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 Abstract Sartori, A.F., Passos, F.D. and Domaneschi, O. 2006. Arenophilic mantle glands in the Laternulidae (Bivalvia: Anomalodesmata) and their evolutionary significance. -Acta Zoologica (Stockholm) 87 : 265-272The mantle margins of several anomalodesmatans bear multicellular arenophilic glands, the mucoid secretions of which attach sand grains and other foreign particles to the outer surface of the periostracum. These glands have been recorded for many of the anomalodesmatan families and are used as a key morphological character in recent attempts to unravel the evolutionary relationships within the Anomalodesmata. The glands occur in Laternula elliptica , L. truncata , L. boschasina and L. marilina , discharging from the top of muscular papillae at the distal tip of the siphons. The secretions are laid down as threads organized in longitudinal lines along the length of the periostracum that covers the siphonal walls. This is the first record of arenophilic mantle glands in members of the Laternulidae, a finding that not only broadens our current knowledge of the family's morphology, but assists in the reconstruction of anomalodesmatan evolutionary history.

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http://dx.doi.org/10.1590/1676-06032014011514Abstract: The phytal is characterized by the formation of seaweed beds and a great diversity of associated species, the malacofauna being one of its main components. Aiming to record the species of Gastropoda associated to the brown algae Sargassum sp. C. Agardh, 1820, this study was carried out in Sã o Sebastião Channel, northern coast of Sã o Paulo, and nearby areas. A total of 13945 individuals were identified, belonging to 35 families and 62 species. Cerithiidae, Phasianellidae and Columbellidae were the most abundant families, represented by 34, 33 and 17% of the total collected individuals, respectively. Bittiolum varium (Pfeiffer, 1840) (Cerithiidae) and Eulithidium affine (C. B. Adams, 1850) (Phasianellidae) are the dominant species, followed by the columbelids Mitrella dichroa (G. B. Sowerby I, 1844), Anachis fenneli Radwin, 1968 and Costoanachis sertulariarium (d'Orbigny, 1839). Among the least abundant species, some of them may be considered as of fortuitous occurrences, while others seem to be typical in those habitats, although rare. The presence of juvenile specimens was recurrent, this indicating that the algae can function as a nursery for most of these species. The expressive values found, for both abundance and number of species, illustrate the great ecological importance of the phytal habitats for the gastropod species.

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Two new species of Rubyspira and one of Cordesia (Gastropoda: Abyssochrysoidea) are described morphologically and genetically, based on specimens collected from whale bones and wood parcels artificially implanted in the deep south-west Atlantic Ocean, at c. 1500 and 3300 m depths. Rubyspira pescaprae sp. nov. and R. elongata sp. nov. occur preferentially on whale bones. Cordesia atlantica sp. nov. is dominant on wood parcels. Distribution of Cordesia was hitherto only associated with hydrocarbon seeps off West Africa. Stable isotopes and gut content analyses were carried out to check possible trophic pathways. Both Rubyspira species are bone eaters, while Cordesia atlantica seems to rely on a wider range of food sources, including juveniles of wood-specialized xylophagid bivalves. Morphological and genetic evidence suggest that Rubyspira and Cordesia are more closely related to Abyssochrysos than to any other Abyssochrysoidea snails. In the present study, Cordesia is considered part of the family Abyssochrysidae based on molecular and morphological evidence, such as the presence of a penis and pallial tentacles arrangement.

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