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The study of the Neogene sequences outcropping in the La Purisima area, Baja California Sur, Mexico, has demonstrated the presence of regional unconformities separating the main sedimentary bodies. On the basis of stratigraphic and structural analyses, we propose a new statigraphic framework in terms of depositional sequences. The Lower Sedimentary Sequence (San Gregorio Formation Auctorum) is mainly composed of silicized shales with phosphatic nodules and subordinate tuffìtes. The sequence is heavily deformed at several sites, and shows N-S trending folds, thrusts and normal faults. The Middle Sedimentary Sequence (Isidro Formation and lowermost Comondù Formation Auctorum) consists of shallow marine fossiliferous sandstones with cineritic beds, capped by a thick fan of volcaniclastic sandstones. Small E-W trending thrusts and folds are associated to huge NNW-SSE and NW-SE open folds. The Upper Sedimentary Sequence is made of sub- horizontal sandstones and conglomerates probably representing the distal facies of the enormous alluvial fans of the Comondù Formation. Coquinoid limestones associated with volcaniclastic sandstones and conglomerates have been observed in between the lower and middle sequences, and are supposed to constitute a further allostratigraphic unit. The combined analysis of the stratigraphic and tectonic evidences is consistent with complex active wrenching along the Pacific margin., Rivista Italiana di Paleontologia e Stratigrafia (Research In Paleontology and Stratigraphy), V. 97, N. 3-4

The surgical option which should be reserved for patients with BRCA1/2 mutation and breast cancer diagnosis is still debated. Several aspects should be considered before the surgical decision-making: the risk of ipsilateral breast recurrence (IBR), the risk of contralateral breast cancer (CBC), the potential survival benefit of prophylactic mastectomy, and the possible risk factors that could either increase or decrease the risk for IBR or CBC. Breast conservative treatment (BCT) does not increase the risk for IBR in BRCA mutation carriers compared to non-carriers in short term follow-up; however, an increased risk for IBR in carriers was observed in studies with long follow-up. In spite of the increased risk for IBR in patients who underwent BCT than patients with mastectomy, no significant difference in breast-cancer specific or overall survival was observed by local treatment type at 15 years. Patients with BRCA mutation had a higher risk for CBC compared with non-carriers and BRCA1-mutation carriers had an increased risk for CBC compared to BRCA2-mutation carriers. Bilateral mastectomy is intended to prevent CBC in BRCA mutation carriers, however, no difference in survival was found if a contralateral prophylactic mastectomy was performed or not. For higher-risk groups of BRCA mutated patients, a more-aggressive surgical approach may be preferable, but there are some aspects that should be considered in the surgical decision-making process. The use of adjuvant chemotherapy and performing oophorectomy are associated with a decreased risk for IBR. When considering the risk for CBC, three risk factors were associated with significantly decreased risk: the use of adjuvant tamoxifen, performing oophorectomy and older age at first breast cancer diagnosis. As a result, we could identify a group of patients that might benefit from a more aggressive surgical approach (unilateral mastectomy or unilateral therapeutic mastectomy with concomitant contralateral prophylactic mastectomy). For women with BRCA mutations candidate to mastectomy, preservation of the nipple-areola complex (NAC) may be highly important due to the generally younger age at time of surgery. Concerning the oncological safety, nipple sparing mastectomy (NSM) is an acceptable option, with no evidence of compromise to oncological safety at short-term follow-up. The evaluation of surgical treatment in breast cancer patients with BRCA 1/2 mutation, should include several issues, namely the current evidence of adequate oncological safety of BCT in BRCA mutated patients; the increased risk for CBC especially in BRCA1 carriers; the feasibility on NSM with a greater patient's satisfaction for cosmetic results with no evidence of compromised oncological safety and, finally, the awareness that breast radiotherapy might increase the risk of complications in a possible subsequent mastectomy with immediate breast reconstruction.

Gastropods and bivalves recently recovered from offshore soft bottoms in the Northern Gulf of Thailand, along with those obtained from the Ban Laem Phak Bia sand spit (Phetchaburi Province) and the Pak Phanang Bay (Nakhon Si Thammarat Province) are described and discussed. Mollusk assemblages in the Gulf appear to be similar to those described in previous papers by the present authors, while the Pak Phanang ones reflect a confined environment which is undergoing heavy modifications. Galeommatoidea, Tellinoidea, Triphoroidea, Conoidea and Pyramidelloidea are the most diverse groups. This paper covers 150 species, of which 3 are proposed as new; 53 remain unidentified and might be, at least partly, undescribed by previous workers. The species treated are complemented with taxonomic remarks when necessary and with information on respective ecological requirements if available. All species are illustrated. A list of references to the mollusk fauna of the Indo-Pacific Region is also given.

