elevated concentrations of an organic compound, 24-isopropylcholestane, found in the Precambrian Huqf Supergroup of Oman may provide the oldest known sponge ‘fossil’. This evidence is of critical importance for a properly balanced understanding of the origin of animals. Several different pelagophyte (Class Pelagophyceae part of the Stramenopiles within the Chromaveolata) algae are also capable of producing these exact compounds, and may similarly have done so in deep time.

• Read more about Questioning the evidence of organic compounds called sponge biomarkers

Despite an impressive radiation of more than 30 species in the wake of the end-Permian mass extinction, the taxonomic study ofSaurichthys has suffered from a lack of universally diagnostic features and a lack of tested quantitative schemes that can be applied to analyse interspecific morphological differences. In this study, we provide an initial quantitative framework for morphological evolution inSaurichthys by focusing on a single bone, the opercle and exploring patterns of interspecific variability in shape using outline-based geometric morphometrics and linear measurements.

• Read more about A quantitative evaluation of evolutionary patterns in opercle bone shape in Saurichthys (Actinopterygii: Saurichthyidae)

A sea urchin placed on the sea floor near an active brine seep was recovered after 13 years with detailed soft-tissue preservation. Growth of an amorphous calcium carbonate solid with small amounts of the mineral bassanite occurred on the spines and test. The solid also exhibits striations at both the macro- and microscopic scales that preserve the muscle texture of the sea urchin. Such soft-tissue replacement and mineralization could lead to exquisite fossilization.

• Read more about Experimentally observed soft-tissue preservation near a marine brine seep

Protoheliolites is an early heliolitine coral characterized by closely spaced corallites separated in places by sparse coenenchyme. Growth characteristics in the type species, P. norvegicus, are revealed by detailed analysis based on serial peels and thin sections of coralla from the uppermost Katian of north-western Estonia.

• Read more about Growth characteristics of Protoheliolites norvegicus (Tabulata; Upper Ordovician; Estonia)