Daniel C. Cavallari

The use of the terrestrial snails of the genera Megalobulimus and Thaumastus as representatives of the atmospheric carbon reservoir

In Brazilian archaeological shellmounds, many species of land snails are found abundantly distributed throughout the occupational layers, forming a contextualized set of samples within the sites and offering a potential alternative to the use of charcoal for radiocarbon dating analyses. In order to confirm the effectiveness of this alternative, one needs to prove that the mollusk shells reflect the atmospheric carbon isotopic concentration in the same way charcoal does. In this study, 18 terrestrial mollusk shells with known collection dates from 1948 to 2004 AD, around the nuclear bombs period, were radiocarbon dated. The obtained dates fit the SH1-2 bomb curve within less than 15 years range, showing that certain species from the Thaumastus and Megalobulimus genera are reliable representatives of the atmospheric carbon isotopic ratio and can, therefore, be used to date archaeological sites in South America.

A new species of Calliostoma (Vetigastropoda: Calliostomatidae) from Canopus Bank, off northeastern Brazil

In the present study, Calliostoma melliferum sp. nov. is described from Canopus Bank, a seamount located ~190 km off Fortaleza, Ceará, northeastern Brazil, at depths of 60-260 m. Shell morphology and anatomy of the soft parts are analyzed in detail with the aid of SEM and micro-computed tomography (CT-Scan) techniques. We take the opportunity to provide thorough conchological and anatomical comparisons with similar species from the Southwestern Atlantic.

Solariella quadricincta Quinn, 1992 and S. staminea Quinn, 1992 are synonyms of S. carvalhoi Lopes & Cardoso, 1958 from the SW Atlantic (Gastropoda: Solariellidae)

Solariellidae is a diverse family of small (5-20 mm) marine snails of worldwide distribution. They usually live on fine sediment to unconsolidated substrates in deep-waters of extra-tropical to tropical latitudes (Hickman 1998; Williams et al. 2013). Initially described as a subfamily of Trochidae, it has been recently raised to family level (Bouchet et al. 2005; Williams et al. 2008). The evolutionary relationships among solariellids have been extensively investigated in the light of morphological and molecular data, but the family still lacks a comprehensive taxonomic revision that reflects recent discoveries (Williams et al. 2010, 2013). The familys fossil record possibly dates back to the Campanian of Torallola, Spain (Kiel & Bandel 2001; Williams et al. 2013).

Seguenziidae (Gastropoda: Vetigastropoda) from SE Brazil collected by the Marion Dufresne (MD55) expedition

The present work deals with the vetigastropods of the family Seguenziidae collected by the Marion Dufresne (MD55) expedition in SE Brazil, reporting the occurrence of eight species. The following species have their geographical range extended: Ancistrobasis costulata, Carenzia carinata, Carenzia trispinosa, Hadroconus altus, Seguenzia elegans and Seguenzia formosa. Two new species, Halystina umberlee sp. nov. and Seguenzia triteia sp. nov., are described.

A new species of Leiostracus from Bahia, Brazil (Gastropoda, Pulmonata, Orthalicidae)

ABSTRACT. A remarkable new species of pulmonate snail was recently collected in a small Atlantic Rainforest fragment near the city of Canavieiras, state of Bahia, Brazil, an area known for a high diversity of land snails. It is described herein as Leiostracus fetidus sp. nov. and can be easily identified by its color pattern of irregular brown to black axial stripes on a white to yellow background, a reddish axial band “separating” the white peristome from the rest of the shell and a broad brown spiral band surrounding the umbilical region. Other diagnostic features include a relatively small size, a proto columellar fold and two very weak folds delimiting the basal region of the aperture. This discovery is a reminder of how little this fauna is known and also an alarm for proper conservation of these forest fragments. KEYWORDS. Atlantic Rainforest, Bulimulinae, Canavieiras, Leiostracus fetidus sp. nov., Stylommatophora. RESUMO. Uma nova especie de Leiostracus da Bahia, Brasil (Gastropoda, Pulmonata, Orthalicidae)

A new species of Nassarius (Gastropoda, Nassariidae) from Canopus bank, off Northeast Brazil

Nassarius levis sp. nov. e descrita para o banco de Canopus, estado do Ceara, Brasil com base na morfologia da concha. Difere das outras especies locais por apresentar uma concha mais alongada, com um escudo parietal pouco desenvolvido e uma superficie notavelmente lisa. Essa ultima caracteristica ainda nao foi descrita entre as especies de Nassarius do Atlântico oeste, mas e comum a outros congeneres do Atlântico leste, como Nassarius elatus (Gould, 1845) e Indo-Pacifico, como Nassarius excellens (Kuroda & Habe, 1961).

New records and distribution extension of Nassarius karinae Usticke, 1971 (Mollusca: Gastropoda: Nassariidae) in the SW Atlantic

We report two new records of Nassarius karinae Usticke, 1971, from Minerva Seamount and Abrolhos Archipelago, off northeastern Brazil. The new records extend the known geographic range of the species ca . 1000 km southward from Pernambuco to Bahia. These are also the first records of the species in Bahia. Additional notes on shell morphology and comparisons with other congeners are provided herein.