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The prosobranch molluscs of Britain and Denmark. Part 3. Neritacea, Viviparacea, Valvatacea, terrestrial and freshwater Littorinacea and Rissoacea

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... 18); older ones were usually darker than juveniles. Pale snouts are still usually darker laterally than dorsally (Fretter & Graham, 1978) The foot is translucent white with some opaque white spots and, dorsally, pale grey and/or palebrown shading ( fig. 15). ...
... Populations are drastically reduced in winter in northern Europe when Zostera leaves die and drop; only a small portion survives to reach maturity and breed in the following summer ( van Goor, 1919, in Cadée 1998. Shell sculpture apparently responds to small changes in environment in a similar way to that described by Wigham (1975a) for Rissoa parva (Fretter & Graham, 1978) with ribbed forms tending to occur more frequently sublittorally ( The respiratory inhalent current comes into the mantle cavity at the left of the head and has the water quality tested by the osphradium before reaching the grey-white ctenidium with substantial filaments (fig. 19). ...
... Post-embryonic larvae are present in Northern Europe during the summer; in Denmark, from May to September when the water is above 10ºC, (Rasmussen, 1973). Breeding is all year on the south coast of England, France and places further south (Fretter & Graham, 1978), and there are reports of egg capsules in most months even from northern localities (Warén, 1996). Differences in development have been distinguished between two types, named variously by different authors: 1) Type : A (Rehfeldt, 1968); planktotrophic (Cadée, 1998); Rissoa labiosa (Verduin, 1982); Distribution: Norway to the Mediterranean and Black Sea (Verduin, 1982). ...
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Illustrated species account of Rissoa membranacea (J. Adams, 1800) Identification and Biology, (Mollusca, Littorinimorpha). Includes similar forms and species.
... In the British Isles the species lives among weeds on rocky shores with Zostera and Codium (Fretter & Graham, 1978). Warén (1996a) found the species almost always together with Rissoa membranacea (Adams) on algae and Zostera, but never on open coasts in exposed environments. ...
... Recent distribution, ecology, and biology: Alvania punctura is a boreal-lusitanian species (Fig. 7.8). It extends in the North Atlantic region from the Kola Peninsula, western Norway (at about 70°N), and the Faroe Islands in the north to the Mediterranean in the south (Fretter & Graham, 1978;Nekhaev, 2014;Warén, 1996b). It is present at the Swedish west coast and the western part of Øresund, but not in the Baltic, the east shores of the North Sea nor the eastern basin of the English Channel (Fretter & Graham, 1978;Jensen & Knudsen, 1995). ...
... It extends in the North Atlantic region from the Kola Peninsula, western Norway (at about 70°N), and the Faroe Islands in the north to the Mediterranean in the south (Fretter & Graham, 1978;Nekhaev, 2014;Warén, 1996b). It is present at the Swedish west coast and the western part of Øresund, but not in the Baltic, the east shores of the North Sea nor the eastern basin of the English Channel (Fretter & Graham, 1978;Jensen & Knudsen, 1995). It is not known from Iceland. ...
Chapter
Systematic overview of the molluscan and barnacle assemblages of the Pliocene Tjörnes sequence in North Iceland is primarily based on collections and fieldwork carried out during the last 50 years and collections of the Institute of Natural History in Reykjavík, the Geological Museum in Copenhagen, and the collection of the late farmer Jóhannes Björnsson in Ytri-Tunga on Tjörnes. We have identified 65 species of prosobranch gastropods, five opistobranch gastropod, 49 bivalve, one ammonite, and one barnacle species. Of the 119 molluscan species, 24 have not been recorded before from Tjörnes. About 25% of the mollusc species are extinct, and 25 of the recent molluscan species now live in southerly localities with higher sea temperatures. At least 32 of the species have their first appearance (FAD) in Tjörnes. The species are depicted on plates and variation in shape is demonstrated wherever possible. The distribution, recent or fossil, of species is shown, and ecological and biological features discussed. The larval development of the species is also summarized. The Tjörnes fauna is major record of trans-Arctic oceanic interchange that has been imperative in shaping the modern North Atlantic faunas. This review enables us to improve our understanding of the interchange.
... A characteristic feature of the capsules is the presence of keel and basal ring (Fig. 19 G). The life span is estimated at one year (Fretter & Graham 1978). ...
... The food includes diatoms, rotting plant tissues and detritus (Fretter & Graham 1978 (Piechocki 1979, Falniowski 1987a, Serafiński et al. 1995. M. insubrica is among the least known aquatic snails of Poland, which may be associated with its small size and low abundance. ...
... 2.5 mm, they start reproducing. The estimated life span is 1.5-2 years (Fretter & Graham 1978). ...
Book
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The volume includes 280 pages of text and 156 figures, both drawings and photographs. Book covers all the species of Mollusca found so far in Polish waters, i.e. 63 species of Gastropoda (54 freshwater, 9 marine) and 47 species of Bivalvia (37 freshwater, 10 marine). The general chapters contains detailed descriptions of the molluscan morphoanatomy as well as ecology of snails and bivalves. In the systematic chapters, the readers will find keys to families, genera and species as well as detailed descriptions of each species, including shell, variability and similarity to other species, soft parts, ecology and biology, distribution. Shells of all species are presented on colour photos.
... P. elegans is a European species (Kerney and Cameron, 1999), widespread in calcareous soils, wherever the calcium carbonate content exceeds $20% (e.g. Fretter and Graham, 1978). It is typically found in warmer, moist, shady biotopes and occurs mainly in damp sites , from 10-12 8C to the optimal temperature range of 25-30 8C and humidity of 95% (Fretter and Graham, 1978). ...
... Fretter and Graham, 1978). It is typically found in warmer, moist, shady biotopes and occurs mainly in damp sites , from 10-12 8C to the optimal temperature range of 25-30 8C and humidity of 95% (Fretter and Graham, 1978). In the Italian peninsula P. elegans is also present in coastal dune vegetation, as well as in mixed woodlands with xerothermophilous elements such as those found in some piedmont hilly areas (Giusti and Castagnolo, 1982). ...
... In the Italian peninsula P. elegans is also present in coastal dune vegetation, as well as in mixed woodlands with xerothermophilous elements such as those found in some piedmont hilly areas (Giusti and Castagnolo, 1982). It is a herbivorous species feeding mainly on dead leaves, amongst which it lives (Adam, 1960;Fretter and Graham, 1978). The snail probably lives for 4-5 years but more information is required on its life expectancy (Fretter and Graham, 1978). ...
... Bithynia tentaculata is a wide-spread freshwater prosobranch gastropod with a life period of one to three years, although growth may stop after the first year (Fretter and Graham 1978;Graham 1988). Bithynia also grows during winter; therefore a complete shell (or operculum) records the variations in temperature, chemistry and isotopic signatures of water during the life time. ...
... As reported above, Bithynia tentaculata grows along the first year of life (cf. Fretter and Graham 1978), therefore the isotopic signature of a complete shell (or operculum) may be proxy of the mean isotopic and T values of the water where it grew during a year. Filippi et al. (1997) concluded that d 18 O signatures from aragonite molluscs and other modern carbonates from Lake Geneva are near oxygen isotope equilibrium. ...