The pyramidelloidean gastropods newly collected from one stratigraphic section and two spot localities in the Rembang anticlinorium (Middle Miocene, northeastern Java) are described and those of various ages in the collections of the Naturalis Biodiversity Center in Leiden are reviewed. A total of 111 species are covered in this paper; another 22 taxa dealt with by previous authors, of which the material was not available, are briefly commented on in an appendix. The “Rembangian” (Middle Miocene) assemblage consists of 89 species. Four are identified as formerly described species, namely Leucotina speciosa (Adams), Megastomia regina (Thiele), Exesilla dextra (Saurin) and Exesilla splendida (Martin); 52 are proposed as new; most of the others almost certainly represent previously undescribed species, but cannot be named because of inadequate material. Parodostomia jogjacartensis (Martin), Parodostomia vandijki (Martin) and Pyramidella nanggulanica Finlay, described from the Eocene deposits of Java, seem to be restricted to that epoch. The Neogene fauna appears to be composed almost entirely of extinct species. Only Leucotina speciosa (Adams), Megastomia regina (Thiele), Longchaeus turritus (Adams), Pyramidella balteata (Adams), Exesilla dextra (Saurin) and Nisiturris alma (Thiele) are still present in modern Indo-West Pacific faunas. Most Neogene species seem to be endemic of the Indonesian Archipelago; relationships with other West Pacific fossil faunas have been noted for only a few taxa. The relevance of shell characters in generic recognition, namely the protoconch type, the course and/or the inner lirations of the outer lip, and the sculpture (when present), are significant characters. None of them is genus-diagnostic in itself, but their combination distinguishes the various genera. On this basis, genera are revised and include only those species sharing the relevant characters of their respective type species. The new genera Bulimoscilla, Nisipyrgiscus, Turbolidium and Bulicingulina are introduced.

The present paper examines the molluscan and/or echinoid assemblages recovered from two lithostratigraphic units (Piedras Rodadas Sandstone and Arroyo de Arce Norte Sandstone) outcropping in the Pliocene Loreto Basin, Baja California Sur, Mexico. Ten biofacies have been identified, i.e. Trachycardium procerum-Trachycardium senticosum Biofacies, Chione compta-Transennella modesta Biofacies, Laevicardium elenense-Chione kelletii Biofacies, Xenophora sp. 1-Strombus subgracilior Biofacies, Crassostrea californica osunai Biofacies, Myrakeena angelica Biofacies, Vermetid-Nodipecten Biofacies, Argopecten abietis abietis Biofacies, Aequipecten dallasi Biofacies and Encope Biofacies. The first four biofacies have been defined on the basis of statistical analyses (cluster analysis, MDS). The other six, which are monospecific or definitely low-diversity, were already identified during field work. The deduced paleoecological bearing of biofacies, largely relying upon the comparison to their closest modern counterparts, provides the basis for the paleoenvironmental reconstruction. The latter also considers sedimentological evidence and is framed within the tectonic and sedimentary context recently proposed by American workers. Biofacies point toward environments differing in terms of substrate texture, presence/absence of vegetal cover, energy level, variously distributed within the low tide mark-40 m bathymetric range., Rivista italiana di Paleontologia e Stratigrafia, Vol 104, No 2

Fourteen pectinid and oyster species from the Pliocene Loreto Basin (Baja California Sur, Mexico) are recorded and discussed with regard to their relationships with closely related taxa. The whole assemblage points toward a Pliocene age. Aequipecten dallasi and Argopecten abietis abietis resulted to be the most useful biostratigraphic taxa, being restricted to Pliocene. The bulk of the considered species were confined within southern regions during the Pliocene. Crassostrea californica osunai is likely to have been endemic of Baja California Sur. Pectinids and oysters appear to have inhabited fine to coarse shallow infralittoral bottoms wave- or current-nfluenced. The environmental energy was the main factor controlling presence/absence of species. Finally, a unusual vermetid-Nodipecten association is described and interpreted in terms of paleoenvironmental meaning., Rivista Italiana di Paleontologia e Stratigrafia (Research In Paleontology and Stratigraphy), V. 100, N. 1

Faunal examination is made of 4 samples, 2 from the Recent Ban Laem Phak Bia sand spit, and 2 from the Holocene sand body of Ban Bang Ket. Fossil and modern assemblages are compared on the basis of overall composition, taxa abundances, and of autoecological investigation on life habit, substrate preference, feeding type, depth range and ecological meaning of the identified species. The Holocene assemblage of Ban Bang Ket, compared to the Recent one of Ban Laem Phak Bia, 1) exhibits generally similar overall composition and ecological structure, 2) contains much of the dominant species characterizing the modern assemblage, and 3) includes all taxa that are members of the living molluscan community. On this basis, the molluscan assemblage of Ban Bang Ket results to be the Holocene counterpart of the modern one of Ban Laem Phak Bia, and reflects the same environmental conditions recorded for the latter. Thus, the sand body near Ban Bang Ket is interpreted as a Holocene equivalent of the sand spit of Ban Laem Phak Bia., Sezione di Museologia Scientifica e Naturalistica, 2005: Volume Speciale

