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1.
A new species of Batillipedidae, Batillipes spinicauda, has been found in subtidal sand sediments collected in Orosei Gulf (Sardinia, Tyrrhenian Sea). The most important peculiarities of the new species are the shape of the primary clavae, lateral processes and caudal apparatus. In the same samples, B. littoralis Renaud-Debyser, 1959 and Orzeliscus belopus Du Bois-Reymond Marcus, 1952 were found.  相似文献   

2.
Abstract

The author reports the results of the herborizations carried out on the island Piana (northeastern Sardinia) located between Cape Ceraso and Cape Coda Cavallo. The flora consists of 250 entities distributed in 154 genera, inclusive of 54 families. The author gives information regarding the mail features of the vegetal coverage, and points out the presence of two species: Limonistrum monopetalum (L.) Boiss. and Omithoga-lum arabicum L., which are extremely rare in the little islands.  相似文献   

3.
Over the last ten years the population of the Mediterranean island of Sardinia has been object of numerous studies in the fields of anthropology and population genetics. Its insularity, central position in the Mediterranean area and rich historical past have made the island a veritable laboratory for the study and understanding of those interacting evolutionary mechanisms which determine a population's genetic structure. Indeed, from work performed at different levels on genetic structure analysis there emerges an extremely complex picture of the relationships between Sardinian and other Italian and Mediterranean populations, but also of relationships within the Sardinian population itself The diversification from Mediterranean and Italian populations can be explained by Sardinia's historical and demographic past. Internal heterogeneity can be attributed, in part, to strict isolation and the accompanying high levels of endogamy and inbreeding, and in part to the endemic presence of malaria which exerted a strong selective pressure on some characteristics; determining, for example, the differentiation between the plains and the mountain areas. Finally, an influence on Sardinia's biological history not to be neglected could be attributed to the demographic events, which triggered off phenomena of genetic drift and to cultural factors.  相似文献   

4.
Italian north Tyrrhenian regions harbour pure or nearly pure cork oak woodlands towards the NE limit of the species range and the highest proportion of the habitat on mainland Italy, but their distribution, biodiversity and conservation status are still poorly known. Focusing on the key region of Tuscany, we analysed distribution and plant species richness of these forests based on literature and original field data. The habitat covers about 5.730?ha and is strongly fragmented for natural and non-natural reasons, underscoring its relict character. Out of the 420 plant taxa recorded, 19 were listed in IUCN categories at the national or regional level. Taxonomic singularity was especially high at the genus rank. Three neighbouring areas with different soil conditions and forest structure were compared based on field surveys, sample plots and linear transects from dense stands to shrub and herbaceous communities of small openings. The Versegge site showed the highest species richness at the area-scale and the mean diversity at the plot scale, representing a key biotope for the conservation of the habitat. However, the geographic–floristic covariation between the three sites suggested that a network of small areas would be more effective than a single, large area to protect the most significant components of the local cork oak flora. The Lattaia and Terzo areas may play an important role as corridor sites between the four SCIs of the Rete Natura 2000 network including cork oak communities on the Tuscan mainland. Species richness was higher in the stands with lower cork oak basal area, and there was a significant increase in species number along transects reaching openings caused by traditional human activities. A minor anthropic disturbance of traditional type may help to preserve the fine-scale habitat heterogeneity and the biodiversity of the whole ecosystem.  相似文献   

5.
C. M. Calò  G. Vona 《Human Evolution》2005,20(2-3):99-106
San Pietro island is located in the Western Mediterranean basin, 4 km off the southwestern coast of Sardinia. It was first populated in 1738 by a founder group coming from the island of Tabarka (Tunisia). Many researchers focused their attention on the population of San Pietro, because of its peculiar linguistic, genetic and demographic features. In this paper we analyzed data on surnames, matrimonial structure and genetic polymorphisms. All the data demonstrated a strong differentiation of San Pietro population when it is compared with other Sardinian or Italian populations. This differentiation is due to the isolation that for century characterized the island. Moreover, medical researches discovered a high incidence of a rare genetic pathology: the high myopia. This mutant gene was probably present in the founder group and then the isolation and the high rate of endogamy and consanguinity, highlighted by matrimonial structure analysis, could have determined its diffusion. Finally, our results suggested that San Pietro genetic diversity is strictly associated with linguistic and cultural diversity.  相似文献   

