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The fossil coralline flora of the Badenian bioclastic limestone outcropping in Northern Croatia is known under the name Litavac, shortened from "Lithothamnium Limestone". The name was given to indicate that unidentified coralline algae are the major component. In this first contribution to the knowledge of the coralline flora of the Litavac, Lithothamnion valens results to be the most common species, with an unattached, branched growth-form. Small rhodoliths composed of Phymatolithon calcareum and Mesophyllum roveretoi also occur. The Badenian benthic association is dominated by melobesioid corallines, thus it can be compared with the modern maërl facies of the Atlantic Ocean and Mediterranean Sea. Since L. valens still survives in the present-day Mediterranean, an analogy between the Badenian Litavac and the living L. valens facies of the Mediterranean is here suggested

Several campaigns at sea conducted in the Gulf of Thailand from 1996 to 2003 provided a wide database on mollusk soft-bottom assemblages. The shallow seafloor facing the Phetchaburi coastal plain was sampled at about 150 locations, while 25 were investigated in the Pak Phanang Bay (Nakhon Si Thammarat). All shells extracted from samples were identified to species level; this led to the publication of a suite of papers where a total of 695 taxa have been described and figured, thus obtaining the most detailed review on the marine mollusks of this area ever published. Among these species, 24 have been proposed as new to science. A brief analysis of shell material coming from 113 samples provides an overview of the taxonomic composition and diversity of the soft-bottom mollusk fauna in the Gulf. The 609 species recognized in thanatocoenoses of both areas belong to 111 families (47 of bivalves, 3 of scaphopods, 61 of gastropods); the most represented are, among bivalves, Galeommatidae (40 species), Tellinidae (32), Veneridae (23) and Arcidae (15); among gastropods, Turridae (54), Odostomiidae (45), Turbonillidae (36), Vitrinellidae (16), Triphoridae (17) and Epitoniidae (15). The number of species per sample spans from 5 to 254 in Phetchaburi, from 4 to 27 in Pak Phanang; the number of specimens per sample (with abundance values referred to a standard volume of 5 l) varies greatly from 3 to 16897 and from 10 to 2275 respectively. Conversely, mollusk live associations include only 115 species belonging to 49 families (25 of bivalves, 3 of scaphopods, 21 of gastropods); the best represented are, among bivalves, Tellinidae (10 species), Veneridae (8), Arcidae (7) and Mytilidae (7); among gastropods, Turridae (7), Vitrinellidae (3) and Columbellidae (3). The number of species per sample is comprised between 1 and 28 in Phetchaburi, 1 to 4 in Pak Phanang. The number of specimens per sample spans from 1 to 80 in Phetchaburi, from 1 to 395 in Pak Phanang. Sampled thanatocoenos

Fossil molluscan assemblages from 12 radiocarbon-dated short cores have been considered and integrated with information from archaeology, tectonics, and relative sea-level change in order to define the Holocene evolution of the Stagnone di Marsala, a sound along the western coast of Sicily that experienced at least 3000 years of human impact, since the Phoenician times. During the considered time span, we have no evidence of emersion, though the occurrence of a very restricted circulation is recorded at the base of very shallow cores dated 1240 ± 50 and 1560 ± 40 years BP. We hypothesise that the Phoenician road, now submerged, connecting the Island of Mozia with the Sicilian mainland, was critical in isolating a marshy environment along the southeastern coast of the Stagnone before about 1600 years BP. Our cores show that the molluscan association typical of the superficial muddy sand in sheltered areas (SVMC) has been always dominant at the basin scale, conformably to the present-day situation. Multivariate statistical analyses were performed on abundance data of molluscan associations resulting in four clusters that describe different aspects of the SVMC biocoenosis: the first characterised by the sediment-related SVMC species, and the other three associated with a more mud-rich sediment, with a prevalence of taxa related to the leaf stratum of Posidonia, Cymodocea, or to seaweeds. In contrast with the present-day situation, we record a past occurrence of Posidonietum in the northern basin at about 3600 years BP, corresponding to a period of more open circulation. This phenomenon was induced by channels, now closed by saltworks, that cut the present-day Isola Grande into islets.

