Aspectos ultraestruturais do espermatozóide de Natica marochiensish (Gmelin) (Mollusca, Gastropoda) do litoral norte do Brasil

Spermatozoa of Natica marochienssish (Gmelin, 1791) is described by light and electron microscopy. The spermatozoon is of the primitive type with head contains a conical acrosomal complex with an acrosomal vesicle of dense matrix having a basis occupied by the subacrosomal space. The middle piece shows the centriolar complex surrounded by mitochondria and the tail contains the axoneme with a 9+2.

Distribuição e ecomorfologia de Neritina zebra (Bruguiere, 1792) (Mollusca: Gastropoda: Neritidae), em um estuário amazônico, Pará, Brasil

O presente estudo avaliou a distribuição de Neritina zebra em um gradiente vertical em afloramentos rochosos e a distribuição entre os afloramentos de rochosos e argilitodo entremarés em um estuário na Amazônia brasileira. Os locais de coletas são caracterizados por águas oligohalinas, sendo localizadas nos distritos dede Icoaraci, Mosqueiro e município de Colares na região costeira do Estado do Pará. Para avaliar a distribuição vertical nos substratos rochosos, os moluscos foram amostrados na faixa inferior e média do mesolitoral. Na faixa inferior do mesolitoral, onde ocorrem os substratos argilito e rocha, estes foram amostrados para verificar seu efeito na distribuição entre os substratos. Em cada tipo de substrato e faixa do entremarés foram amostrados aleatoriamente 22 réplicas utilizando-se um quadrante de 25cm² na estação chuvosa e de estiagem. Análises de Variâncias foram realizadas para testar (1) o efeito da zona do entremarés e (2) o tipo de substrato na densidade de N. zebra. A análise dos resultados da distribuição vertical mostrou que a zona inferior os indivíduos juvenis apresentam maior densidade que a zona média, e um padrão oposto parece ocorrer com espécimes adultos. Quanto à distribuição nos diferentes substratos, os resultados mostraram que existem maiores densidades nos substratos rochosos que nos argilosos para os indivíduos juvenis, mas não foi encontrado um padrão para os indivíduos adultos. Esta variabilidade no padrão de densidades entre os substratos e entre as zonas do entremarés mostrou influência das estações e dos locais de coleta, apresentando Icoaraci com as menores densidades, o que pode estar associado à atividade antrópica naquela localidade.

Diversidade e distribuição do gênero Alvania (Mollusca, Gastropoda: Rissoidae) no litoral brasileiro

Os Rissoidae Gray, 1847 são compostos por conchas pequenas ou micro-conchas, abundantes nos mares de todo mundo. Uma grande diversidade das espécies desse grupo é encontrada nas zonas de maré baixa e ao longo do litoral, onde há a maior ocorrência de algas, rochas, corais e outros locais que fornecem abrigo, todavia muitos ocorrem também em zonas de mar profundo. Em Rissoidae, Alvania é um dos mais diversos quanto ao número de espécies, sendo frequentes as descrições ou re-descrições dentro desse gênero. O objetivo desse trabalho foi determinar a diversidade e a distribuição de Alvania, para assim descrever e ampliar o conhecimento sobre a fauna no litoral brasileiro, através das análises conquiológicas, além da distribuição geográfica e batimétrica das espécies desse gênero. Todo o material é proveniente de coleções de museus, campanhas oceanográficas e também de material coletado no segundo semestre de 2010 e em 2011. Anteriormente, foram listadas 7 espécies para a costa oeste do Atlântico, sendo que no presente trabalho três dessas espécies não foram encontradas. Foram analisados 3599 indivíduos pertencentes a dez espécies: Alvania auberiana (Orbigny, 1842); Alvania cancapae Bouchet & Warén, 1993; Alvania colombiana Rommer & Moore, 1988; Alvania faberi De Jong & Coomans, 1988; Alvania tarsodes (Watson, 1886), Alvania valeriae Absalão, 1993, além de quatro possíveis novas espécies: Alvania sp. nov. 1, Alvania sp. nov. 2, Alvania sp. nov. 3, Alvania sp. nov.4.