We studied the sclerobiont community associated with organogenic and lithic cobbles from soft bottoms in the Khao Lak coastal area (Andaman Sea) that was damaged by the 2004 tsunami. The 15 cobbles examined originate from grab and hand sampling carried out in the years 2006 and 2007 in the depth range of 4.6–15.2 m. A rich endo- and epibenthos was identified, mainly consisting of algae, foraminifers, sponges, cnidarians, polychaetes, bryozoans and bivalves. Associations on each examined cobble show similarities in composition and structure being characterized by a few dominant groups. Differences were noted in the degree and pattern of colonization, distinguishing for each cobble an upward and a downward side at the time of sampling. The mean total coverage is 15.09% being higher on the upper sides (17.4%) compared to the lower sides (12.8%). Calcareous algae, bivalves and sponges prevail on upper sides, while bryozoans prevail on lower sides. The sclerobionts distribution allowed to infer the orientation of cobbles on the seafloor during colonization. Major colonization values, exceeding 30% coverage, were observed on organogenic cobbles located in the proximity of reefs or collected from below 12 m of water depth. Conversely, cobbles from the shallowest stations result poorly colonized, independently of their composition. The water turbidity and wave motion as a possible cause of the observed distributions were discussed. The Khao Lak cobble community seems to be largely unaffected by the tsunami event, as suggested by the estimated biodiversity, abundance and coverage of sclerobionts.

This paper reports a case history concerning the use of benthic molluscan thanatocoenoses as a record of living associations that preceded the modern ones. The investigated area encompasses the tidal flats and upper infralittoral bottoms facing the coastline of Phetchaburi province, approximately 150 km southwest of Bangkok, in the Northern Gulf of Thailand. Radiocarbon dating of molluscs in thanatocoenoses reveals that they have been affected by nuclear activities in the 1960s. The multivariate statistical treatment of faunal abundance data from 55 stations delineates 7 thanatofacies. The first one is widespread throughout the upper infralittoral zone and is largely dominated by Nuculana (Jupiteria) puellata, Timoclea (Chioneryx) scabra and Decorifer sp. Thanatofacies 2, recovered at a single station in the inner tidal flat, is dominated by Scapharca indica, Cerithidea cingulata and Cycladicama oblonga. Thanatofacies 3, also within the tidal flat at more sandy locations, is dominated by Corbula (Caryocorbula) lineata, Decorifer sp. and Mactra (Mactra) luzonica. The fourth is another typical intertidal thanatofacies, dominated by Pitar (Costellipitar) manillae, Anadara granosa and Arcopagia yemenensis. Thanatofacies 5 and 6 appear to be intertidal ecotones, representing different transitional aspects, between the infralittoral thanatofacies 1 and the strictly intertidal thanatofacies 4 and 5. The upper infralittoral thanatofacies 7 denotes sedimentary instability. The living associations obtained at the same locations appear to be markedly depleted in both species richness and total number of specimens, if compared to the co-occurring thanatofacies. The whole sea-bed area apparently underwent a dramatic decrease in benthic molluscan biodiversity during the last decades. This change seems to be related primarily to the intensive trawling in shallow water, practiced by local coastal villagers, possibly associated to shrimp farming effluent and sewage from coastal human settlements that affect the water quality.

The scaphopods, gastropods and some newly found bivalves recovered from the Holocene Bangkok Clay in the Lower Central Plain of Bangkok along with those obtained from modern shallow bottoms in the Phetchaburi coastal area are recorded and described. The gastropod assemblages of the Holocene Bangkok Clay appear to parallel the Recent ones recovered at sea from intertidal and shallow infralittoral, predominantly muddy substrates. Rissoidea, Muricoidea, Conoidea and Pyramidelloidea are the most diverse groups, with species that often occur abundantly. This paper covers 336 species, of which 23 are proposed as new; 108 remain unidentified and are, at least partly, previously undescribed. The species treated are complemented with taxonomic remarks when necessary and with information on respective ecological requirements if available. Nearly all species are illustrated in the plates. A list of references to the mollusk fauna of the Indo-Pacific Region is also given.

The present paper examines Holocene and Recent molluscan associations (or assemblages) of Thailand and identifies pairs, each including a modern association and its fossil analog. The aim is to reconstruct precisely the environmental meaning of the Holocene associations, assuming that these have dwelled the same environment of their modern counterparts. The Anadara granosa-Cerithidea cingulata assemblage records innermost muddy tidal flat conditions, with mangrove vegetation. The Alveinus ojianus-Nuculana (Scaeoleda) mauritiana association thrived in an outer tidal flat, also muddy, that experienced sedimentary instability in turbid waters. The Nuculana (Jupiteria) puellata-Chrysallida melvilli association occurred in sandy mud, at the transition between intertidal and infralittoral zones, and denotes some scouring and turbulent water. The Timoclea (Chioneryx) scabra-Arcopagia pudica association dwelled upper infralittoral bottoms of sandy mud, hardly exceeding 10 m depth. Finally, based on the relative geographic position of the fossil Nuculana (Jupiteria) puellata-Chrysallida melvilli association and of its modern analog Nuculana (Jupiteria) puellata-Pitar (Costellipitar) manillae association, a progradation rate of the tidal flat of 1.6 m/yr during the last 820 years was calculated.

Pseudocymopolia praturlonii, a new species from the Lower Cretaceous of the Marsica (Central Italy) is described.