Rhodoliths are nodular structures composed mainly of the superimposed thalli of calcareous red algae. Because their development is controlled by an array of ecological parameters, rhodoliths are a valuable source of palaeoenvironmental information. However, despite their common use in palaeoecological reconstructions, the stratigraphic significance of rhodolith accumulations seldom has been addressed in detail. In a study of Cenozoic rhodolith-bearing deposits from the North Island of New Zealand, rhodolithic units, usually of limited lateral extent, typically occur above major unconformities at the base of deepening upwards successions. Two types of transgressive rhodolith-bearing deposits may be distinguished on the basis of texture and rhodolith internal structure: (i) type A deposits are clast-supported rhodolithic rudstones containing abundant pebbles and cobbles reworked from the substrate, and are characterized by rhodoliths with a compact concentric to columnar internal structure and a high nucleus to algal cover ratio; (ii) type B deposits are rhodolithic floatstones with a matrix usually consisting of bryozoan fragments, benthic foraminifera and echinoid fragments or terrigenous silty fine sand. The rhodoliths of type B units usually have a loose internal framework with irregular to branched crusts. The two contrasting rhodolith-bearing units are interpreted as characteristic facies of transgressive systems tract deposits, analogous to shell concentrations formed under conditions of low net sedimentation. Type A deposits are correlated with relatively high-energy settings and/or narrow submerged palaeotopographic lows, whereas type B deposits are interpreted as forming in lower-energy settings. The association between transgression and development of rhodolithic facies is confirmed by observations of a modern rhodolith production site at Whangaparaoa Peninsula in North Island, where algal nodules grow above a ravinement surface cut during the Holocene seal

The study of the environmental evolution in coastal areas hit by December 2004 tsunami exhibits a great deal of interest in terms of both purely scientific research and environmental recovery and protection. The present project, started in 2006, aims to evaluate the variations occurred on coastal and shallow marine sediments and related populations of shelled benthic organisms; the study area comprises the intertidal and shallow infralittoral bottoms between Ban Khao Lak and Ban Chao Nam, along the Thai coast of the Andaman Sea. This area includes tracts heavily hit by the wave and other tracts where effects were moderate or locally absent. In this respect, an actuopaleontological approach - already applied to mollusks in several areas of the Gulf of Thailand - appears as a valid surrogate of the common yearly sampling of faunas. The comparison between recent thanatocoenoses, representing the benthic fauna settled before the tsunami event, and present populations will allow to define 1) the effect of the wave on soft-bottom communities, 2) the rates of recovery subsequently to the catastrophe and 3) the correspondence between pre-existing and newly settled communities. Moreover, the research aims to verify the possibility of building an evolution model of the pre-impact/impact/post-impact sequence, useful to better interpret layers recording very high energy conditions, that occur within sedimentary successions. In range of the project’s first phase, three scientific campaigns were carried out in 2006, in order to survey and sample the selected area. The analysis of samples is still in progress; nevertheless, some observations made contextually with the geomorphological coastal survey allowed to notice some evidences of the impact of the tsunami on intertidale and shallow infralittoral mollusks. Such evidences, besides supratidal shell and coral debris, mainly pertain to sessile species colonizing rocks, boulders and old coral blocks. Dense populations of oysters, f