The first fossil avian egg from Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The puzzle assembled: Ediacaran guide fossil Cloudina reveals an old proto-Gondwana seaway

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Heydrichia (?) poignantii, sp nov (Sporolithaceae, Sporolithales, Rhodophyta), a 100 million year old fossil coralline red alga from north-eastern Brazil, and a new Hauterivian record of Sporolithon from Switzerland

Fossil specimens of Heydrichia (?) poignantii, sp. nov. (Sporolithaceae, Sporolithales, Rhodophyta), representing the first confirmation of the genus in the fossil record, were discovered in thin sections of Albian limestones from the Riachuelo Formation, Sergipe Basin, and in thin sections of Albian -Cenomanian limestones from the Ponta do Mel Formation, Potiguar Basin in north-eastern Brazil. A detailed morphological-anatomical account of the species is provided, and its placement in Heydrichia is discussed in relation to current classification proposals. Comparisons with the four other known species of the genus, all non-fossil, show that H. poignantii is the only known species of Heydrichia in which thalli are encrusting to sparsely warty to horizontally layered with overlapping lamellate branches that commonly appear variously curved or arched, and in which thalli have sporangial complexes that become buried in the thallus. The evolutionary history of Heydrichia remains uncertain, but available data suggest that the genus may have diverged from the sporolithacean genus Sporolithon, known as early as Hauterivian times (c. 129.4-132.9 +/- 1 Ma) from Spain (and newly reported here from Switzerland), or it may have arisen from a graticulacean alga such as Graticula, dating from mid-Silurian times (c. 427-435 Ma). Current data also suggest that Heydrichia is more likely to have arrived in Brazil from Central Atlantic waters than from higher latitude South Atlantic waters. This implies that currently living species in southern Africa probably arose later from ancestors further equatorward in the South Atlantic, although confirming studies are needed. All non-fossil species of Heydrichia are known only from the southern hemisphere.

Correlation Between Apparent Activation Energy and NOx emission of renewable diesel from sugar cane, biodiesel, fossil diesel and their blends

Biofuels and their blends with fossil fuel are important energy resources, which production and application have been largely increased internationally. This study focus on the development of a correlation between apparent activation energy (Ea) and NOx emission of the thermal decomposition of three pure fuels: farnasane (renewable diesel from sugar cane), biodiesel and fossil diesel and their blends. Apparent Activation energy was determined by using thermogravimetry and Model-Free Kinetics. NOx emission was obtained from the European Stationary Cycle (ESC) with OM 926LA CONAMA P7/Euro 5 engine. Results showed that there is a linear correlation between apparent activation energy and NOx emission with R2 of 0,9667 considering pure fuels and their blends which is given as: NOx = 2,2514Ea - 96,309. The average absolute error of this correlation is 2.96% with respect to the measured NOx value. The main advantage of this correlation is its capability to predict NOx emission when either a new pure fuel or a blend of fuels is proposed to use in enginees.

Ocorrência de Angiostrongylus cantonensis (Nematoda, Angiostrongylidae) em Achatina fulica (Mollusca, Gastropoda) na Baixada Santista

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Mesodictyon, A New Fossil Genus of the Centric Diatom Family Thalassiosiraceae from the Miocene Chalk Hills Formation, Western Snake River Plain, Idaho

Three new centric diatom species assigned to a new genus are described from Miocene lacustrine deposits of Idaho. Species of the new genus, Mesodictyon, have the areola cribrum in the middle of the loculus, strutted processes and radiating, non-fasciculated striae. The strutted processes of M. magnum (diameter 60-150 μm) have long (2-3 μm) tubular extensions. The strutted processes of M. fovis (diameter 14-80 μm) are in distinct pits near the junction of the face and mantle. The valve face of M. undulatum (diameter 10-44 μm) is weakly tangentially undulate. Preliminary evidence indicates that Mesodictyon has a wide geographic distribution and may be a useful biostratigraphic marker.

Allometric growth of a common Nassariidae (Gastropoda) in south-east Brazil

The allometric growth of two groups of Nassarius vibex on beds of the bivalve Mytella charruana on the northern coast of the State of Sao Paulo, was evaluated between September 2006 and February 2007 in the bed on Camaroeiro Beach, and from March 2007 to June 2007 at Cidade Beach. The shells from Camaroeiro were longer and wider and had a smaller shell aperture than those from Cidade; a principal components analysis also confirmed different morphometric patterns between the areas. The allometric growth of the two groups showed great variation in the development of individuals. The increase of shell width and height in relation to shell length did not differ between the two areas. Shell aperture showed a contrasting growth pattern, with individuals from Camaroeiro having smaller apertures. The methodology based on Kullback-Leibler information theory and the multi-model inference showed, for N. vibex, that the classic linear allometric growth was not the most suitable explanation for the observed morphometric relationships. The patterns of relative growth observed in the two groups of N. vibex may be a consequence of different growth and variation rates, which modifies the development of the individuals. Other factors such as food resource availability and environmental parameters, which might also differ between the two areas, should also be considered.