... Tarutani et al. 1969;Romanek et al., 1992). Fretter and Graham (1978) provide data from diverse authors that indicate that B. tentaculata animals fed and grew throughout the year, the maximum growth being in summer, and only in the most extreme winters growth stops. ...
... These are exclusively iteroparous species. Some iteroparous species, however, show other life cycle patterns, for example type A has been found in Valvata piscinalis (FRETTER & GRAHAM 1978, GRIGOROVICH et al. 2005. ...
... Viviparid embryos develop within the egg capsules (FRETTER & GRAHAM 1978). In the mother's brood chamber the embryos are arranged according to the advancement of their development. ...
... Viviparidae acquire most of their food with the radula, but they can facultatively become filter feeders (FRETTER & GRAHAM 1978). The viviparid diet consists mainly of algae scraped with the radula, higher aquatic plants and detritus (FRÖMMING 1956, STAÑCZYKOWSKA et al. 1972, PIECHOCKI 1979, JAKUBIK 2009a. ...
... The abundance of peloids in the matrix and their regular shape and comparable size (50-100 mm) may be interpreted as faecal pellets and likely results from the presence of abundant molluscan and crustacean cummunities. The molluscan assemblage dominated by Polymesoda and Hydrobia and Tarebia is indicative of warm, shallow and oligo-mesohaline waters (Daley, 1972;Morton, 1983, Fretter and Graham, 1978, Lettéron et al., 2017. Extant Polymesoda bivalves are found in a variety of variable salinity shallow environments (Reichenbacher et al., 2004;Harris et al., 2015) and their optimal depth is lower than 1 m (Tabb and Moore, 1971) even though these may be found at depths of 10 m (Morton, 1983;Lettéron et al., 2017). ...
... Polymesoda are found both valves connected thus indicating deposition in their living environment. Extant Hydrobia acuta neglecta are found in coastal lagoons where salinity ranges between 10 and 24‰ (Fretter and Graham, 1978). Thus, the biological community of F2A facies, particularly through the presence of Hydrobia, exhibits the greatest tolerance to salinity elevation compared to the freshwater to oligo-mesohaline gastropods and charophytes found in the overlying and underlying levels (F2B and F2D facies, see descriptive sections hereinafter). ...
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The integrative analysis of a lacustrine carbonate succession from Butte Iouton hill (Vistrenque basin, SE France) brings new insights into depositional models of oolitic saline lake margins and provides new details regarding the late Eocene paleogeography of southeast France. Depositional facies analysis and paleoenvironmental reconstructions allow reconstructing an oolitic lacustrine ramp model, displaying from the proximal to the distal areas: 1) shallow marginal saline lake domain with deposition of planar microbial laminites, and molluscan-ostracodal wackestone, 2) a more distal and open lacustrine environments with low to moderate energy characterized by the deposition of peloidal grainstones and 3) a domain of higher energy with accumulation of ooids mixed with peloids in the vicinity of the area of ooid production. Lake margin carbonate sedimentation dominantly occurred during stages of lake transgression while subaerial exposure surfaces developed during periods of negative inflow-evaporation balance. Carbon and oxygen isotopes together with vertical trends in salinity inferred from molluscan associations show that lake transgression does not result from increasingly positive freshwater-evaporation balance volume but from the combination of subsidence and outflow from neighbouring salt waterbodies. The Butte Iouton carbonate margin is part of a set of interconnected saline lakes, occupying continental basins from Languedoc and Rhodanian region during the Priabonian, with a siliciclastic-dominated sedimentation in the southern margin, sourced by collapsing Pyrenean reliefs, and a carbonate-dominated northern margin with significant oolitic sedimentation in high-energy nearshore area.
... En laboratoire, le temps de génération minimum est de 6 mois (Winterbourn 1970), ce qui permet d'avoir deux générations par an (Frenzel 1979 (Rittschof et al., 2002). Les oeufs sont pondus dans des masses gélatineuses attachées à la végétation ou, plus rarement à des pierres (Fretter et Graham 1978). ...
... Or, les deux organismes modèles se distinguent par des modes alimentaires différents. P. antipodarum est un détritivore , ou un fouisseur suivant les auteurs (Michaut 1968), alors que V. piscinalis est un racleur (Cleland 1954), ou détritivore (Fretter et Graham 1978). De plus, leur cycle de vie diffère quelque peu, ce qui implique que leur exposition à des contaminants n'est certainement pas quantitativement et qualitativement comparable. ...
Thesis
L'effet des perturbateurs endocriniens sur les écosystèmes aquatiques est un sujet d'intérêt majeur en écotoxicologie, mais reste mal évalué sur les invertébrés et notamment les mollusques gastéropodes. Pourtant, ces derniers sont sensibles aux perturbateurs endocriniens, mais les mécanismes rentrant en jeu sont méconnus, du fait du faible niveau de connaissance de leur système endocrinien. Deux espèces d'étude ont été choisies, pour leur grande similitude de traits de vie, mais avec un mode de reproduction différent. Dans ce travail, nous avons développé des outils à différents niveaux d'organisation biologique afin de mieux appréhender les modalités de l'action reprotoxique des polluants. Les différents marqueurs (suivi de reproduction, histopathologie, réserves énergétiques, stéroïdes sexuels, protéines vitelline-like) ont été développés ou adaptés chez nos espèces. Leur variabilité naturelle ou due à des facteurs autres que des polluants (température d'exposition) a été évaluée en partie. Un développement particulier a été réalisé pour les stéroïdes sexuels de type vertébrés, afin de mieux comprendre leur implication dans le contrôle de la reproduction de P. antipodarum, et leur possible utilisation en tant que marqueurs de la perturbation endocrinienne. Ces marqueurs ont ensuite été appliqués au laboratoire et sur le terrain. Une méthodologie d'exposition in situ a été développée et des expositions à des pollutions diverses (rejet de stations d'épurations, contamination multi-métallique) ont été réalisées pour mieux caractériser la pertinence respective des marqueurs utilisés. Nous avons comparé la sensibilité interspécifique des deux espèces de travail, et tirons quelques recommandation sur l'utilisation de P. antipodarum comme modèle OCDE pour l'évaluation des effets reprotoxiques.
... E. ventrosa (= Hydrobia ventrosa) is frequently found in mesohaline waters, such as brackish lagoons (Giusti & Pezzoli, 1984). These two Hydrobiidae species frequently live together (Barnes, 2005) in water basins characterised by a salinity ranging from 2‰ to 34‰, even if they prefer the narrower range 6‰ -25‰ (Fretter & Graham, 1978). ...
... T. subcylindrica lives (often buried) on soft muddy bottoms, in either subaqueous or occasionally submerged environments whose salinity ranges from 18‰ to 40‰. It can also be found under hips of decomposing vegetal remains (Fretter & Graham, 1978). ...
... E. ventrosa (= Hydrobia ventrosa) is frequently found in mesohaline waters, such as brackish lagoons (Giusti & Pezzoli, 1984). These two Hydrobiidae species frequently live together (Barnes, 2005) in water basins characterised by a salinity ranging from 2‰ to 34‰, even if they prefer the narrower range 6‰ -25‰ (Fretter & Graham, 1978). ...