Nell’inverno del 2005 sono stati effettuati dei campionamenti di sedimento lungo i fondali della costa di Ras Nosrani, circa 8 Km a nord di Sharm el Sheik (Sinai meridionale, Egitto). Tra il 2003 e il 2005, l’area costiera in corrispondenza del transetto studiato è stata interessata da un’intensa attività edilizia per la costruzione di nuovi insediamenti alberghieri, che ora sorgono a un centinaio di metri dalla spiaggia. La spiaggia emersa è delimitata da una beach-rock periodicamente coperta da sedimento, che si è formata al margine di un’ ampia piana di scogliera. Nel tratto di costa considerato, la cresta della scogliera marginale è posta ad una distanza di 50-150 m dalla battigia. Lungo un transetto di 70 metri perpendicolare alla linea di costa, a partire dai fondali che si raccordano alla cresta della scogliera con un ripido pendìo, sono stati raccolti sette campioni di circa 1 litro ciascuno, distribuiti nell’intervallo batimetrico tra 29,3 e 13,7 m (RN1 – RN7). Il sedimento associato mostra una granulometria generalmente decrescente verso il largo, con locali eccezioni dovute alla presenza di ciottoli e piccoli massi di origine corallina. Nelle tanatocenosi sono state riconosciute 179 specie di molluschi (gasteropodi, bivalvi e scafopodi) per un totale di 3093 individui estratti dal sedimento, identificati e conteggiati. Le famiglie più rappresentate risultano essere Pyramidellidae, Turridae, Costellariidae, Triphoridae, Rissoidae, Eulimidae, Fissurellidae e Trochidae tra i gasteropodi, mentre i bivalvi appartengono soprattutto a Lucinidae, Cardiidae e Tellinidae; le specie dominanti Rissoina sp., Paradrillia inconstans prunulum (Melvill & Standen, 1901), Mathilda gracillima Melvill & Standen, 1901, Pusia aethiopica (Jickell, 1874), Brachidontes variabilis (Krauss, 1848), Acar placata (Dillwyn, 1817) sono generalmente associate a sedimenti medio/grossolani. La ricchezza specifica tende ad aumentare avvicinandosi alla scogliera, con l’eccezione delle, During the 2005 winter, a sediment sampling was performed by SCUBA diving along the coastal sea floor of the Ras Nosrani coast, about 8 km north of Sharm El Sheik (southern Sinai, Egypt). From 2003 to 2005 the area was affected by intensive building activity for new hotels. In this area the crest of the fringing reef is separated from the beach by a 50-150 m wide reef-flat, bordered by a beach-rock. Seven sediment samples, each of about 1 l in volume, were collected along a 70 m profile normal to the coastline, across the depth range from 29,3 to 13,7 m (RN1 – RN7), from the fore-reef up to reef-slope. The sediment mean grain size decreases in the deepest samples, with the exception due to the occurrence of coral cobbles and small boulders at sample RN3. The molluscan shell association is composed of 179 species totalising 3093 specimens. The most common families are Pyramidellidae, Turridae, Costellariidae, Triphoridae, Rissoidae, Eulimidae, Fissurellidae and Trochidae among gastropods; Lucinidae, Cardiidae e Tellinidae among bivalves. The dominant species are commonly associated to medium/coarse sediment. Species richness is higher close to the reef, with the exception of RN3 and RN4, probably affected by substrate instability. A multivariate statistical analysis separates two groups of samples: a deep one (RN1 and RN2), with fine sediment and low molluscan diversity, and a shallow one with RN4 to RN7, with coarse sediment and high molluscan diversity. RN3 remains uncoupled, probably because of the mixed sediment texture.

Coastline migration significantly affects the evolution of marine and continental environments. Tracing sea-level changes that have occurred in the past can be achieved using evidence from marine benthic associations of fossil molluscs. This paper outlines a strategy for documenting recent molluscan benthic assemblages in order to detect abrupt or gradual variations in their depositional succession that could reflect changes in the land-sea relationship. Characteristics of molluscan fossil assemblages are reviewed and an example of such an analysis is offered from research conducted in Iskenderun Bay in the northeastern Mediterranean Sea. © 2007 Springer.

Some mid-Pleistocene carbonate build-ups from the marine terrace of Cutro show the uncommon, biologically-induced change of substrate that is implied in the definition of coralligène de plateau: from coarse, biogenic sediment to the solid framework. The build-ups grew over a basal rhodolithic layer mostly composed of Sporolithon ptychoides which was stabilized and transformed into a hard substrate by the binding activity and overgrowth of non-geniculate Corallinales (calcareous red algae). The build-ups are dominated by Titanoderma pustulatum, whose role in biogenic construction was previously underestimated, in association with Mesophyllum spp. and locally with Lithophyllum stictaeforme. Intergenicula of Amphiroa cryptarthrodia are common.