6.
Summary Miocene syn-rift carbonate production areas are exposed in south-eastern Sardinia (Italy) along the eastern side of the Plio-Pleistocene Campidano Graben. Here the downfaulted margins of the Oligo-Miocene Sardinia rift-basin crop out with a complex alignment of smaller subbasins. Carbonate factories developed during the Aquitanian times in these tectonically controlled small depositional subbasins, where terrigenous input might be high due to the erosion of the uplifted pre-Neogene substrata. Terrigenous deposits generally acted as passive substratum for pioneer communities of rhodalgal-type (red algae, ostreids, bryozoans) and locally evolved into coral-dominated assemblages. Carbonate production areas occur on tilted, uplifted blocks as well as along basement margins. These have varying organic communities and facies characteristics strongly dependent on different environmental conditions. In footwall areas, devoid of (or with a very reduced) terrigenous supply, open foramol carbonate factories occur with aggradational-progradational stratigraphic geometries. The resulting pure calcareous successions are organized in sequences, bounded by tectonically driven discontinuity surfaces. In sectors close to the hinterland area, with a higher freshwater input and a consequent significant clastic input, coral-dominated assemblages grew during long periods of quiescence between flash floods. Repeated coral-rich communities developed on thick wedges of terrigenous debris. Carbonate facies composition and distribution were mainly controlled by local syn-sedimentary tectonics and eustasy as well as by climate. However, although the inception of the carbonate factories was presumably not synchronous, their growth represented the response to a relative regional sea level rise subsequent to episodes of significant clastic supply: the expression of an early syn-rift stage. During the Burdigalian (N6 zone) a hemipelagic cover uniformly sealed the neritic successions. This basin wide drowning event appears to correspond to the transgressive system tract of the TB2.1 cycle ofHaq et al. (1987) but it can also be interpreted as the expression of an evolved syn-rift stage passing to late syn-rift and quiescence stages. Beneath the hemipelagic cover in some areas, ?late Aquitanian-early Burdigalian deep erosive surfaces, terrigenous clastics and paleosoils have been recognized. These suggest a relative sea level fall and may relate to the global sea level drop at the TB1-TB2 boundary (seeHaq et al., 1987) or to diacronous uplift of different fault blocks.  相似文献   

7.
Vizzini A  Contu M  Musumeci E  Ercole E 《Mycologia》2011,103(1):203-208
A new species of Infundibulicybe (viz. I. mediterranea sp. nov.) is described from Sardinia based both on morphological and molecular ITS data. The species, a close ally of I. gibba, differs from the latter in the darker tinges of the basidiomata, the stipe, which is nearly concolorous with the pileus, and smaller basidiospores. Drawings of the main micro-morphological features as well as a color photograph of fresh basidiomata in situ are provided.  相似文献   

8.
ABSTRACT

This paper presents the results of a phytosociological survey carried out in the Lazio region (central Italy) to investigate the vegetation and conservation status of brackish habitats. Eighteen vegetation types are described, belonging to 8 alliances, 5 orders and 5 classes of vegetation. A new association and an association previously unrecorded in Italy, both assigned to the Frankenietalia pulverulentae, have been recognized. The occurrence of important floristic and vegetational features, and the potential for the development and restoration of typical ecological sequences suggest the implementation or the enhancement of conservation activities in all of the brackish sites surveyed.  相似文献   

9.
Microbial community thriving at shallow hydrothermal vent named Black Point, close to the Island of Panarea in the Southern Tyrrhenian Sea (Italy), was studied by microscopic, cultural and molecular methods. New strains of Bacillus and Geobacillus were isolated. Members of sulphur-oxidizing bacteria, belonging to the genera Halothiobacillus and Thiomicrospira were demonstrated by both culture-dependent and -independent methods. Genetic diversity of Bacteria was higher than that of Archaea. Bacterial 16S rRNA gene sequences from Black Point showed low levels of similarity with other yet deposited sequences, suggesting that new bacterial phylotypes are present in this site. Dominant populations of Bacteria belonged to uncultured members of Proteobacteria (mainly of the class Gammaproteobacteria), Firmicutes and Acidobacteriaceae. Primary production appeared to be supported by chemosynthetic and photosynthetic bacteria affiliated with members of Gammaproteobacteria. Most of the archaeal sequences matched those of yet-uncultivated Archaea, thus their role at this vent is not well understood.  相似文献   