Temporal variation in egg-capsule deposition by Nassarius vibex (Gastropoda: Nassariidae)

The morphology and the deposition periods of egg capsules by the bruised nassa Nassarius vibex were investigated on two beaches located on the southeast coast of Brazil. The nassariids were associated with the charru mussel Mytella charruana, which forms beds on soft mud-bottoms. A total of 1558 capsules were collected, only from the fronds of the green alga Ulva lactuca, 859 for Camaroeiro Beach and 699 for Cidade Beach. The mean sizes of the egg capsules and numbers of eggs or larvae per capsule were similar on the two beaches, as were the periods of capsule deposition. At Camaroeiro Beach, capsules first appeared in May 2006, reached a peak in August 2006, and disappeared in December 2006. At Cidade Beach, the first capsules were recorded in July 2006, with a peak in August 2006. A second peak was also observed at this beach between January 2007 and April 2007. The two periods of deposition recorded at the latter beach may indicate two periods of recruitment in the same year for N. vibex. Regarding the influence of intertidal level on capsule deposition, there was a significant difference in the number of capsules between the levels at Camaroeiro Beach (F= 7.445, p<0.05), and for the second capsule-deposition peak at Cidade Beach (F= 6.382, p<0.05). This study revealed a selective pattern of capsule deposition, with individuals of N. vibex using only fronds of U. lactuca. This process was influenced by the morphodynamics of the two beaches, with the nassariids maximizing the survival of embryos by depositing more capsules and more eggs per capsule in better-protected parts of the mytilid beds.

Extremely slow feeding in a tropical drilling ectoparasite, Vitularia salebrosa (King and Broderip, 1832) (Gastropoda: Muricidae), on molluscan hosts from Pacific Panama

This study documents one of the slowest feeding behaviors ever recorded for a muricid gastropod in one of the most biotically rigorous regions on the planet. In Pacific Panama, Vitularia salebrosa attacks mollusks by drilling through their shells. The duration of attacks estimated by isotope sclerochronology of oyster shells collected during attacks in progress range from 90 to 230 days, while experimental observation of interactions documented one attack greater than 103 days. The prolonged nature of attacks suggests that V. salebrosa is best characterized as an ectoparasite than as a predator, which is the ancestral condition in the Muricidae. An ectoparasitic lifestyle is also evident in the unusual interaction traces of this species, which include foot scars, feeding tunnels and feeding tubes, specialized soft anatomy, and in the formation of male-female Pairs, which is consistent with protandrous hermaphroditism, as is typical in sedentary gastropods. To delay death of its host, V. salebrosa targets renewable resources when feeding, such as blood and digestive glands. A congener, Vitularia miliaris from the Indo-Pacific, has an identical feeding biology The origin and persistence of extremely slow feeding in the tropics challenges our present understanding of selective pressures influencing the evolution of muricid feeding behaviors and morphological adaptations. Previously, it has been suggested that faster feeding is advantageous because it permits predators to spend a greater proportion of time hiding in enemy-free refugia or to take additional prey, the energetic benefits of which could be translated into increased fecundity or defenses. The benefits of exceptionally slow feeding have received little consideration. In the microhabitat preferred by V. salebrosa (beneath boulders), it is possible that prolonged interactions with hosts decrease vulnerability to enemies by reducing the frequency of risky foraging events between feedings . Ectoparasitic feeding through tunnels by V. salebrosa may also reduce competitive interactions with kleptoparasites (e.g., crabs, snails) that steal food through the gaped valves of dead or dying hosts.

Description of a new species of Calliostoma (Gastropoda, Calliostomatidae) from Southeastern Brazil

Calliostoma tupinamba is a new species from Southeastern Brazil, ranging from southern Rio de Janeiro to northern Sao Paulo, and found only on coastal islands, on rocks and sessile invertebrates at 3 to 5 meters of depth. Shell and soft part morphology is described here in detail. Calliostoma tupinamba is mainly characterized by a depressed trochoid shell; eight slightly convex whorls; a sharply suprasutural carina starting on the third whorl and forming a peripheral rounded keel; and a whitish, funnel-shaped and deep umbilicus, measuring about 5%-10% of maximum shell width. Calliostoma tupinamba resembles C. bullisi Clench & Turner, 1960 in shape, but differs from it in being taller and wider, having a smaller umbilicus and lacking a strong and large innermost spiral cord at its base. Finally, an identification key of Brazilian Calliostoma species is presented.

