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During the research for identification and monitoring of priority marine benthic habitats, an extraordinary rhodolith bed has been discovered at the Egadi Islands, Sicily, Southern Italy. Its exploration has been conducted, onboard the R/V Minerva Uno in July 2016, using a Multibeam Echosounder coupling with observations by ROV dive (video recording of > 1 km of seafloor) and direct sampling by Van Veen grab (70 l, 3 samples). Remote data and ROV inspections have been processed in order to produce a precise cartography of the habitat extension. ROV video and grab samples have been used to describe i) main sedimentary and biological features of the bed, ii) rhodolith morphotypes, iii) dominant algal species and iv) associated biodiversity. The rhodolith bed extends up to 7 km2 southeast of Marettimo Island and extended toward Favignana Island, at depth ranging between 90 and 100 m. Living rhodoliths cover up to 95% of the explored area. Patches of mobile biogenic sediments, mainly sand and gravel, are scattered within the living bed. Sedimentary structures, like megaripples and bioturbations by Spatangus sp. and Cydaris sp. are commonly visible on ROV video frames. Pralines are the dominant rhodolith morphotype, with medium size of L axis of 1.1 cm (max 3.4 cm), and an ellipsoidal to discoidal shape. The nucleus is formed by terrigenous clasts, or rarely, by biogenic components. Living calcareous algae are Phymatolithon lenormandii (Areschoug) Adey 1966, Lithothamnion spp. and L. valens Foslie 1909. The algal association at the nucleus of rhodoliths is characterized by different species, namely Lithophylloidea and Titanoderma spp.. The latter are representative of a shallower setting, perhaps the one occurring when the bed started to develop. Radiocarbon dating of the nucleus are still in progress, aimed at verifying this hypothesis and place the process of rhodolith formation in the correct temporal frame.

Coralline algae are among the most important marine calcifiers on a global scale, and are sensitive to rising temperatures and ocean acidification from the ongoing global climate change. Although diseases of coralline algae are known since the nineties in the Pacific Ocean, still few observations and studies are available on this topic. In the Mediterranean, similar events have been reported starting from 2015, in the north-western Mediterranean Sea, within 30 m of water depth. One of the commonest disease is the Coralline White Patch Disease (CWPD), that shows the bleaching of thallus patches due to cell necrosis. The CWPD is temperature-dependent, and it is suggested a relationship with the effects of global climate change. This contribution is aimed at describing CWPD in a rhodolith bed of the Egadi Islands (western Mediterranean). Two sites at a distance of 3 km have been sampled, at 86 and 103 m, by Van Veen grab, 60 l, three replicates each. Living rhodoliths have been selected and analysed for the occurrence of CWPD. A one-way ANOVA has been elaborated to test the difference in percent occurrence of diseased rhodoliths at the two sites. Rhodoliths affected by CWPD ranging in size between 1 and 4 cm are 5% and 5,7% of the total live rhodoliths, with no statistically significant difference between the two sites. At the depth of sampling, the influence of the rising temperature should be negligible, and other factors should be explored to explain the cause of the CWPD.

This contribution describes the white patch disease (CWPD) on coralline red algae (Rhodophyta, Corallinophycideae), observed for the first time in a rhodolith bed (aggregates of nodules of unattached growth forms of non-geniculate calcareous red algae) of the Aegadian Islands during the summer of 2016.

The Legnagnone section (North-eastern Apennines) represents one of the few shallow water records of the onset of the Messinian salinity crisis. Here we present a detailed description of a ~200 kyr time interval encompassing the pre-/syn-evaporitic transition based on a multidisciplinary approach, integrating sedimentological, bio-magnetostratigraphical, palaeontological and stable isotope data. Such a shallow water setting is potentially more sensitive to the palaeoenvironmental change leading to the MSC than the more often studied deeper Mediterranean basin. The aquatic palaeoenvironmental reconstruction proposed here is based on the study of foraminifer, ostracod and mollusc assemblages. It depicts a change from infralittoral (20–50 m) to inner circalittoral environment (60–100 m) that, since 6.12 Ma, was progressively affected by a reduction of oxygen at the sea floor punctuated by short-lived anoxic events. At least three cooling events have been recognized on the basis of relative abundance data in mid to high altitude pollen, which, before 6.03 Ma, are in phase with abundance peaks of Turborotalia spp., a taxon indicating eutrophic and cool surface waters. The absence of stress-tolerant benthic foraminifers during these peaks points to strong ventilation episodes triggered by a generally cooler climate. The proximity of a deltaic system and the consequent riverine input probably caused a salinity decrease of the surface waters, hindering the proliferation of planktonic foraminifers in the water column, which prevalently occur in short influxes and disappear at ca. 6 Ma. Our results suggest that the onset of the crisis occurred during a phase of relative sea level high stand, whereas no evidences of sea level drop can be envisaged. The palaeoclimatic reconstruction based on palynological data indicates the dominance of a “subtropical humid forest” vegetation type, where fresh water swamps are well represented. From 6.03 Ma onward, the transition to the salinity crisis is marked by more pronounced cyclical expansions of the temperate broad-leaved deciduous forest, along with herbaceous taxa. The establishment of the strongly evaporative condition at the crisis onset is not associated with major vegetational changes towards drier conditions, but linked to a sudden increase of δ18O and the disappearance of benthic foraminifers just prior to the deposition of the 1st laminated carbonate, which represents the base of the Primary Lower Gypsum unit.