... T. subcylindrica lives (often buried) on soft muddy bottoms, in either subaqueous or occasionally submerged environments whose salinity ranges from 18‰ to 40‰. It can also be found under hips of decomposing vegetal remains (Fretter & Graham, 1978). ...
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Mastronuzzi M., Milella M., Piscitelli a., siMone o., Quarta G., scarano t., calcaGnile l. & sPada i., Landscape analysis in Torre Guaceto area (Brindisi) aimed at the reconstruction of the late Holocene sea level curve. (IT ISSN 0391-9838, 2018). This paper focuses on four different cores drilled in the Area Marina Protetta e Riserva dello Stato di Torre Guaceto (Carovigno, Brindisi). The stratigraphic, sedimentological and paleontological characteristics were related to the geomorphologic features of the whole area and to the radiometric dating of the peaty levels identified in the stratigraphic sequence; the results have been compared with the available geo-archaeological data. The complete data-set allowed to reconstruct the succession of sedimentary environments over time and to place these across the last 2200 years, thanks to radiometric dating. In the stratigraphic sequence, it was possible to highlight layers that indicate coastal areas marked by the presence of inlets in connection with the sea, areas submerged during tides and brackish or continental areas. In particular, the research demonstrated , with good approximation, that the sea level had to be stationed at about-1.1 ± 0.1 m approximately 2200 years BP; then it went to about-0.65 ± 0.1 m about 1900 years BP and continued its rise to the current position. Finally, the comparison of the stratigraphic data with the geophysical predicted sea level curve for the late Holocene indicates that vertical movements in this span of time did not affect this area. This confirms what has recently been established for this area as regards the stability of the Adriatic side of the Apulian foreland. riAssunto: Mastronuzzi M., Milella M., Piscitelli a., siMone o., Quarta G., scarano t., calcaGnile l. & sPada i., Analisi del pae-saggio di Torre Guaceto (Brindisi) per la ricostruzione delle variazioni tardo oloceniche del livello del mare. (IT ISSN 0391-9838, 2018). Nell'Area Marina protetta e Riserva dello Stato di Torre Guaceto, presso Carovigno in Provincia di Brindisi, sono stati realizzati quattro differenti carotaggi. Le caratteristiche stratigrafiche, sedimentologi-che e della malacofauna contenuta sono state messe in relazione con quelle geomorfologiche dell'area di studio e con datazioni radiometri-che di livelli di torba provenienti dai carotaggi, oltre che correlate con dati geoarcheologici derivanti da studi precedenti. L'insieme dei dati disponibili ha permesso di ricostruire la successione degli ambienti sedimentari nel tempo e di collocare questi, grazie alle datazioni ra-diometriche, negli ultimi 2200 anni circa. Aree costiere segnate dalla presenza di insenature in connessione con il mare, aree inondate du-rante le maree e aree salmastre o schiettamente continentali sono rico-noscibili nei carotaggi. In particolare, è possibile affermare con buo-na approssimazione che il livello del mare dovette stazionare a circa-1.1 ± 0.1 m circa 2200 anni dal presente per poi passare a circa-0.65 ± 0.1 m circa 1900 anni e quindi continuare la sua risalita sino alla posizione attuale. Infine, il confronto con le più recenti curve di variazioni del livello del mare relative al tardo Olocene indicano che quest'area non è stata interessata da movimenti verticali in questo in-tervallo di tempo, confermando quanto recentemente appurato per questa zona dell'avampaese Apulo. termini chiAve: variazioni del livello del mare, paesaggio costiero; ambiente costiero, Torre Guaceto, Puglia, Italia. Geogr. Fis. Dinam. Quat.
... Also in Western and Northern Europe P. antipodarum is now widespread and very common (JAECKEL 1962, FRETTER & GRAHAM 1978, WILLMANN & PIEPER 1978, GLÖER & MEIER-BROOK 1994, GITTENBERGER et al. 1998, KERNEY 1999. According to a common opinion, the expansion of the species in European waters is associated with the fact that it can survive at salinity from 0 to 17‰, its parthenogenetic reproduction and ability to live in a variety of stagnant and flowing waters. ...
... According to a common opinion, the expansion of the species in European waters is associated with the fact that it can survive at salinity from 0 to 17‰, its parthenogenetic reproduction and ability to live in a variety of stagnant and flowing waters. As pointed out by FRETTER & GRAHAM (1978), an important role in invasion of new water bodies is played by a passive dispersal: the snail is transported with ballast water of ships, attached to floating objects or clumps of drifting vegetation, or sent over long distances with fish fry or aquatic plants. Birds and fishes may considerably contribute to its dispersal. ...
... Starting with primary coiled forms (Neritimorpha), it appears to be a general rule that the blood from the haemocoel of the animal's body is at first filtered by the (right or single left) kidney, and then is oxygenated by passing the respiratory organs. This is in clear contrast to the conditions of the allogastropod and euthyneuran groups, where a (pallially situated, see below) kidney is supplied by blood coming from the mantle cavity and acts as an (additional or solely) respiratory organ (Brace, 1977a(Brace, , b, 1983Fretter, 1978;Haszprunar, 1985c, d, f). The latter is obviously a commonly derived (syn-apomorphic) situation of Allogastropoda and Euthyneura. ...
... These, however, differ entirely in their structure from the original cartilages and obviously are secondary structures. Although all valvatids investigated are herbivorous (Fretter & Graham, 1978), their lack of cartilages together with other modifications of their alimentary canal suggest an original carnivorous habit ; see also below and 54.6.1.). ...
