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Biomineralized tissues are chemically altered after death, and this diagenetic alteration can obscure original biological chemical features or provide new chemical information about the depositional environment. To use the chemistry of fossil biominerals to reconstruct biological, environmental or taphonomic information, a solid appreciation of biomineralization, mineral diagenesis and biomineral–water interaction is needed.

• Read more about Chemical taphonomy of biomineralized tissues

Like many other important evolutionary transitions, our knowledge of the origin of vertebrates is limited to windows of exceptional preservation of soft-bodied fossils. Unfortunately, these fossils are rare and have been subjected to complex taphonomic filters including decay, collapse and distortion. To maximize our ability to utilize these crucial fossils to reconstruct the timing and sequence of evolutionary events, we are in the need of a robust taphonomic framework with in which to interpret them.

• Read more about Atlas of vertebrate decay: a visual and taphonomic guide to fossil interpretation

• Read more about Finichnus, a new name for the ichnogenus Leptichnus Taylor, Wilson and Bromley, 1999, preoccupied by Leptichnus Simroth, 1896 (Mollusca, Gastropoda)

This study examines the development of the delthyrium, pseudodeltidium and interarea, their growth during the early juvenile stages of ontogeny and the extrapolation of morphology from adult shells to the probable juvenile state. Examination of the development and shell microstructure of the cardinalia of early juvenile thecideide brachiopod ventral valves from Jurassic, Cretaceous and Holocene specimens suggests that the delthyrium develops early in ontogeny and that the initial development of the pseudodeltidium precedes that of the interarea.

• Read more about The development and shell microstructure of the pseudodeltidium and interarea in thecideide brachiopods

A large number of complete specimens together with numerous disarticulated sclerites of the eodiscinid trilobite Sinodiscus changyangensis Zhang inZhou et al., 1977 have been collected from the lower Cambrian Shuijingtuo Formation in Changyang, Hubei Province, South China. An ontogenetic series is established based on the immature and mature exoskeletons including the previously unknown protaspides and meraspides, in particular. No further substages can be differentiated in the protaspid specimens herein.

• Read more about Morphology and ontogeny of the eodiscoid trilobite Sinodiscus changyangensis from the lower Cambrian of South China

The edrioasteroid, Aragocystites belli gen. nov. sp. nov. from the middle Cambrian Murero Formation of Spain, is described based on a small number of very well-preserved specimens. Important anatomical characteristics include star-shaped and pseudoclavate theca, rare or absent epispires, well-developed interradially positioned oral plates and several unorganized cover plates associated with each widely exposed flooring plate.

• Read more about Morphology and phylogenetic interpretation of a new Cambrian edrioasteroid (Echinodermata) from Spain

A new cinctan echinoderm, Graciacystis ambigua gen. et sp. nov. from Cambrian Series 3 rocks of Spain, is described based on more than 100 articulated specimens that range from 6 to 14.5 mm in thecal length. This material shows that Graciacystis ambigua, while plastic in thecal shape, is highly conservative in its thecal construction, with a fixed number of marginal plates and very limited addition of plates in the stele and ventral membrane through ontogeny.

• Read more about The ontogeny of cinctans (stem-group Echinodermata) as revealed by a new genus, Graciacystis, from the middle Cambrian of Spain

The mid-Cretaceous bivalve Goshoraia Tamura, 1977, endemic to Japan, is an early example of shallow-marine siphonate bivalves of the family Veneridae Rafinesque, 1815. Three species, including one new, are here described: Goshoraia minor Tashiro and Kozai, 1989 (Aptian), G. crenulata (Matsumoto, 1938; Albian–lower Cenomanian) and G. maedai sp. nov. (middle to ?upper Cenomanian).

• Read more about Palaeoecology of the mid-Cretaceous siphonate bivalve genus Goshoraia(Mollusca, Veneridae) from Japan

Late Ordovician rhynchonelliformean brachiopods, typical of the North American Red River fauna, are found sporadically in the Børglum River Formation of the Centrum Sø area, Kronprins Christian Land, eastern North Greenland. The geographical distribution of this characteristic brachiopod fauna is thus extended to the easternmost extremity of the Laurentian craton. The assemblage compares specifically with the Hiscobeccus brachiopod fauna, based on key taxa such as notably Hiscobeccus gigas (Wang, 1949), and indicates a late Katian age for this part of the succession.

• Read more about Late Ordovician brachiopods from eastern North Greenland: equatorial offshore migration of the Red River fauna

The thalloid carbonaceous fossil Nematothallus Lang, 1937, has been widely interpreted as an early Palaeozoic land-plant, despite the absence of a convincing modern analogue. Exceptionally well-preserved nematophyte cuticle from the Late Silurian Burgsvik Sandstone Formation, Gotland provides additional insight into the organism’s anatomy, phylogenetic affiliations and ecology. Because this material exhibits additional characters not present in the type material we assign it to Nematothallopsis gotlandii gen. et sp. nov.

• Read more about A new view on Nematothallus: coralline red algae from the Silurian of Gotland