Recent investigations of the Eastern Mediterranean Sea carried out during the GECO cruise with RV Urania provided a substantial number of new cold-water coral (CWC) records, including branching and solitary scleractinian species. These new sites are located along steep escarpments and on topographic highs along the margins of Crete, Karpathos, and Rhodes. The majority of the corals represent fossil occurrences, predominantly Late Pleistocene assemblages. Our research documents that the Eastern Mediterranean Basin has been colonized by CWC at favorable times during the Last Glacial, in particular during the Younger Dryas. Schizocyathus fissilis is reported for the first time for the Mediterranean, while the finding of Ceratotrochus magnaghii represents the first record for the Eastern Mediterranean. Various coral facies occur on the southerly island slopes of Crete, Karpathos, and Rhodes, including hardgrounds and loose skeletal sediments. Hardgrounds occur on steep topographies between ca. 500 and 1,700 m, and can conveniently be subdivided as (1) Neopycnodonte-Desmophyllum framestone, (2) Desmophyllum-Caryophyllia framestone, (3) Madrepora-Lophelia rudstone, (4) Pelagic mudstone and wackestone, and (5) Siliciclastic-carbonate conglomerate and breccia. Unconsolidated skeletal sediments containing corals mainly occur on gentler topographic situations between ca. 140 and 600 m and can be subdivided as: (A) Lophelia-Madrepora rubble, (B) Dendrophyllia rubble, (C) Stenocyathus rubble, (D) Caryophyllia calveri rubble, and (E) fine-grained sediment with octocoral axes. Many of these facies types are also present in the western part of the Mediterranean and have fossil representatives from the Pleistocene to the Recent. Radiocarbon dating (AMS- 14C) reveals Younger Dryas ages between 12.4 and 12.0 ka cal BP for Lophelia pertusa and Madrepora oculata. Desmophyllum dianthus occurs during the Last Glacial Maximum (21.8 ka cal BP) and the Younger Dryas (11.7 ka cal BP), as well as during the Late Holocene and subrecent times (4.4-0.6 ka cal BP). Caryophyllia sarsiae occurs during the Late Glacial (15.5 ka cal BP), while Caryophyllia calveri occurs during the Early Preboreal (10.8 ka cal BP). The ages for the framework-constructing corals L. pertusa and M. oculata are coherent with their temporal predominance during the Younger Dryas in other parts of the Mediterranean. © 2010 Springer-Verlag.

The Legnagnone section (North-eastern Apennines) represents one of the few shallow water records of the onset of the Messinian salinity crisis. Here we present a detailed description of a ~ 200 kyr time interval encompassing the pre-/syn-evaporitic transition based on a multidisciplinary approach, integrating sedimentological, bio-magnetostratigraphical, palaeontological and stable isotope data. Such a shallow water setting is potentially more sensitive to the palaeoenvironmental change leading to the MSC than the more often studied deeper Mediterranean basin. The aquatic palaeoenvironmental reconstruction proposed here is based on the study of foraminifer, ostracod and mollusc assemblages. It depicts a change from infralittoral (20-50 m) to inner circalittoral environment (60-100 m) that, since 6.12 Ma, was progressively affected by a reduction of oxygen at the sea floor punctuated by short-lived anoxic events. At least three cooling events have been recognized on the basis of relative abundance data in mid to high altitude pollen, which, before 6.03 Ma, are in phase with abundance peaks of Turborotalia spp., a taxon indicating eutrophic and cool surface waters. The absence of stress-tolerant benthic foraminifers during these peaks points to strong ventilation episodes triggered by a generally cooler climate. The proximity of a deltaic system and the consequent riverine input probably caused a salinity decrease of the surface waters, hindering the proliferation of planktonic foraminifers in the water column, which prevalently occur in short influxes and disappear at ca. 6 Ma. Our results suggest that the onset of the crisis occurred during a phase of relative sea level high stand, whereas no evidences of sea level drop can be envisaged. The palaeoclimatic reconstruction based on palynological data indicates the dominance of a "subtropical humid forest" vegetation type, where fresh water swamps are well represented. From 6.03 Ma onward, the transition to the salinity crisis is marked by more pronounced cyclical expansions of the temperate broad-leaved deciduous forest, along with herbaceous taxa. The establishment of the strongly evaporative condition at the crisis onset is not associated with major vegetational changes towards drier conditions, but linked to a sudden increase of ?18O and the disappearance of benthic foraminifers just prior to the deposition of the 1st laminated carbonate, which represents the base of the Primary Lower Gypsum unit.