Article
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The phytogeny and evolutionary history of the strep-toneuran Gastropoda is reconsidered in the light of (i) recent discoveries of different types of organization, (ii) new data sets based on modern techniques, and (iii) the dado-evolutionary method to trace genealogical relationships. The phylogcnctic analysis by means of traditional (homology-analogy) and cladistic (apomorphy-plesiomorphy) character analysis reveals several conclusions: (1) The Gastropoda originated by torsion from monoplacophoran ancestors after the Cephalopoda split off. Torsion itself is understood as a two-step process, resulting in advantages for the larvae (presence of operculum) and for the adults (anterior mantle cavity). All Gastropoda form a holophyletic group (2) The proposed gastropod archetype differs Largely from previous suggestions in being more similar to docoglossate gastropocls than to zeugobranchs (3) The Docoglossa are regarded as the earliest gastropod offshoot, having retained ancestral (atereoglossate) radula conditions (4) Based on various lines of evidence the ‘symmetrical’ limpet groups (Docoglossa, including hotvent group-C?, Cocculiniformia), primary without helicoid coiling of teteoconch, are accepted as primithe for the Gastropoda (5) CocculinifOrmia, Neritimorpha and possibly hot-vent group-A represent distinct archaeogastropod radiations (6) The Vetigastropoda, originally including zeugobranchs and trochoids are a hotophyletic group and include also the Lepetodriloidea (= hot-vent group-B). In contrast, the Neomphaloidea and Seguen zioidea represent distinct Lines of evolution (7) According to their hypoathroid or dystenoid nervous system the architaenioglossate groups are included in the *Archaeogastropoda* which are defined as an orthophyletic grade (8) A major evolutionary gap (a large inaease in size enabled ptanktotrophic larvae; epiathroid nervous system) separates the higher streptoneurans (= *Apogastropoda*) from the *Archaeogastropoda*. The Loxonematoidea are regarded as the common stem group of Caenogastropoda as well as of the ectobranch—allogastropod—euthyneuran line (Heterobranchia) (9) The Caenogastropoda are a holophyletic group, of which the Centhioidea represent the basic stock. The Stenoglossa (= Neogastropoda) probably origined from *Neotaenioglossa* sharing distinct simitanSies in sperm-morphology (10) Canpani1e symbolicum Iredale, 1917 (Campanhimorpha) is a probable representative of the first group that made a distinct step towards the euthyneuran organization (11). Valvatoidea (Ectobranchia) form a separate offshoot outside the Caenogastropoda. They appear as an independent side-branch at the base of the allogastropod grade (12) The *Allogastropoda*, a grade, include the fossil Nerineoidea and at least four recent lines (Architectonicoidea & Omalogyridae; Rissoelloidea; Glacidorboidea; Pyramidelloidea) which represent a step by step evolution towards the euthyneuran level of organization (13) Euthyneura are monophyletic. However, the status of the Opisthobranchia (bob- or paraphyletic) is still ambiguous. The Pulmonata (including the Gymnomorpha) represent a holophyletic assemblage and the own group of Gastropoda (14) The respective phylogram (Fig. 5) is transformed in a classification by the use of the so-called clado-evotutionary method which enables an unequivocal retransformation and expresses the different degrees of likelihood (correlated with the main evolutionary gaps) in the proposed phylogenetic pathway of the streptoneurous Gastropoda
... All bivalve and gastropod specimens >2 mm in any dimension were identified to the lowest possible taxonomic level, typically species (Fretter and Graham, 1976;Fretter and Graham, 1977;Fretter and Graham, 1978a;Fretter and Graham, 1978b;Fretter and Graham, 1980;Fretter and Graham, 1981;Fretter and Graham, 1982;Fretter and Graham, 1984;Huber, 2010;Cossignani and Ardovini, 2011;Huber, 2015) and counted per sample. Using the minimum number of individuals (MNI) approach (Gilinsky and Bennington, 1994), a quantifiable specimen was defined as a single bivalve valve with a complete beak or gastropod with an intact apex. ...
Article
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Framework-forming scleractinian cold-water corals (CWCs) act as ecosystem engineers, building and supporting biodiversity hotspots in the deep sea worldwide. While spatial patterns and drivers of species distributions have been evaluated on modern CWC reefs, little is known about how reef diversity is affected by habitat variability over geologic time – the scale at which CWC reefs initiate, thrive, and decline. Using three CWC reef sediment cores as species diversity archives, we investigated temporal trends of molluscan diversity over the last ~13 kyr from a CWC mound in the Alboran Sea (western Mediterranean Sea) to evaluate (a) how spatial patterns of CWC-associated diversity are recorded in reef sediments, (b) the potential of CWC reefs as biodiversity hotspots when coral growth is flourishing and when it is not, and (c) which palaeoceanographic conditions or habitat characteristics may be driving biodiversity. Our results reveal that at the ecosystem scale ecological differences between CWC habitats are more pronounced than ecological signatures of molluscan assemblages associated with intervals of CWC framework (flourishing growth) or non-framework (negligible CWC growth). However, within habitats, significant differences emerge between these assemblages with lower molluscan diversity associated with flourishing CWC growth. Significant negative correlations between molluscan diversity and palaeoceanographic conditions conducive for CWC growth (high food availability, strong hydrodynamics, optimal bottom-water temperatures and salinities, and high aggradation rates indicative of flourishing CWC growth also imply that CWC growth and relevant environmental conditions contribute to reduced molluscan diversity. Additionally, high coral volume, used here as a proxy for habitat structural complexity, is positively correlated with molluscan diversity just as high habitat complexity is in living CWC reefs. Altogether, these patterns detected over geologic time resemble those observed spatially across living CWC reefs today – where competition with resources, particularly food, prevents high reef biodiversity in the immediate vicinity of dense living CWC colonies. Overall, our study demonstrates that (1) ecological paradigms of living CWCs are preserved in their sedimentary record, (2) flourishing CWC growth and conditions promoting CWC growth drive habitat-scale diversity patterns, and (3) a geological approach can be applied to study long-term diversity dynamics in CWC ecosystems.
... All bivalve and gastropod specimens >2 mm in any dimension were identified to the lowest possible taxonomic level, typically species (Fretter and Graham, 1976;Fretter and Graham, 1977;Fretter and Graham, 1978a;Fretter and Graham, 1978b;Fretter and Graham, 1980;Fretter and Graham, 1981;Fretter and Graham, 1982;Fretter and Graham, 1984;Huber, 2010;Cossignani and Ardovini, 2011;Huber, 2015) and counted per sample. Using the minimum number of individuals (MNI) approach (Gilinsky and Bennington, 1994), a quantifiable specimen was defined as a single bivalve valve with a complete beak or gastropod with an intact apex. ...
Conference Paper
Framework-forming cold-water corals (CWC) are ecosystem engineers, building and supporting deep-sea biodiversity hotspots worldwide. While spatial patterns and drivers of species distributions have been evaluated on modern CWC reefs, little is known how reef biodiversity is affected by habitat variability over geologic time – the scale at which CWC reefs initiate, thrive, and decline. Using three CWC reef sediment cores as species diversity archives, we investigated temporal trends of molluscan diversity over the last ~13 kyr from a CWC mound in the Alboran Sea to evaluate (a) how spatial patterns of CWC-associated diversity are recorded in reef sediments, (b) the potential of CWC reefs as biodiversity hotspots when coral growth is flourishing and when it is not, and (c) which palaeoceanographic conditions or habitat characteristics may be driving biodiversity. Our results reveal that at the ecosystem scale differences in molluscan assemblages are more pronounced between CWC habitats than between intervals of CWC framework (flourishing growth) and non-framework (negligible CWC growth). However, within habitats, significant differences emerge between these assemblages: lower molluscan diversity is associated with flourishing CWC growth. Significant negative correlations between molluscan diversity and palaeoceanographic conditions conducive for CWC growth (high food availability, strong hydrodynamics, optimal bottom-water temperatures and salinities, high aggradation rates indicative of flourishing CWC growth) also imply that CWC growth and relevant environmental conditions contribute to reduced molluscan diversity. Altogether, these patterns detected over geologic time resemble those observed spatially across living CWC reefs today – where competition with resources, particularly food, prevents high reef biodiversity near dense living CWC colonies. Our study demonstrates that (1) ecological paradigms of living CWC are preserved in their sedimentary record, (2) flourishing CWC growth and conditions promoting CWC growth drive habitat-scale diversity patterns, and (3) a geological approach can be applied to study long-term diversity dynamics in CWC ecosystems. Session No. 139 D23. Paleontology: Recent Developments in Diversity, Extinction, and Origination Tuesday, 11 October 2022
... Es más abundante en los tramos tranquilos de ríos, especialmente cuando existe materia orgánica en suspensión, aunque también puede localizarse en zonas donde la corriente es más intensa. Habita sobre la vegetación, bajo las piedras cuando ésta es escasa o está ausente y sobre substrato blando, en el que se entierra en invierno (Fretter & Graham, 1978;Gloër, 2002). Es una especie para la que se ha registrado un máximo de resistencia a la desecación de 12-14 días (Pelseneer, 1935) así como una tolerancia a la salinidad que le permite vivir en aguas de hasta el 12‰ (Adam, 1960). ...
