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The placoderm fauna of the late Famennian tetrapod‐bearing locality of Strud, Belgium, is studied on the basis of historical and newly collected material. It includes the previously described antiarch Grossilepis rikiki, the groenlandaspidid Turrisaspis strudensis sp. nov. and the actinolepidoideid Phyllolepis undulata. P. undulata is thoroughly described and joins the list of the valid Phyllolepis species confidently diagnosed.

• Read more about Characterization of the placoderm (Gnathostomata) assemblage from the tetrapod‐bearing locality of Strud (Belgium, upper Famennian)

A key question in palaeontology is whether the fossil record taken at face value is adequate to represent true patterns of diversity through time. Some methods of assessing data quality have depended on the commonly observed covariation of palaeodiversity and fossiliferous formation counts through time, based on the assumption that the count of formations containing fossils, to a greater or lesser extent, drives diversity; but what if diversity drives formations?

• Read more about Palaeodiversity and formation counts: redundancy or bias?

The proviverrines from the Ypresian (MP7–MP10) and Lutetian (MP11–MP14) are represented mainly by species recorded in the northern and central parts of Europe (Paris Basin, Belgian Basin, Germany, Switzerland). Here, we describe fossils from southern France: Saint‐Papoul (MP8 + 9; Aude) and Aigues‐Vives 2 (?MP13; Aude). One dentary with secant molars from Saint‐Papoul represents a new genus and species, Preregidens langebadrae. This taxon is possibly present in Avenay (France), the MP8 + 9 reference locality.

• Read more about New fossil Hyaenodonta (Mammalia, Placentalia) from the Ypresian and Lutetian of France and the evolution of the Proviverrinae in southern Europe

• Read more about The oldest compelling evidence for sponges is still early Cambrian in age – reply to Love and Summons (2015)

The cranial anatomy of the iconic early tetrapod Eusthenopteron foordi is probably the best understood of all fossil fishes. In contrast, the anatomy of the lower jaw – crucial for both phylogenetics and biomechanical analyses – has been only superficially described. Computed tomography data of three Eusthenopteron skulls were segmented using visualization software to digitally separate bone from matrix and individual bones from each other.

• Read more about Computed tomography, anatomical description and three‐dimensional reconstruction of the lower jaw of Eusthenopteron foordi Whiteaves, 1881 from the Upper Devonian of Canada

Due to inadequate preservation, pterobranchs are often difficult to identify in the fossil record, and a better understanding of preservational modes and diagenetic and metamorphic effects is needed for their recognition. Pterobranch hemichordates are common in Cambrian Stage 5 and younger sedimentary rocks, but are frequently overlooked. Often, pterobranch hemichordate colonies have been considered to be algal remains or hydroids.

• Read more about Graptolite (Hemichordata, Pterobranchia) preservation and identification in the Cambrian Series 3

Occupying the role of primary consumer and having an early–middle Permian age range, caseids (Caseasauria, Synapsida) are fundamental to the interpretation of the early history of terrestrial vertebrate ecosystems. Despite this importance, no comprehensive, species‐level phylogenetic study of Caseidae has yet been performed. Herein, we present a phylogenetic analysis of the group, using gap weighting to include poorly known taxa. Besides the description and comments on the resultant topologies, some more general issues concerning cladistic methodologies are briefly addressed.

• Read more about Cladistic analysis of Caseidae (Caseasauria, Synapsida): using the gap‐weighting method to include taxa based on incomplete specimens

Extant aplacophorans, a group of shell‐less vermiform molluscs, respire through appendages within or projecting from a posterior cavity. Respiratory structures differ between the subclasses Caudofoveata (ctenidia within the cavity) and Solenogastres (folds of the mantle itself). Acaenoplax hayae, a Silurian vermiform mollusc from the Herefordshire Lagerstätte, England, exhibits characteristics of both these groups.

• Read more about A novel respiratory architecture in the Silurian mollusc Acaenoplax

The Ordovician and Silurian periods were times of major geological activity as regards palaeogeography, volcanism and climate change, the last of these evidenced by a series of cooling episodes and glaciations that climaxed in the Hirnantian (Late Ordovician). The presence of cryptospores in the Darriwilian (Middle Ordovician) marked the advent of higher plants on land. A critical survey of direct (mega‐ and microfossils) and some indirect evidence in succeeding rocks indicates the presence of algae, Bacteria, Cyanobacteria, Fungi, probable lichens, cryptophytes and basal tracheophytes.

• Read more about Could land‐based early photosynthesizing ecosystems have bioengineered the planet in mid‐Palaeozoic times?

We present the rationale for a cross‐disciplinary investigation addressing the ‘Devonian plant hypothesis’ which proposes that the evolutionary appearance of trees with deep, complex rooting systems represents one of the major biotic feedbacks on geochemical carbon cycling during the Phanerozoic. According to this hypothesis, trees have dramatically enhanced mineral weathering driving an increased flux of Ca²⁺ to the oceans and, ultimately, a 90% decline in atmospheric CO₂ levels through the Palaeozoic.

• Read more about Investigating Devonian trees as geo‐engineers of past climates: linking palaeosols to palaeobotany and experimental geobiology