Recent anatomic observations of the types of Lithophyllum contii Mastrorilli, 1967, Lithophyllum embergeri Mastrorilli, 1968, Mesophyllum flexile Mastrorilli, 1968 and Mesophyllum rigidum Mastrorilli, 1968 urged their revision under modern taxonomic schemes. Lithophyllum contii Mastrorilli, 1967 is transferred to the subfamily Mastophoroideae and the new combination Neogoniolithon contii is proposed. L. giammarinoi, L. embergeri, M. flexile and M. rigidum are considered to be younger heterotypic synonyms of L. contii, originally established on the basis of anatomical details herein considered to be artefacts due to improper orientation of studied thalli. Each species is critically analysed on the basis of original Mastrorilli's collections (Genoa University, Dip.Te.Ris.) and additional material collected at the type localities.

Carbonate build-ups mainly constructed by encrusting coralline red algae are currently developing on Mediterranean soft bottoms, at depths ranging from 20 m to 160 m. They are usually referred to as ¿coralligène de plateau¿. Few fossil examples of these bioconstructions have been described in the literature and their evolution in the context of a stratigraphic cycle has never been modelled in detail. Cutro marine terrace (Calabria, southern Italy) preserves mid-Pleistocene deposits assigned to Marine Isotope Stage (MIS) 7 or MIS 9. Extensive algal build-ups representing the deepest unit of the succession occur in the outer and central portion of the terrace, interpreted as the most distal setting from the palaeo-shoreline. Two studied sections, Vrica and Telegrafo, showed that the solid biogenic framework grew over a basal rhodolithic layer, which was stabilized by the binding activity and overgrowth of nongeniculate Corallinales (calcareous red algae). Therefore, these bioconstructions represent a rare fossil example of corallige`ne de plateau. At the Telegrafo section, Titanoderma pustulatum has been identified as the major rhodolith component. The build-ups are dominated by T. pustulatum, associated mainly with Mesophyllum spp. and locally with Lithophyllum stictaeforme. Rhodalgal bioclastic deposits are found in lateral contact with the build-ups. The two facies developed together under a hydrodynamic regime where phases of sedimentation from storm-driven currents alternated with phases of calm conditions. They were deposited during a single stratigraphic cycle beginning with the generation of a ravinement surface during the transgressive systems tract (TST) and ending with the burial of the corallige`ne by wellsorted shoreface bioclastic sands. Optimal and extensive growth of the coralligène took place during the highstand systems tract (HST).

Cool to periglacial conditions, accompanied by a sea-level drop, are thought to result in an unchanged composition and ecological meaning of the rhodalgal carbonates, which occur frequently in the present-day, current-swept areas of the Mediterranean upper shelf. Form, internal structure and species composition of rhodoliths are believed to reflect the environmental conditions present in their biotope. To test these hypotheses, the relationship between rhodolith facies and sea-level rise was investigated in four cores recovered at the Pontian Islands (Tyrrhenian Sea) shelf break. The core basal intervals have been AMS radiocarbon dated, providing uncalibrated ages ranging from 10 040 +/- 50 years BP to 10 380 +/- 50 years BP. All four cores show a transition from basal rhodolith-rich, biodetritic, muddy-gravelly sand to rhodolith-barren, silty sand or sandy mud, along a deepening-upward succession. A facies of coral line-coated fragments of bryozoan colonies has been identified above the rhodolith facies as the deepest coralline growth form in all cores, before the final burial. Molluscan associations and rhodolith abundance, morphology and composition are ecologically compatible with the embedding sediment and testify the transition from the late Pleistocene circalittoral coastal detritic or shelf-edge detritic assemblages at the base of cores, up to the present-day bathyal muds. In the late Pleistocene and Holocene, as at present, the Pantine shelf was characterized by a low sedimentary input under moderate current action, fostering deep coralline growth.