10.
The genotypes of 31 autosomal short tandem repeat loci in the population of Carloforte were analyzed, these representing a linguistic and genetic isolate located on the island of Sardinia (Italy). The markers span the entire length of chromosomes 19, 20, 21 and 22. Allele frequencies and statistical parameters were presented for all loci. Observed heterozygosity ranged from 0.279 to 0.884, and polymorphism information content from 0.552 to 0.886. All but two loci showed Hardy-Weinberg equilibrium after Bonferroni correction. The 31 short tandem repeat loci examined in the present work provide additional data on the genetic structure of the Carloforte population.  相似文献   

11.
An interesting aspect of the island of Sardinia (Italy) is the wide range of genetic variability within the island itself. The variability is widened by the presence of some populations of different ethnic origin who speak a language other than Sardinian. This work deals with the study of the genetic structure of the Carloforte population which inhabits the tiny island of S. Pietro 4 km off the southwest coast of Sardinia. S. Pietro was first populated in 1738 by emigrants coming from the island of Tabarka (Tunisia) who spoke an archaic form of the Ligurian dialect. Data on genetic polymorphisms in the Carloforte population are presented and discussed in relation to some Sardinian and Italian populations. Data on demographic and matrimonial structure are also presented. The genetic analyses show the Carloforte population as being clearly separated from both Sardinians and continental Italians. The isolation of Carloforte, highlighted by language diversity, endogamy, and consanguinity levels and marriage area, supports the idea of genetic diversity linked to cultural peculiarity. © 1996 Wiley-Liss, Inc.  相似文献   

12.
Benthic foraminiferal assemblages in 127 samples, collected at water depth, ranging between 15 and 184 m on the Southern Tuscany continental shelf off the Ombrone River were analysed. Statistical analyses (Cluster and Principal Component Analysis) performed on the 48 most abundant species (>5%) and sedimentological data led to the identification of three clusters related to the size of grain sediment (sand, silt or clay). Q-mode cluster analysis singled out six groups, corresponding to six distinct foraminiferal assemblages: a typical infralittoral assemblage (15-39 m) on sandy silt, clayey silt or silty clay, dominated by Ammonia and Elphidium species, with Eggerelloides scabrus, Rectuvigerina phlegeri and Valvulineria bradyana; a second assemblage (24-78.5 m) associated with vegetated environments or sandy bottoms (Elphidium crispum, Rosalina bradyi, Asterigerinata mamilla, Neoconorbina terquemi, and Tretomphalus concinnus); a third assemblage recognised between 30 and 90 m water depth and characterised by the dominance of the opportunistic species V. bradyana (related to silty bottoms), with Bulimina marginata, R. phlegeri, Ammonia inflata and Ammonia beccarii as other common taxa; an upper circalittoral assemblage (70-100 m) on silty clays, containing B. marginata, Cassidulina carinata and V. bradyana; a lower circalittoral assemblage (95-177 m) on clayey bottoms, with B. marginata, Textularia bocki and Uvigerina mediterranea; and finally, a second lower circalittoral assemblage (104-184 m) on clayey sediments, dominated by two Uvigerina species (U. mediterranea and Uvigerina peregrina), with Sphaeroidina bulloides and B. marginata. The typical V. bradyana assemblage, characterised by relatively low diversity and high dominance, marks the most eutrophicated area running parallel to the coast. The spatial distribution of assemblages is closely associated with sea-bottom sedimentary environments and bathymetry but it is also probably influenced by the outflow of the Ombrone River. The composition, structure and distribution of V. bradyana assemblage suggest an environmental model, useful for paleogeographic reconstruction in areas characterised by a river mouth and a closed morphological setting typical of a nutrient-trap.  相似文献   

13.
The locality of Fiume Santo (Sardinia, Italy) represents the westernmost extension of endemic Oreopithecus-bearing faunas. Here we describe the rodent fauna recovered at this site, which only includes the murids Huerzelerimys oreopitheci and Anthracomys lorenzi, and the glirids Anthracoglis engesseri nov. sp. and Anthracoglis nov. sp. I. A. engesseri nov. sp. differs from Anthracoglis marinoi, the other species of this genus known so far, by its larger size, wider upper cheek teeth and more reduced accessory ridges, particularly in the upper cheek teeth. Anthracoglis nov. sp. I is only known by a single tooth and cannot be adequately characterized. The fauna seems to be a mixture of elements from the V-1, V-2 and V-3 local zones of the Baccinello-Cinigiano basin (Tuscany, Italy), with H. oreopitheci being characteristic from zone V-1 and Anthracoglis lorenzi from zone V-3. Nevertheless, a few remains of A. lorenzi have been also recovered from V-2 assemblages at Baccinello and A. engesseri nov. sp. is also recorded in Monte Bamboli, which is correlated to V-2 faunas. Accordingly, a correlation to V-2 zone of the Baccinello-Cinigiano basin is preferred. Finally, the structure and composition of the rodent assemblage is compared to those of the Tuscan sites. The Fiume Santo assemblage resembles the insular faunas of Tuscany by its low species richness, although it is more balanced. This may be related to slight chronological or environmental differences between the two areas or to the existence of a geographical barrier.  相似文献   