Morphology and biological aspects of Gundlachia ticaga from SE Brazil (Gastropoda: Basommatophora: Ancylidae)

Some aspects of the biology, reproduction and morphology of Gundlachia ticaga (MARCUS & MARCUS 1962) were studied and compared with literature data. A sample of similar to 100 specimens, collected in a darn in Ribeirao Preto, were maintained in Petri dishes at the laboratory during a period no longer than a month. The oviposition, number of capsules, and incubation time of eggs were registered for each individual. A morphologic study was carried out in both, alive and fixed specimens. Although some morphological discrepancies were identified, the majority of data confirms what was previously described for the species. Regarding the biology, however, the results were somewhat different from those previously reported. The incubation time of the eggs varied from 10 to 13 days, and the number of embryos in the interior of the ovigerous capsules varied from 1 to 4. In addition, each individual laid 9 eggs during the first month of the reproductive period. The formation of septa occurred in some animals and intermediary phases are figured.

Taxonomic study on the molluscs collected in Marion-Dufresne expedition (MD55) to SE Brazil: Xenophoridae, Cypraeoidea, mitriforms and Terebridae (Caenogastropoda)

The deep-water molluscs collected during the expedition MD55 off SE Brazil have been gradually studied in some previous papers. The present one is focused on samples belonging to caenogastropod taxa Xenophoridae Troschel, 1852, Cypraeoidea Rafinesque, 1815, mitriforms and Terebridae Morch, 1852. Regarding the Xenophoridae, Onustus aquitanus n. sp. is a new species, collected off the littoral of Espirito Santo and Rio de Janeiro, Brazil, 430-637 m depth (continental slope). The main characters of the species include the small size (c. 20 mm), the proportionally wide shell, the white colour, the short peripheral flange, the oblique riblets weakly developed and a brown multispiral protoconch. This appears to be the smallest living species of the family, resembling in this aspect fossil species. In respect to the Cypraeoidea, the following results were obtained: family Cypraeidae Rafinesque, 1815: Erosaria acicularis (Gmelin, 1791) and Luria cinerea (Gmelin, 1791) had the deepest record, respectively 607-620 m and 295-940 m, although the samples were all dead, eroded shells. Family Lamellariidae d'Orbigny, 1841: a total of three lots were collected, provisionally identified as Lamellaria spp. as the samples consist of only vestigial shells; possibly each lot represents a different species. Family Pediculariidae Gray, 1853: a sample of Pedicularia tibia Simone, 2005 was found, expanding the range c. 1000 km southwards, from Ceara to Espirito Santo. Family Ovulidae Fleming, 1822: Pseudosimnia lacrima n. sp., collected off Espirito Santo, 607-620 m depth, is described here and is mainly characterised by its strong biconic outline, small size (c. 7 mm), and a thick peripheral callus. Family Triviidae Troschel, 1863: Cleotrivia antillarum (Schilder, 1922) is recorded for the first time as deep as 620 m, and its distribution expanded from Rio Grande do Norte to Espirito Santo; Dolichupis akangus n. sp. with rounded outline and c. 15 transverse ribs; D. pingius n. sp. with the outer lip expanded posteriorly and c. 10 ribs. In respect to the mitriform neogastropods, the following species are emphasised: family Costellariidae MacDonald, 1860: Vexillum sp., 607-620 m depth; Turricostellaria amphissa n. sp., 295 m depth; T. jukyry n. sp.; T. apyrahi n. sp., both 790-1575 m depth; T. ovir n. sp., 1200 m depth; Nodicostellaria crassa (Simone, 1995), 240-600 m depth, with extension northwards of the range up to Espirito Santo; Austromitra decresca n. sp., 60-105 m depth. Family Mitridae Swainson, 1829: Subcancilla joapyra n. sp., 295 m depth; S. cf. straminea (Adams, 1853), 607-620 m depth. Family Volutomitridae Gray, 1854: Microvoluta corona n. sp., 1500-1575 m depth. Family Mitromorphidae Casey, 1904: Mitromorpha sama n. sp., 607-940 m depth; M. mirim n. sp., 60105 m depth. Regarding the conoidean Terebridae, this paper is a complement of a previous study. It deals with a new species Terebra assu Simone n. sp., from the Abrolhos Bank, 295 m depth, characterised by its narrow outline, yellowish colour, weak sculpture on the last whorls, and a proportionally broad, paucispiral protoconch. A second finding of Terebra alagoensis Lima, Tenorio & Barros, 2007 expands the geographic range from Alagoas to north Espirito Santo. A discussion on the systematics of the "complex Terebra doellojuradoi" in South American coast is also provided, highlighting the improbability of synonymy between T. leptapsis Simone, 1999 and T doellojuradoi Carcelles, 1953. Differences in size, sculpture, spire angulation, aperture, and mainly in protoconch, indicate specific separations. The presently studied terebrids belong to the "complex Terebra doellojuradoi", which encompasses closely related, deep-water, small species, possessing a relatively high degree of endemicity.