Tetrasporangial male and female/carposporangial plants of a Mediterranean population of Spongites fruticulosus are described and compared with the type material of S. fruticulosus, Spongites racemosa and Spongites stalactitica. The three species were established by Kutzing on the basis of Mediterranean collections. The type material of S. fruticulosus is a rhodolith composed of a tetrasporangial plant possessing uniporate conceptacles, multistratose noncoaxial hypothallium and ovoid epithallial cells, growing on another unidentified sterile coralline with different vegetative characters. Spongites fruticulosus is lectotypified here with the tetrasporangial plant. The original material of S. racemosa represents a male plant of Neogoniolithon, here identified as Neogoniolithon racemosum (Kutzing) comb. nov. The type material of S. stalactitica is a rhodolith composed of a mixture of two species belonging to different genera: one, here selected as lectotype of S. stalactitica, is a female plant regarded as conspecific with S. fruticulosus. The second is the tetrasporophyte of a Neogoniolithon species. Detailed morphological-anatomical accounts of the species are presented, and their features are documented and discussed. The comparison between the Mediterranean types and new collections and the Australian population of S. fruticulosus revealed that Mediterranean plants have smaller sexual and asexual conceptacles and lack trichocytes. However, overlap in conceptacle dimensions and the rarity of trichocytes in the Australian specimens do not allow us to separate the Mediterranean and the Indo-Pacific populations into different species at this time.

The fluxes and budget of organic matter from the oligotrophic surface waters of the eastern Mediterranean to the deep waters are poorly known, and little information is available on past and present macrobenthic activity on the sea floor. Evidence of macrobenthic activity can be direct, through recovery of living organisms or their autochthonous skeletal remains, or indirect, through bioturbation and trace fossils. The evidence of biological activity in deep eastern Mediterranean sediments has been evaluated and compared through 210Pb profiles from box-cores and study of dredge samples from sites on Medina Rise (1374 m water depth), the Messina Abyssal Plain (4135 m) and several sites along the Mediterranean Ridge, SW and S of Crete (1783 to 3655 m). All these sites are remote from the continental shelves, so the biological benthic activity is expected to depend primarily on primary production from surface waters. The results show that present-day macrobenthos and trace fossils are generally scarce, especially at depths > 2500 m. This observation is supported by surface sediment 210Pb excess distributions that show a surface mixed layer (SML) 2500 m. The historical layer of some box-cores and the Pleistocene hardgrounds collected in the Cleft area (Mediterranean Ridge) do, however, record a macrobenthic activity that is apparently more intense than at present, which may be related to higher primary production of the Pleistocene glacial intervals. In contrast with most areas of the present-day deep eastern Mediterranean which depend on surface primary production based on photosynthesis, a relatively dense and diversified macrobenthic community based on chemosynthesis has been recognised at depths > 1100 m on the Napoli Dome mud volcano in the Olimpi area, and on the Kazan and other mud volcanoes in the Anaximander Mountains.

A newly discovered maerl bottom was sampled by grab at 45 m depth off the western coasts of Elba Island. Although the dominant, branched free-living corallines represent the maerl facires of the Coastal Detritic Biocoenosis (DC), the living molluscs are related to a different biocoenosis: the Coarse Sand and Fine Gravel under bottom currents (SGCF). In the molluscan shell assemblage, 2186 specimens belonging to 123 species have been analized on the basis of abundance, life habit, state of preservation, substrate preference and trophic behaviour. The evolution of the bottom has been traced, from terrigenous SGCF to biogenic DC in the recent past and toward SGCF again in the present. It is suggested that the maerl facies in the Mediterranean, at the boundary between DC and SGCF, would require a dynamic equilibrium between the two Biocoenoses and the ecological factors subtending them

