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Despite their strong Raman scattering and importance in several applications in the geological and biological sciences, Mg-calcites have not been thoroughly investigated by Raman spectroscopy. In this study, we investigated whether Raman spectra of carbonates are sensitive to the structural and chemical changes occurring when Mg2+ substitutes Ca2+ in the calcite lattice. Different carbonate samples with variable Mg content (from 0 to 20 mol% MgCO3) of biological and inorganic origin have been first beamed under a Raman spectrometer and then analysed by scanning electron microscopy-energy dispersive spectrometer and electron microprobe analysis-wavelength dispersive spectrometer microprobes to determine their chemistry. The biological samples (foraminifers, algae, barnacles and echinoderms) were collected from areas situated at different latitudes and water temperature and saturation, factors affecting the chemical and isotopic composition of shells in marine organisms. The Raman band positions are directly linked to the amount of magnesium present in the calcite lattice, and all peaks of Mg-calcite spectra show a consistent and linear increase in Raman shifts according to their Mg content, which is a consequence of the decreased inter-atomic distances following the substitution of Ca2+ with the smaller Mg2+ ion. This study demonstrates that Raman spectroscopy provides an innovative work perspective in marine biology, provenance studies and oil exploration when estimates of mineralogical and chemical changes are the focus of the study. Raman spectroscopy is even more attractive – for the mentioned fields of research – than many other methods because of the non-destructive nature and its very short analytical time

Fourteen coralline algal species (Corallinales, Sporolithales) from Early Langhian (Lower Badenian) red-algal limestones of the Carpathian Foredeep (Czech Republic) are described: Sporolithon lvovicum (Maslov) Bassi et al., Lithothamnion roveretoi Airoldi, Lithothamnion moretii Lemoine, ?Lithothamnion sp. 1, ?Lithothamnion sp. 2, Mesophyllum alternans (Foslie) Cabioch & Mendoza, M. cf. erubescens (Foslie) Lemoine, M. cf. printzianum Woelkerling & Harvey, M. curtum Lemoine, Phymatolithon sp., Lithophyllum sp. 1, Lithophyllum sp. 2, Hydrolithon lemoinei (Miranda) Aguirre et al. and Spongites fruticulosa Kützing. The characters used in coralline algal species description and identification are summarized and discussed. Five characters newly used in fossil material are associated with the structure and fate of presumed tetrasporangial, gametangial and carposporangial conceptacles, with the shape, size and organization of roof cells, and with the position of the asexuate conceptacles relative to the surrounding thallus surface. Gametangial conceptacles of Phymatolithon and gametangial and carposporangial plants of Sporolithon lvovicum are described for the first time.

Fourteen coralline algal species (Corallinales, Sporolithales) from Early Langhian (Lower Badenian) red-algal limestones of the Carpathian Foredeep (Czech Republic) are described: Sporolithon lvovicum (Maslov) Bassi et al., Lithothamnion roveretoi Airoldi, Lithothamnion moretii Lemoine, ?Lithothamnion sp. 1, ?Lithothamnion sp. 2, Mesophyllum alternans (Foslie) Cabioch & Mendoza, M. cf. erubescens (Foslie) Lemoine, M. cf. printzianum Woelkerling & Harvey, M. curtum Lemoine, Phymatolithon sp., Lithophyllum sp. 1, Lithophyllum sp. 2, Hydrolithon lemoinei (Miranda) Aguirre et al. and Spongites fruticulosa Kützing. The characters used in coralline algal species description and identification are summarized and discussed. Five characters newly used in fossil material are associated with the structure and fate of presumed tetrasporangial, gametangial and carposporangial conceptacles, with the shape, size and organization of roof cells, and with the position of the asexuate conceptacles relative to the surrounding thallus surface. Gametangial conceptacles of Phymatolithon and gametangial and carposporangial plants of Sporolithon lvovicum are described for the first time.

Recent environmental changes in the Pak Phanang Bay (SW Gulf of Thailand) are investigated by means of mollusc assemblages. The present-day water depth within the bay slightly exceeds 2 m at low tide and the sea floor is almost entirely muddy, except for the outermost part of the embayment which is directly influenced by the longshore drift that is building the Laem Talumpuk sand spit. A multivariate analysis of the molluscan fauna recovered at 16 sampling stations within the bay delineates three thanatofacies and two biofacies. The Bay Mouth thanatofacies, including several infralittoral species, is distributed around the bay entrance; the Tidal Flat thanatofacies, characterized by few brackish and freshwater taxa, occurs in the inner part of the bay; the Channel thanatofacies includes a mixed fauna and is found along the long axis of the bay. All thanatofacies are not older than a few decades. The two biofacies are significantly less diverse than their dead counterparts, and are simply identified as Bay Mouth biofacies and Inner Bay biofacies. The faunal evolution, combined with bathymetric and sedimentological data, confirms that the embayment is undergoing a con finement process. The inner bay has evolved into an undifferentiated tidal flat hosting an oligospecific fauna. The confinement trend and the consequent siltation of the bay, mainly due to natural geomorphologic processes acting since centuries, are likely to have sped up in recent years by interaction with some human activities; among these, the deforestation in the upper Pak Phanang basin and the construction of Uthokaviphatprasit Watergate