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Construction work of the Highway A65 led the top of the Burdigalian ‘Molasses de l'Armagnac’ Formation to outcrop in two close localities near the town of Bazas and Marimbault, situated on the western edge of the Aquitaine Basin, France. From this formation, a rich fossil assemblage has been recovered and includes both marine and terrestrial fossil remains which offered the opportunity to reconstruct both seawater and terrestrial air temperatures at a regional scale during the Burdigalian. For this purpose, two sets of fossil samples representative of the whole assemblage have been selected for each locality. They include teeth and bones of sharks, fish, rays, reptiles and mammals, as well as tests of sea urchins and shells of bivalves. First, we performed rare earth element (REE) analyses of 53 apatite samples from both localities in order to characterize the diagenetic history of the assemblage. We then analysed the oxygen isotope composition of 49 biogenic apatite phosphate samples and 6 biogenic carbonate samples representing both marine and terrestrial organisms. Using published isotopic fractionation equations, both seawater and terrestrial air temperatures were reconstructed. Calculated seawater temperatures using phosphate and carbonate isotopic thermometers are + 23 ± 4 °C and + 25 ± 1 °C respectively for the locality of Mendouillet (Bazas) and + 24 ± 4 °C and + 26 ± 1 °C respectively for the locality of Monbalon-Miron (Marimbault). Calculated terrestrial air temperatures are + 18 ± 2 °C for the locality of Mendouillet and + 17 ± 2 °C for the locality of Monbalon-Miron. These regional temperatures are in good agreement with seawater and terrestrial temperatures calculated for other European localities of contemporaneous periods. These results also fit the global climatic context of the Mid-Miocene Climatic Optimum starting at the end of the Burdigalian. Even though the global climatic conditions were warmer than today during the end of the Burdigalian, calculated continental and seawater thermal gradient at mid-latitude appear to have been comparable to present-day ones. [ABSTRACT FROM AUTHOR]

The first fossil echinoids are recorded from the Cayman Islands. A regular echinoid, Arbacia? sp., the spatangoids Brissus sp. cf. B. oblongus Wright and Schizaster sp. cf. S. americanus (Clark), and the clypeasteroid Clypeaster sp. are from the Middle Miocene Cayman Formation. Test fragments of the mellitid clypeasteroid, Leodia sexiesperforata (Leske), are from the Late Pleistocene Ironshore Formation. Miocene echinoids are preserved as (mainly internal) moulds; hence, all species are left in open nomenclature because of uncertainties regarding test architecture. All Miocene taxa are recorded from single specimens apart from the 27 assigned to Brissus. Schizaster sp. cf. S. americanus (Clark) is compared to a species from the Oligocene of the south-east USA. Brissus sp. cf. B. oblongus is close in gross morphology to a taxon from the Miocene of Malta. Leodia sexiesperforata is identified from fragments with confidence, being the only extant Antillean sand dollar with elongate ambulacral petals that is limited to carbonate substrates. The Miocene echinoids of Grand Cayman, although of limited diversity, are mainly comprised of genera common in comparable mid-Cenozoic carbonate environments. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The ecologically significant shift in developmental strategy from planktotrophic (feeding) to lecithotrophic (nonfeeding) development in the sea urchin genus Heliocidaris is one of the most comprehensively studied life history transitions in any animal. Although the evolution of lecithotrophy involved substantial changes to larval development and morphology, it is not known to what extent changes in gene expression underlie the developmental differences between species, nor do we understand how these changes evolved within the context of the well-defined gene regulatory network (GRN) underlying sea urchin development. To address these questions, we used RNA-seq to measure expression dynamics across development in three species: the lecithotroph Heliocidaris erythrogramma, the closely related planktotroph H. tuberculata, and an outgroup planktotroph Lytechinus variegatus. Using well-established statistical methods, we developed a novel framework for identifying, quantifying, and polarizing evolutionary changes in gene expression profiles across the transcriptome and within the GRN. We found that major changes in gene expression profiles were more numerous during the evolution of lecithotrophy than during the persistence of planktotrophy, and that genes with derived expression profiles in the lecithotroph displayed specific characteristics as a group that are consistent with the dramatically altered developmental program in this species. Compared to the transcriptome, changes in gene expression profiles within the GRN were even more pronounced in the lecithotroph. We found evidence for conservation and likely divergence of particular GRN regulatory interactions in the lecithotroph, as well as significant changes in the expression of genes with known roles in larval skeletogenesis. We further use coexpression analysis to identify genes of unknown function that may contribute to both conserved and derived developmental traits between species. Collectively, our results indicate that distinct evolutionary processes operate on gene expression during periods of life history conservation and periods of life history divergence, and that this contrast is even more pronounced within the GRN than across the transcriptome as a whole. [ABSTRACT FROM AUTHOR]