Lithothamnion minervae is a crustose coralline alga recognized as a common rhodolith-forming species in the western Mediterranean basin. The species was erected in order to give a correct name and an unequivocal definition to the coralline misidentified for a long time as Lithothamnion fruticulosum. Details of the plant, such as the epithallial cells and the tetrasporangial or bisporangial and uniporate conceptacles are described on recently collected samples. It is shown that the two plants in the original collection of Millepora fasciculata belong to different taxa, and therefore a previous lectotypification (Woelkerling in Woelkerling & Lamy 1998) is superseded. The smaller of the two plants, which belongs to an undescribed species of Clathromorphum, is selected here as the new lectotype of M. fasciculata. The larger plant in the collection belongs to a species of Lithothamnion; it differs from L. minervae in having a smaller range of chamber diameters of multiporate conceptacles. embedded multiporate conceptacles filled with palisade cells and smaller perithallial cells.

New specimens of Subterraniphyllum thomasii Elliott collected from the Oligocene Molare Formation outcropping close to Alessandria (northern Italy) and studied in thin sections and by SEM showed that primary pit-connections, cell fusions, uniporate conceptacles and geniculate branches were present. These new observations collectively confirm the placement of S. thomasii within the geniculate Corallinaceae. Although S. thomasii share many diagnostic characters with the Corallinoideae, in particular with the tribe Corallineae (apical position of uniporate conceptacles, number of medullary cell layers) and some similarity with the Metagoniolithoideae (medullary cells gradually merging into the cortical cells) the lack of information on genicula and the observed details of insertion of branches do not allow to determine the suprageneric disposition of S. thomasii.

Airoldi (1930, 1932) described twenty-three fossil Corallinales (Rhodophyta) from the Oligocene of the Tertiary Piedmont Basin (NW Italy), containing thirteen new species. In this paper Archaeolithothamnium praeerithraeum Airoldi 1932 and Archaeolithothamnium statiellense Airoldi 1932 are re-documented and re-described. The features observable in the sporangial compartments allowed to attribute both species to the genus Sporolithon

A quantitative study of benthic foraminifera, sediment texture and composition from two cores was performed to unravel the environmental evolution of the Iskenderun Bay (eastern Turkey) in the Holocene. Core 29 (NE Iskenderun Bay) consists of clay and silt from the top of the core down to 35 cm with dominant bioclasts (coral Cladocora caespitosa) from 35 cm down to the bottom of the core. Core 92, located near an ancient Ceyhan River mouth (Yumurtalik), consists of sandy and silty sediment passing to homogeneous clay and silt at about 48 cm from the top. Several grab samples show very coarse biogenic detritus covered by a centimetric veneer of sandy silt and clay. Radiocarbon dating of corals, molluscs and algae from core 29 and five selected grab samples, the sediment and foraminiferal study indicate that at least three pulses of muddy sedimentation occurred in the bay. (1) An older pulse (about 3700 yrs BP) related to the large-scale forest clearing (Beysheir Occupation Phase). (2) Another pulse coincides with a major delta progradation of the Ceyhan River at about 2140 years BP. (3) A younger pulse follows the diversion of the Ceyhan River mouth toward Yumurtalik, from the Middle Age to 1935. Species interpreted as tolerant of low salinity indicate that the influence of the Ceyhan was minor whenthe river drained directly into the Mediterranean Sea (approximately 2000 years BP) and progressively increased when the river diverted towards Yumurtalik

New observations on asexual and sexual thalli of the Mediterranean species Lithophyllum racemus and description of its variability in a Tyrrhenian population have led to reinterpretation of the features of some fossil and living taxa. The external appearance and the reproductive and vegetative anatomy of the fossil species Lithophyllum viennotii corresponds to tetrasporangial plants of L. racemus. The fossil species Lithophyllum microsporum, whose holotype is redescribed here, represents a sexual stage of L. racemus, probably the carpogonial/carposporangial plants. Consequently, the stratigraphical distribution of L. racemus is widened back to the Aquitanian, and the species can thus be considered a Mediterranean paleoendemic. No character was found supporting the distinction of Lithophyllum duckeri from L. racemus, therefore this species is also considered conspecific with L. racemus.