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The results obtained in the analysis of the malacological assemblage of two samples belonging to layer D of the Lower Pleistocene deposit of Barranco León (Guadix-Baza Basin) are presented. The main results obtained are the list of species of the malacological assemblage and their relative abundance, which indicate their marked aquatic character. On the other hand, despite the limitations imposed by the scarcity of taphonomic information and the caution suggested by certain indicators, a paleoenvironmental interpretation of the conditions existing at the time of the deposit is provided, based on the analysis of the ecological requirements of each taxon. These would correspond to the marginal zone of a permanent lake, oligohaline, of lentic regime, with little depth, presence of macrophytes and existence of thermal upwellings. This lake would be surrounded by littoral vegetation in what would constitute a strip of hygrophilic fl ora framed in an open space in which the climatic conditions would be more xeric in character and in we would fi nd a Mediterranean scrub otted with tree clusters.
... Es sei hier nur auf Tr uncatella subcylindrica verwiesen (A bb. [26][27][28]: in gängiger taxonomi­ scher Auffassung sind gerippte Formen mit Außenwulst und glatte Formen ohne Außenwulst konspezifisch (FRETTER & GRAHAM 1978). Bei Nystia pupiniformis ist die Protokonchgröße gleich der von N. pseudoplicata, und der Apex noch schlan­ ker; die Axialrippen sind mehr oder minder rudimentär. ...
... The habitat (intertidal) and the shell characters of the studied specimens' conform to the descriptions available in the literature (e.g. Fretter & Patil, 1958;Fretter & Graham, 1978;Rubio & Rodríguez Babío, 1995 The total number of shallow-water marine molluscs reported for the Azores between 2000 and 2017 has risen from 231 (Ávila, 2000) to 385 species (280 gastropods, 90 bivalves, 8 cephalopods and 7 chitons). More importantly, 41 (10.6%) are endemic species, in contrast with the 19 (8.2%) recorded in 2000. ...
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A benthic survey in the Azores Archipelago revealed the presence of the microgastropod Eatonina fulgida, herein reported for the first time. This finding expands the known geographical distribution of this species in the northeast Atlantic Ocean. The Azorean specimens are described and additional observations on the shell features of the species are provided. With this new record, the number of shallow-water (< 50 m depth) marine molluscs reported for the Azores increases to a total of 385 species, 280 of which are gastropods.
... The mollusk record is characterized by some brackish-water taxa (among which Hydrobiidae, A. segmentum and C. glaucum, in order of abundance) typical of the euryhaline and eurythermal lagoons (LEE sensu Peres and Picard, 1964). Hydrobiidae are herbivores or surface detritivores burrowers adapted to euryhaline conditions ranging from 2 to 34‰ even if usually they prefer the range 6e25‰ (Fretter and Graham, 1978), C. glaucum is a filter-feeder normally living in water bodies characterized by salinities between 18 and 37‰ (Vatova, 1981), and A. segmentum is a browser-burrower which thrives in a salinity range of 14e27‰. Therefore the contemporaneous occurrence of these three taxa might suggest a range of salinity between 18 and 27‰. ...
Article
A 25 m-thick outcrop section exposed at Torre Mucchia, on the sea-cliff north of Ortona, eastern central Italy, comprises a rare Middle Pleistocene succession of shallow-water and paralic sediments along the western Adriatic Sea. An integrated study of the section, including facies and microfacies analyses, and characterization of paleobiological associations (mollusks, fishes, ostracods, foraminifers and pollen), enable a detailed reconstruction of the paleoenvironmental and paleoclimatic conditions during deposition. The shallow-water deposits include a transgressive, deepening- and fining-upward shoreface to offshore-transition facies succession overlain by a regressive shoreface-foreshore sandstone body with an erosive base and a rooted and pedogenically altered horizon at the top that imply deposition during sea-level fall. This forced regressive unit is overlain by paralic strata forming a transgressive succession comprising palustrine carbonates and back-barrier lagoonal mudstones. The palustrine carbonates exhibit some of the typical features encountered in palustrine limestones deposited within seasonal freshwater wetlands (marl prairies). Following the sea-level rising trend, the freshwater marshes were abruptly replaced by a barrier-lagoon system that allowed deposition of the overlying mud-rich unit. Within these deposits, the faunal assemblages are consistent with a low-energy brackish environment characterized by a relatively high degree of confinement. The pollen record documents the development of open forest vegetation dominated by Pinus and accompanied by a number of mesophilous and thermophilous tree taxa, whose composition supports a tentative correlation with Marine Oxygen Isotope Stage 17. The new pollen record from Torre Mucchia improves our understanding of the vegetation development in the Italian Peninsula during the Middle Pleistocene and sheds new light on the role played by the most marked glacial periods in determining the history of tree taxa.
... The taxonomy follows World Register of Marine Species (Boxshall et al., 2015). Ecological categorization of each species was determined following Pérès and Picard (1964); Parenzan (1970); Fretter and Graham (1976, 1978a,b, 1982); Tebble (1976); Pérès (1982) and Riedl (1991). Status code and preservation code are two qualitative indexes estimated following Basso and Corselli (2007). ...
... The genera Belgrandiella and Graliana were also compared genetically with the genus Hydrobia (cf. Haase, 1993b), which is clearly distinct in anatomy and ecology (Fretter & Graham, 1978; Falniowski, lgBT). The frequencies of 121 aileles at 2l loci are listed in Appendix 2. Two genera share foui alleles in each case. ...
Article
Seven species of the genus Belgrandiella A. J. Wagner, 1928 (sensu lato), from Austria and Italy are described in detail. The genus Graziana Radoman, 1975, is redefined on a newly discovered character of the stomach, the shield caecum. This is remarkable, since hydrobiid genera are usually defined by characters of the reproductive system. Two species, B. pelerei sp. nov. and G. klagenfurtensis sp. nov., are new to science. Allozyme electrophoresis of ten populations of these seven species revealed an unusual lack of variability within each population. This is explained as a consequence of the presumed mode of dispersal of these crenobiontic snails, i.e. aerial transport with insects. Genetic distances between conspecific populations and congeneric species fall within the expected range. The only exception is the genetic identity of G. klagenfurtensis and G. lacheineri Küster, 1853. This identity is probably due to the recent origin of G. klagenfurtensis, whose area was covered with ice during the Würm glaciation. The high distance values between Belgrandiella and Graziana justify the generic separation based on a character of the digestive system. This is also confirmed through the comparison with three species of the genus Hydrobia Hartmann, 1821, which differs in all systematically relevant aspects from the other two genera.
... une seconde étape de notre travail a donc consisté à étudier les stigmates liés à l'utilisation de ces coquilles afin de séparer les parures des tests percés accidentellement. (Fretter & graham, 1978). ...