The Hermes oceanographic mission ARCO (AdRiatic COrals: 13-22 December 2008, R/V Urania) was organized by CNR-ISMAR with the goal to identify and map yellow coral (Dendrophyllia cornigera) thickets up to 1 m high at intermediate depths (ca 200 m) in the region of the Middle Adriatic Depression (MAD). Previous AMS-C14 dating of Dendrophyllia corals from this area provided a late Holocene age ; furthermore, some specimens are heavily bioeroded and encrusted by living or recently dead epifauna including polychaetes and Neopycnodonte oysters. This evidence suggests that this yellow coral is still alive in the middle Adriatic at this location. The presence of coral grounds here is well known to fishermen that avoid the area for the potential damage to their nets. During ARCO, the area known to host corals was first mapped in detail and imaged by multiswath bathymetry, chirp and side scan sonars, revealing bottom features that were interpreted as potential coral mounds. A ROV survey however did not image as expected Dendrophyllia coral thickets emerging from the muddy area draping the topographic highs between the major depressions. Instead, bottom sampling (large volume grab, gravity corer etc.) recovered a large amount of dead ‘white corals’. Before our finding, there were only a few sporadic citations of such corals at these Adriatic latitudes, summarized by Zupanovic and Jardas (1989). The ‘white corals’ are mainly the branching scleractinians Lophelia pertusa and Madrepora oculata, with subordinate Dendrophyllia cornigera, and Caryophyllia smithii ; the solitary coral Desmophyllum dianthus is rare. Encalcified Eunice parchment tubes were consistently associated with Lophelia and Madrepora frames. Although extremely well preserved and with alabastrine luster, the white corals were all dead and covered by a thin layer of mud (< 15 cm, Minicore ARCO- and gravity core ARCO-). Corals do not show Fe-Mn oxide patinas, and bioerosion or fouling is limited. Dead individuals of the cemented bivalves Neopycnodonte cochlear and, more rarely Spondylus gussonii, are occasionally found attached to Lophelia colonies. Interestingly, most ‘white corals’ are represented by individuals of unusually large size and thickness. Differently from (part at least of) Dendrophyllia colonies, the Lophelia-Madrepora thickets are possibly extinct in the MAD. They might have belonged to a coral province that established at the end of the last glacial age on topographic highs of the MAD on both sides of the Italo-Croatian midline. At present live Lophelia thriving at shallow depths is found in Norwegian fjords. It is quite remarkable that Lophelia has been found at such shallow depth in the Adriatic. Furthermore, the actual depth of recovery (ca. 200 m) should be considered as the maximum figure since at the presumed time of their life at the end of the Pleistocene, sea level was lower than present and corals possibly settled the area when it was only some 100-120 m deep. A number of Pleistocene shells were also recovered from this site, including infaunal boreal species such as the bivalves Panopea norvegica, Pseudamussium peslutrae and the vagrant gastropod Buccinum humphreysianum together with unusually large axes of the octocoral Funiculina quadrangularis. Essentially, this region of the MAD seems a frozen-in-time latest glacial seascape. On-going U/Th and AMS-C14 dating will reveal the age of these subfossil ‘white corals’. As a working hypothesis, we suggest tentatively that they were lethally impinged by a sudden silting, perhaps in response of a milder climatic pulse resulting in stronger rains and enhanced sediment transport in the Adriatic. A similar situation has been documented elsewhere in the Mediterranean basin but at deeper bathymetries (e.g., Remia and Taviani, 2005). The discovery of this large (supposedly) glacial deep water coral province in the middle Adriatic is highly significant in understanding the general spatio-temporal evolution of deep water corals in the Mediterranean basin and may help in assessing the links among the recently discovered coral provinces of the southern Adriatic and Ionian seas.