14.
We analyzed the archaeobotanical remains from the Mediterranean Medieval village of Geridu (Sardinia-Italy) in order: (1) to formulate hypotheses concerning different uses of woody plants; (2) to reconstruct the distribution patterns of charcoals and to compare them with the results of the archeological interpretation and (3) to describe the agricultural activities and cultural landscape around the village. In total, 29 plant taxa were identified from charcoals and 14 from carpological remains. The number of charcoals and the ubiquity of plant taxa were correlated with each other (rp = 0.735; n = 29). Only the stratigraphic units referred to as the “construction layer” in the archeological interpretation significantly differed from the other archeological contexts which were related to the life and abandonment phases of the village. Some hypotheses regarding the agricultural activities of the village were formulated on the basis of carpological remains, largely of cereals and legumes. Integration of the archeological findings with information supported by the biological archive in Geridu and with knowledge of the vegetation series allowed reconstruction of the cultural landscape, which fit with the thermo- and meso-Mediterranean climate of the area.  相似文献   

15.
ABSTRACT

The results of a synecological and syntaxonomic study of mesophilous forest coenoses, mixed or with a prevalence of Beech, in northern Latium (Roman Tuscia), are reported. The main parameters determining the distribution pattern and floristic composition of these coenoses were altitude, exposure, acclivity, asperity and ecotope. The presence of Aquifolio-Fagetum (Doronico-Fagion) at la Tolfa and in the Sabatini Mts. is confirmed, together with the autonomy of Teucrio siculi-Quercion cerridis and Lathyro-Quercion cerridis in the Cimini-Vicani and Sabatini Mts. and on the sandstone substrates of Mt. Rufeno, respectively. Variants of Polysticho-Fagetum aceretosum pseudoplatani (Galio odorati-Fagenion) with Polystichum setiferum and with Veronica hederifolia were recognized in certain parts of the Cimini and Vicani Mts. The presence of Carpinion betuli, especially with Carpino-Coryletum avellanae and the new subassociation phyllitiaetosum scolopendrii of the latter, is recognized in gullies and ravines eroded in tufo of the Vulsino and Cimino complexes.  相似文献   

16.
17.
A study of heterotrophic bacteria and vibrios adhering to the copepod Tigriopus fulvus, which lives in Ligurian coast rock pools (Tyrrhenian Sea), was carried out from November 1990 to October 1991. Heterotrophic bacteria, which were always found both free in the water and bound to the T. fulvus organisms, showed a correlation with water temperature and salinity. Vibrio alginolyticus was found free in the water and bound to T. fulvus surfaces during the warmest months. Temperature is the main factor influencing the presence of V. alginolyticus in the rock pool. Attachment of this microorganism to the copepod provides a mechanism for its extended geographic distribution.  相似文献   

18.
The occurrence of two individuals of Zu cristatus at 2 m depth in coastal waters of the Gulf of Castellamare (Tyrrhenian Sea, Italy) together with records of this rare pan‐Oceanic mesopelagic species is reported. Analyses of two mitochondrial genes (12 s and 16 s; 936 bp) revealed a 2·6% sequence divergence between Mediterranean and Pacific (Japanese) samples of the species.  相似文献   

19.
20.
Late Epigravettian postcranial human remains from the Arene Candide cave (Finale Ligure, Savona, Italy) were compared with the Neolithic sample found in the upper levels of the same site. Data on length, diaphyseal circumference and diameter of clavicle, humerus, radius, femur and tibia were collected from male specimens having all these bones. The Epigravettian sample is characterized by significantly greater tibial length, robustness and platycnemia, significantly lower circumferences in the upper limb bones and the clavicle, and a high degree of asymmetry. Variations observed in lower limb bones are those expected on the basis of the different functional requirements of a hunting and gathering economy compared to a more sedentary, food producing economy. Differences in the upper limb bones and the clavicle are less explicable. However, considering that in spite of a more slender structure, the Epigravettian bones show evidence of vigorous use, variation in upper limb could result from qualitatively different involvements.  相似文献   

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