... In general, very little is known about the biology of freshwater hydrobiids in contrast to their brackish water relatives of the genus Hydrobia Hartmann, 1821 (e.g., Fretter & Graham, 1978;Lassen & Clark, 1979;Davis et al., 1989; and literature cited therein), and Potamopyrgus antipodarum Gray, 1843 (e.g., Duncan & Klekowski, 1967;Winterbourn, 1969;Ponder, 1988;Jacobsen & Forbes, 1997;Jokela et al., 1997; and literature cited therein), which tolerates a wide range of salinities from brackish to freshwater. Bythinella dunkeri (Frauenfeld, 1856) is the only species of hydrobioid spring snails in which feeding was systematically investigated (Oswald et al., 1991;Brendelberger, 1992Brendelberger, , 1995. ...
Article
Two new species of the family Hydrobiidae from Austria are described. One belongs to the genus Belgrandiella A. J. Wagner, 1928, the second is allocated to Bythiospeum Bourguignat, 1882. The crenobiontic Belgrandiella species is characterized by one autapomorphic character state of the genital system and by a unique combination of states which are shared with other species. The second species, a stygobiont, is tentatively attributed to Bythiospeum, because its description is based only on shell characters. Both species are known from very restricted ranges corresponding to the distributional pattern of their congeners. In addition, data of 13 abiotic parameters measured over a period of more than 5 years in the springs where the new species were found are presented. The values of these parameters are characteristic for natural, carbonate brooks. Contamination with fecal bacteria suggests influence through agriculture or may be caused by feces of mammals. Chemically, agriculture and forestry appear to have no significant impact on the springs investigated.
... Thiele (1927) earlier had observed a strongly asymmetrical osphradium, similar to that in Pomatias, in the assimineid genus Pseudocyclotus. In Assiminea infima Berry, the left side of the pallial floor is densely ciliated (Hershler, 1987), while in Assiminea grayana Fleming two ciliated ridges or tracts are present, one on the mantle floor and one on its roof (Fretter and Graham, 1978). Two opposed ciliary tracts in the pallial cavity have been advanced as a synapomorphic character of the Heterobranchia (Haszprunar, 1985c). ...
Article
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This book presents a synthesis of current knowledge and research on the biology of terrestrial gastropod molluscs, which are of importance to human societies as food, medicine, crop pests, vectors of parasites, and as tools, personal ornamentation and currency in trade. It covers the morphology, phylogeny and systematics, structure and function of the various organ systems, feeding behaviour, life history strategies, behavioural ecology, population and conservation genetics, and soil biology and ecotoxicology of the terrestrial molluscs.
... It is usually assumed that protoconch 1 is formed inside the egg, and protoconch 2 in the larval stage which may occur in the egg or may be truly planktic. A planktotrophic veliger larval stage is indeed known for Assiminea grayana Fleming, 1828, which has a very small nucleus and a protoconch 2 (Fretter and Graham Brandt (1974), Fretter and Graham (1978), Fukuda and Ponder (2003), Janssen (2007), Kadolsky (2015), Kowalke (1998), van Aartsen (2008) and new data Name: Referring to the Arabian origin. ...
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Terrestrial and aquatic gastropods from the upper Eocene (Priabonian) Zalumah Formation in the Salalah region of the Sultanate of Oman are described. The assemblages reflect the composition of the continental mollusc fauna of the Palaeogene of Arabia, which, at that time, formed parts of the southeastern Tethys coast. Several similarities with European faunas are observed at the family level, but are rarer at the genus level. These similarities point to an Eocene (Priabonian) rather than to a Rupelian age, although the latter correlation cannot be entirely excluded. At the species level, the Omani assemblages lack any relations to coeval faunas. This suggests the possible presence of a distinct biogeographic province during the Palaeogene or may simply reflect the extremely sparse non-marine fossil record of the Eocene in the Tethys region. The occurrence of the genera Lanistes, Pila, and Gulella along with some pomatiids, probably related to extant genera, suggests that the modern African–Arabian continental faunas can be partly traced back to Eocene times and reflect very old autochthonous developments. In contrast, the diverse Vidaliellidae went extinct, and the morphologically comparable Neogene Achatinidae may have occupied the equivalent niches in extant environments. Carnevalea Harzhauser and Neubauer nov. gen., Arabiella Kadolsky, Harzhauser and Neubauer nov. gen., Pyrgulella Harzhauser, Kadolsky and Neubauer nov. gen., Salalahia Kadolsky, Harzhauser and Neubauer nov. gen., Omanitopsis Harzhauser and Neubauer nov. gen., Arabicolaria Harzhauser and Neubauer nov. gen., Pacaudiella Harzhauser and Neubauer nov. gen., Goniodomulus Harzhauser and Neubauer nov. gen., Eoquickia Harzhauser and Neubauer nov. gen., Omanillya H. Nordsieck nov. gen. and Omanifera H. Nordsieck nov. gen. are introduced as new genera. Pila neuberti Harzhauser and Neubauer nov. sp., Arabiella arabica Kadolsky, Harzhauser and Neubauer nov. sp., Pyrgulella parva Harzhauser, Kadolsky and Neubauer nov. sp., Salalahia thaytinitiensis Kadolsky, Harzhauser and Neubauer nov. sp., Omanitopsis vandammei Harzhauser and Neubauer nov. sp., Procyclotopsis eocenica Harzhauser and Neubauer nov. sp., Palaeocyclotus kuehschelmi Harzhauser and Neubauer nov. sp., Arabicolaria arabica Harzhauser and Neubauer nov. sp., Pacaudiella omanica Harzhauser and Neubauer nov. sp., Pacaudiella flammulata Harzhauser and Neubauer nov. sp., Goniodomulus solaniformis Harzhauser and Neubauer nov. sp., Cerastus hyznyi Harzhauser and Neubauer nov. sp., Omanillya lunellifera H. Nordsieck nov. sp., Omanillya costellata H. Nordsieck nov. sp., and Omanifera euclista H. Nordsieck nov. sp. are described as new species.
... Es sei hier nur auf Tr uncatella subcylindrica verwiesen (A bb. [26][27][28]: in gängiger taxonomi­ scher Auffassung sind gerippte Formen mit Außenwulst und glatte Formen ohne Außenwulst konspezifisch (FRETTER & GRAHAM 1978). Bei Nystia pupiniformis ist die Protokonchgröße gleich der von N. pseudoplicata, und der Apex noch schlan­ ker; die Axialrippen sind mehr oder minder rudimentär. ...
... The larval shell morphology has been extensively studied for gastropods from various environments (e.g. Fretter & Pilkington, 1971;Fretter & Graham, 1978;Young, 2002;Kowalke, 2006). Usually, planktotrophic larvae show shells with a division into protoconch I and protoconch II; the former develops within the egg capsule and is frequently without sculpture or ornamentation, while the latter forms after hatching and is often sculptured. ...
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http://mollus.oxfordjournals.org/cgi/content/abstract/eyv011? ijkey=wN63ugdccwM8mx4&keytype=ref
... The larval shell morphology has been extensively studied for gastropods from various environments (e.g. Fretter & Pilkington, 1971;Fretter & Graham, 1978;Young, 2002;Kowalke, 2006). Usually, planktotrophic larvae show shells with a division into protoconch I and protoconch II; the former develops within the egg capsule and is frequently without sculpture or ornamentation, while the latter forms after hatching and is often sculptured. ...