This dataset inventories occurrence records of fossil echinoid specimens collected in the Calcaires à Spatangues Formation (CSF) that crops out in the southeast of the Paris Basin (France), and is dated from the Acanthodiscus radiatus chronozone (ca. 132 Ma, early Hauterivian, Early Cretaceous). Fossil richness and abundance of the CSF has attracted the attention of palaeontologists since the middle of the nineteenth century. This dataset compiles occurrence data (referenced by locality names and geographic coordinates with decimal numbers) of fossil echinoids both collated from the literature published over a century and a half, and completed by data from collection specimens. The dataset also gives information on taxonomy (from species to order and higher taxonomic levels), which has been checked for reliability and consistency. It compiles a total of 628 georeferenced occurrence data of 26 echinoid species represented by 22 genera, 14 families, and 9 orders. [ABSTRACT FROM AUTHOR]

The article discusses a report of the cidaroid echinoid remains in Bajocian-Bathonian vertebrate regurgitates from southern Poland. It elaborates the findings and tackles its broader significance for the ecology and evolution of echinoids. It also provides a source of data for the reconstruction of food webs in the fossil record and is important as evidence for the role of predation in echinoderm evolution.

Abstract: A spatangoid-produced ichnofabric is described from the Miocene Bateig Limestone, SE Spain. This ichnofabric is characterized by the dominant presence of large meniscate burrows (Bichordites) produced by irregular echinoids. This constitutes an unusual mode of occurrence for spatangoid bioturbation, as their traces are most typically preserved in bases and tops of sandstone event beds. In fact, despite their important role as burrowers in modern settings (that can be extended back to the Early Cretaceous based on their body fossil record), spatangoid trace fossils (Scolicia and Bichordites) are comparatively rare. Several factors play an important role in their preservation: mechanism of burrowing, sediment characteristics, early diagenesis and presence/absence of deep-tier burrowers. Spatangoid-produced ichnofabrics, such as those from the Bateig Limestone, characterize depositional settings with intermittent deposition of event beds where there is an absence of deeper-tier bioturbation. [Copyright &y& Elsevier]

Abstract: The classification of the Paris basin Bajocian–Oxfordian species of the genus Nucleolites is revised. A classic point of view, until now used by authors and mainly based on the general morphology of the test, is first developed. Then, this last is modified with new architectural data, which refer to the extraxial–axial theory concerning the structure of the apical system as well as the presence of supplementary and catenal plates. These architectural data are first used facing the general morphology of the test. Such approach leads to a new point of view for the classification of the species of the genus Nucleolites. The systematics is particularly significantly simplified. The deduced and proposed phylogenetic hypothesis shows that the genus Nucleolites is composed of two parallel lineages as soon as the beginning of the genus in the Bajocian: a group with a so-called “primitive” architecture, and a group with an “advanced” one. On and after the Late Callovian, the species with a primitive organisation give birth to advanced species, which continue in younger time. In this way, the genus Nucleolites may be paraphyletic since the Late Callovian onward. [Copyright &y& Elsevier]

Focuses on the history of preservation of echinoid fossils. Potential for the preservation of complete skeletons in the fossil record; Identification of disarticulated fossils; Morphological groups of echinoids.

Reports on the global analysis of a major marine invertebrate group, the sea urchins, which suffered 36 percent extinction at genus level in the late Maastrichtian age and continuing high levels of extinction in the Danian age. The indication that nutrient supply was a crucial factor in driving K/T-boundary extinctions, with selection more strongly focused on benthic adult than on larval planktotrophic stages.

Discusses the report by A.B. Smith and C.H. Jeffrey of a detailed study of the sea-urchin fossil record across the Cretaceous-Tertiary (K/T) boundary. The probe of the secondary causes by the end-Cretaceous mass extinction by searching for a global database of biological and geographical correlates; Problems that the two came across; The determination that the survival of genera restricted to one region depended strongly on the region.