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The organogenesis, histogenesis and growth of larvae of the fighting conch Strombus pugilis (Linné, 1758) were studied over a period of 30 d after hatching in laboratory culture. Early development of S. pugilis was examined by light and scanning electron microscopy. Rearing was conducted at 27 ± 1 °C. Veligers were reared at 200 larvae l−1 in 4-l containers. Larvae were fed with the microalgae Isochrysis galbana and Nanochloropsis oculata at a concentration of 1,000 cell l−1. The protoconch at hatching measured 212 ± 12.14 μm in length and the shell reached 1,100 ± 29.11 μm 29 d after hatching. Development characteristics are described from hatching to settlement. Newly hatched veligers possess two velar lobes, a larval shell consisting of 1.5 whorls, eyespots and a single right tentacle. Late veligers (5-d old larvae) have four velar lobes and two shell whorls and the left tentacle appears. Pediveligers show a functional adult heart at 11 d. Crawling behaviour and settlement were observed from 27 to 31 d. Plantigrades were observed after 29 d, when a functioning proboscis is observed and the velar lobes are lost. This study will facilitate the identification of gastropod larval shells in the plankton and of juveniles in the meiobenthos and will aid aquaculture of Strombus species.
... Specimens were preserved in 90 -100% ethanol. All of the analysed snails closely conformed to P. antipodarum in shell and anatomical details (Fretter & Graham, 1962, 1978. Voucher material was deposited in the collection at the National Museum of Natural History, Smithsonian Institution (USNM). ...
... It occurs most frequently on a hard bottom, which was confirmed in our study, but it also created large populations on sandymuddy bottoms. This species is known from habitats with macrophytes and also as a species that avoids sites that are shaded by trees (Fretter and Graham 1978;Zaranko et al. 1997;Alonso and Castro-Díez 2008). In the Ruda River, it occurred on macrophytes but at sites with full insolation. ...
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The progressive degradation of aquatic ecosystems and ecohydrological role of rivers is one of the most important global environmental issues. The loss of the ability of rivers to self-purify waters due to the disturbances of river continuity cause a lack of biological life in parts of rivers or even in an entire river. The appearance of alien species in degraded aquatic environments is an increasingly common phenomenon and constitutes one of the threats to biodiversity. The aim of the study was to evaluate the possible impact of alien species Potamopyrgus antipodarum (Gray, 1843) and Gammarus tigrinus (Sexton, 1939) on native invertebrates as well as the influence of environmental factors on the occurrence benthos fauna including also alien species. The study conducted in industrial area, in the River Ruda (Poland), showed that at the sites at which the occurrence of the two alien species was observed, the density of native benthos and diversity decreased significantly. CCA analysis showed that non-native species occurred in fast water velocity and that their presence was associated with high values of conductivity, hardness, and a high chloride content. The arrival of new species from other geographical areas is one of the factors that influences the species balance in native aquatic fauna. The number of alien species in freshwater ecosystems probably will increase in the future as new aliens are moved outside of their native ranges.
... Gravid individuals incubate shelled larvae throughout the year and they are a continuous release of larvae. The ability to produce young throughout the year has also been mentioned in Sphaerium and Musculium (Mackie, 1979) and in populations of the gastropod Potamopyrgus antipodarum (Gray), from New Zealand, Australia and Europe (Winterbourn, 1970;Fretter and Graham, 1978;Schreiber et al., 1998). However, in pisidiid bivalves this reproduction strategy is rather unusual. ...
Article
The dam reservoirs of the Upper Rhone were drained every three years until 2003, and the water level of the Villebois reservoir was lowered by 1.5 m. This resulted in considerable drying of its littoral habitats and the disappearance of the abundant macro-invertebrates that live in them. This study investigates the response to this drying disturbance of bivalve populations and especially of the life history traits of the two potamic species, Pisidium moitessierianum and Pisidium supinum. The low density of these bivalves observed during the months following the drying of May 2003 until spring 2004 shows that the contribution of drift in population recovery was very limited during this period. Due to the faster turnover of its cohorts and a higher increase in litter size in 2004, P. moitessierianum once again dominated bivalve communities from 2005 onwards. In the Villebois reservoir recovery of bivalve communities in terms of structure and density was total three years after the drying of 2003. Observations suggest an increase in litter size and continuous recruitment: the reproductive strategy adopted by these bivalves represent response to the fall in numbers on the one hand, and to considerable magnitudes of temperature and flow rates on the other hand, enabling the rapid adjustment of populations to drying disturbance and variations in environmental conditions. Taking into account the response of bivalve populations to this event, its effects are comparable to those of a supra-seasonal drought (Lake, 2003, Freshw. Biol., 48, 11611172).
... In fact, in the northern sector, cs deposits yielded a molluscan fauna characterised by Hydrobiidae and Cerastoderma; on the other hand, in the southern sector, lagoon deposits are dominated by Hydrobiidae. The cockle Cerastoderma glaucum is a strictly paralic species which thrives in a salinity range between 18‰ and 37‰ (VATOVA, 1981); the Hydrobiidae live in waterbodies with a salinity of 2-34‰, but normally prefer a narrower range, 6-25‰ (FRETTER & GRAHAM, 1978). The different feeding habits of C. glaucum (a filter-feeding) and Hydrobiidae (herbivores or surface detritivores, burrowers), suggest that varying abundances recorded for these taxa reflect salinity fluctuations (CALDARA & PENNETTA, 1992). ...
Article
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Along the Apulian Adriatic coast, in a cliff south of Trani, a succession of three units (superimposed on one another) of marine and/or paralic environments has been recognised. The lowest unit I is characterised by calcareous/siliciclastic sands (css), micritic limestones (ml), stromatolitic and characean boundstones (scb), characean calcarenites (cc). The sedimentary environment merges from shallow marine, with low energy and temporary episodes of subaerial exposure, to lagoonal with a few exchanges with the sea. The lagoonal stromatolites (scb subunit) grew during a long period of relative stability of a high sea level in tropical climate. The unit I is truncated at the top by an erosion surface on which the unit II overlies; this consists of a basal pebble lag (bpl), siliciclastic sands (ss), calcareous sands (cs), characean boundstones (cb), brown paleosol (bp). The sedimentary environment varies from beach to lagoon with salinity variations. Although there are indications of seismic events within the subunits cs, unit II deposition took place in a context of relative stability. The unit II is referable to a sea level highstand. Unit III, trangressive on the preceding, consists of white calcareous sands (wcs), calcareous sands and calcarenites (csc), phytoclastic calcirudite and phytohermal travertine (pcpt), mixed deposits (csl, m, k, c), sands (s) and red/brown paleosols (rbp). The sedimentation of this unit was affected by synsedimentary tectonic, attested by seismites found at several heights. Also the unit III is referable to a sea level highstand. The scientific literature has so far generally attributed to the Tyrrhenian (auct.) the deposits of Trani cliff. As part of this work some datings were performed on 10 samples, using the amino acid racemization method (AAR) applied to ostracod carapaces. Four of these samples have been rejected because they have shown in laboratory recent contamination. The numerical ages indicate that the deposits of the Trani cliff are older than MIS 5. The upper part of the unit I has been dated to 355 +/- 85 ka BP, thus allowing to assign the lowest stromatolitic subunit (scb) at the MIS 11 peak and the top of the unit I at the MIS 11-MIS 10 interval. The base of the unit II has been dated to 333 +/- 118 ka BP, thus attributing the erosion surface that bounds the units I and II to the MIS 10 lowstand and the lower part of the unit II to MIS 9.3. The upper part of the unit II has been dated to 234 +/- 35 ka BP, while three other numerical ages come from unit III: 303 +/- 35, 267 +/- 51, 247 +/- 61 ka BP. At present, the numerical ages cannot distinguish the sedimentation ages of units II and III, which are both related to the MIS 9.3-MIS 7.1 time range. However, the position of the units, superimposed one another, and their respective age, allows us to recognise a subsidence phase between MIS 11 and MIS 7, followed by an uplift phase between the MIS 7 and the present day, which led the deposits in their current position. This tectonic pattern is not in full agreement with what is described in the literature for the Apulian foreland.
... At La Vergne, the 3297 shells were identified using reference works in marine biology (Fretter and Graham 1976;1978;1981;1984;Poppe and Goto 1991;1993) and a reference collection (the Gruet comparative collection). At least fifteen species have been identified: one scaphopod, seven gastropods and seven bivalves (Fig. 2). ...
Chapter
More than three thousand perforated shells were discovered in association with Early Mesolithic burials (ca. 8500-8000 cal BC) at La Vergne (Charente-Maritime, western France). Despite the status of this excavation (an archaeological rescue operation), the locations of all the artefacts were recorded three dimensionally. This initial information is fundamental to understanding how the shells were associated with the individual human bodies. The determination of species is also important in showing where and how these shells were gathered. The condition of their surfaces allows those marks related to marine erosion, animal and anthropogenic perforations to be distinguished. Identification of use-wear and the degree of wear, in combination with spatial information, permits the reconstruction not only of body ornaments but also of objects associated with them during burial. This paper presents an overview of the different stages in the study of the ornaments from La Vergne, from the excavation to the reconstruction of the original position of the shells.
... Thiele (1927) earlier had observed a strongly asymmetrical osphradium, similar to that in Pomatias, in the assimineid genus Pseudocyclotus. In Assiminea infima Berry, the left side of the pallial floor is densely ciliated (Hershler, 1987), while in Assiminea grayana Fleming two ciliated ridges or tracts are present, one on the mantle floor and one on its roof (Fretter and Graham, 1978). Two opposed ciliary tracts in the pallial cavity have been advanced as a synapomorphic character of the Heterobranchia (Haszprunar, 1985c). ...
Article
The La Vergne site form an exceptional funerary assemblage for recent prehistory on the Atlantic coast of Europe. The only comparative sites are those discovered on the Breton islets of Téviec and Hoëdic (Péquart et al. 1937, Péquart and Péquart 1954), notably on account of the abundance of ornamental elements sometimes presented as the remains of a disappeared “language” (Taborin, 2004). At La Vergne, uncertainty persists as to the presence of possible contemporaneous settlement levels (Courtaud et al. 1999, p. 289). Three burials correspond to as many distinct pits (fig. 1). The available radiocarbon dates are all centred around 8300 BC (Duday et al. 1998). Carbon and nitrogen isotope studies suggest a predominantly land-based diet, in keeping with the inland location of these burials (Schulting et al. 2008). The objects associated with these different individuals, however, contain a very large quantity of seashells. Among these burials, pit 3 yielded the human bones of a woman associated with the remains of a foetus near term, and those of a child in a seated position (Duday and Courtaud 1998). The infill of pit 7 contains the bodies of two individuals lying on their left side in a very contracted position, as well as the remains of a child, covered by several burnt human bones (Duday and Courtaud 1998). The excavators specify that some of these deposits “must correspond to offerings rather than ornaments worn by the deceased” (Duday and Courtaud 1998, p. 30). The southern half of pit 10 contains two aurochs’ horns from kills, and to the north the body of a very robust man lies on his left side, with the skeleton of a child against his shoulder. In all cases, these are simultaneous primary burials, in a sealed space, sometimes associated with large deposits of ochre. The study of prehistoric adornment has too often been limited to considering each element separately. At La Vergne, the rapid sealing of the pits, highlighted by anthropologists in the field, is a major asset for the study of the assemblages. Traces of wear sometimes attest to how ornamental items were suspended or worn, and the spatial distribution of the objects is not the same in each grave, which is conducive to proposing a reconstruction of the adornment associated with each of the deceased.
Article
Abstract The Mesolithic burials of La Vergne delivered 3 297 marine shells, mostly from marine environments and collected on a foreshore located at less than 30 kilometers away. Most of the shells are pierced, through an anthropic action when nature had not already done its work. The traces of wear, for example the place of each item in the grave, make it possible to identify many perishable objects that participated in the staging of the funeral, as well as some elements of body adornment. After describing both, the search for the shells on the beach, their use and their deposition with the mortal remains, the exceptional nature of this discovery is discussed in a broader context, geographically on a Western European scale, and chronologically by comparing them locally to some of the graves of the region’s first farmers, who delivered many pieces of adornment made from this same raw material. Résumé en français Les sépultures mésolithiques de La Vergne ont livré 3 297 coquilles, pour la plupart d’origine marine et recueillies échouées sur un estran alors situé à moins de 30 kilomètres. La plupart des coquilles sont percées, par le biais d'une action anthropique lorsque la nature n'avait pas déjà fait son œuvre. Leurs traces d'usures, comme la place de chacune de ces coquilles dans les trois principales sépultures, permettent de restituer nombre d'objets en matière périssable qui ont participé à la mise en scène des funérailles, ainsi que quelques éléments de parure corporelle. Après avoir décrit à la fois, la recherche des coquilles sur la grève, leur utilisation et leur dépôt avec les dépouilles, le caractère exceptionnel de cette découverte est ensuite discuté dans un cadre plus large, sur le plan géographique à l'échelle de l'Europe occidentale, et sur le plan chronologique en les comparant localement à quelques tombes des tous premiers agriculteurs de la région qui ont livré de très nombreuses pièces de parure façonnées à partir de la même matière première.
Chapter
This chapter deals with the systematic aspects of the molluscan and barnacle assemblages found in the Breiðavík Group in North Iceland. They are primarily based on collections and field work carried out more or less each year since 1972. They are also based on the collections of the Institute of Natural History (Museum) in Reykjavík, the Geological Museum in Copenhagen, the collection of the farmer Jóhannes Björnsson in Ytri-Tunga on TjörnesTjörnes, and the collection of Már Vilhjálmsson in Icelandic Institute of Natural History. We report 14 species of prosobranch gastropods, 2 opisthobranch gastropod species, 29 species of bivalves, and 2 species of barnacles have been identified from the Breiðavík Group. In total, it is a question of 45 species of molluscs and 2 barnacle species. Two of the mollusc species are new for the Breiðavík Group. Each species is illustrated on plates, and variation in shape is demonstrated where the material makes it possible. The distribution, recent or fossil, of the various species is recorded, and pertinent ecological and biological features are discussed. The larval development of the species is also recorded as their ability to migrate is significantly depending on the pelagic larval development. The Early Pleistocene Breiðavík fauna marks the transition of the warm temperate Tjörnes faunas to the subarctic-arctic faunas at the onset of the Pleistocene.
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