Resumen (Objetivo). Se evaluó el manglar de Chacarita en el Pacífico Central de Costa Rica, a través de la composición florística y las poblaciones de moluscos asociados de interés comercial, con el fin de proponer actividades de aprovechamiento sustentables en el manglar. (Metodología). Mensualmente y durante un año, se realizaron visitas al área de estudio, con el propósito de establecer una base florística de árboles de mangle y medir el almacenamiento de carbono en el lugar, además, de recolectar moluscos bivalvos para analizar el estado de las poblaciones, con base en las abundancias de organismos hallados y otras características como las longitudes y la masa de estos. En los mangles, se obtuvo el diámetro de la altura de pecho (DAP en cm), la altura (m), el índice de valor de importancia (IVI) y las reservas de carbono (Mg C·ha-1). En cuanto a los moluscos, se examinaron cuatro especies de interés comercial, evaluando la longitud (cm), la masa (g) y el índice gonadosomático. Finalmente, se realizaron valoraciones económicas de los datos obtenidos en el manglar, del turismo e información histórica de pesca para el acopio de Chacarita. (Resultados). Se hallaron cinco especies de mangles, Rhizophora mangle, Rizophora racemosa, Laguncularia racemosa, Avicennia germinans y Pelliciera rhizophorae; P. rhizophorae fue la de mayor índice de valor de importancia. Se obtuvo un almacenamiento de carbono equivalente a 78.49 Mg C·ha-1. Se contabilizaron 357 organismos, de los cuales el 18 % correspondió a Anadara similis, 37.5 % a Anadara tuberculosa, 41.46 % a Leukoma spp. y 3.08 % a Mytella guyanensis. Tomando en cuenta el valor económico de las reservas de carbono y los moluscos bivalvos presentes en los muestreos, se obtuvieron valoraciones económicas de 9812.63 USD·ha-1 y 28 USD·ha-1, respectivamente. (Conclusiones). Las bajas densidades poblacionales de moluscos, especialmente del género Anadara, hacen necesario establecer medidas de gestión que permitan recuperar las poblaciones de estos. La presente investigación propone actividades de aprovechamiento sustentables, como turismo comunitario con fines educativos y culturales.

Resumo (Objetivo). O mangue de Chacarita, no Pacífico Central da Costa Rica, foi avaliado por meio da composição florística e das populações de moluscos associados de interesse comercial, com o objetivo de propor atividades de uso sustentável no mangue. (Metodologia). Foram feitas visitas mensais à área de estudo durante um ano para estabelecer uma base florística de árvores do mangue e medir o armazenamento de carbono no local, bem como para coletar moluscos bivalves para analisar o status das populações, com base na abundância de organismos encontrados e em outras características, como comprimento e massa de tais organismos. Nos manguezais, foram obtidos o diâmetro à altura do peito (DAP em cm), a altura (m), o índice de valor de importância (IVI) e as reservas de carbono (Mg C-ha-1). No que diz respeito aos moluscos, foram examinadas quatro espécies de interesse comercial., avaliando o comprimento (cm), a massa (g) e o índice gonadossomático. Por fim, foram feitas avaliações econômicas de dados de mangue, turismo e informações históricas de pesca para a coleção Chacarita. (Resultados). Foram encontradas cinco espécies de mangue, Rhizophora mangle, Rizophora racemosa, Laguncularia racemosa, Avicennia germinans e Pelliciera rhizophorae; a P. rhizophorae apresentou o índice de valor de importância mais alto. Foi obtido um armazenamento de carbono equivalente a 78.49 Mg C-ha-1. Foram calculados um total de 357 organismos, dos quais 18% correspondeu a Anadara similis, 37.5% Anadara tuberculosa, 41.46% Leukoma spp. e 3.08% Mytella guyanensis. Levando em conta o valor econômico das reservas de carbono e dos moluscos bivalves presentes nas amostras, foram obtidas avaliações econômicas de US$ 9812.63 ha-1 e US$ 28 ha-1, respectivamente. (Conclusões). As baixas densidades populacionais de moluscos, especialmente do gênero Anadara tornam necessário o estabelecimento de medidas de manejo para permitir a recuperação dessas populações. Esta pesquisa propõe atividades de uso sustentável, como o turismo comunitário para fins educacionais e culturais.

Abstract (Objective). The floristic composition and populations of associated molluscs of commercial interest of the Chacarita mangrove forest on the Central Pacific of Costa Rica were evaluated to guide proposals for sustainable exploitation activities in the mangrove forest. (Methodology). Monthly visits to the study area were conducted for one year to establish a floristic baseline of mangrove trees and measure carbon storage. Additionally, bivalve molluscs were collected to analyze the state of their populations based on the abundances of organisms found, as well as other characteristics such as length and mass. Data regarding the mangrove trees included their diameter at breast height (DBH, cm), height (m), importance value index (IVI), and carbon reserves (Mg C·ha-1). Four mollusc species of commercial interest were analyzed, using data on their length (cm), weight (g), and gonodosomatic index. Economic evaluations were also conducted using data obtained from the mangrove forest, as well as tourism and historical fishing data for the collection of Chacarita. (Results). Five species of mangroves were identified: Rhizophora mangle, Rizophora racemosa, Laguncularia racemosa, Avice germinans, and Pelliciera rhizophorae, while P. rhizophorae had the highest importance value index. The study revealed a carbon storage equivalent to 78.49 Mg C·ha-1. A total of 357 organisms were counted, with Anadara similis accounting for 18% of the total count, followed by Anadara tuberculosa (37.5%), Leukoma spp. (41.46%), and Mytella guyanensis (3.08%). When considering the economic value of carbon stocks and the bivalve molluscs obtained from the samples, economic valuations of 9,812.63 USD·ha-1 and 28 USD·ha-1 were determined, respectively. (Conclusions). The low population densities of molluscs, particularly those belonging to the Anadara genus, necessitate the establishment of management measures to facilitate the recovery of these mollusk populations. This research proposes sustainable use activities such as community tourism for educational and cultural purposes.

ABSTRACT Harmful algal blooms (HABs) can negatively affect coastal water quality, aquatic fauna, and human health from the consumption of toxin-contaminated seafood. Estuaries are especially prone to the incidence of these noxious events and sensitive to the associated damage. This study represents a comprehensive overview of previous investigations reporting the occurrence of harmful algae and/or phycotoxins in the Paranaguá Estuarine Complex (CEP), in Southern Brazil. Secondary data from 2002 to 2021 were combined with new results obtained from widely spaced sampling campaigns performed from 2018 to 2019 to assess the periods and estuarine sectors at greater risk for the incidence of HABs. In total, about 600 water/sediment samples containing harmful microalgae and 675 tissue samples of phycotoxin-contaminated fauna were analyzed. The most frequent and abundant species of potentially toxic microalgae were dinoflagellates belonging to the species complexes Dinophysis acuminata and Prorocentrum lima, producers of diarrhetic shellfish toxins (DSTs), and diatoms of the genus Pseudo-nitzschia, producers of amnesic shellfish toxins (ASTs). Okadaic acid, a DST, was by far the most common toxin in the fauna, reaching higher levels in primary consumers such as bivalve mollusks (mussels, oysters, and clams), zooplankton, and suspension-feeding crustaceans (ghost shrimps), and moderate to low levels in cephalopods, fishes, gastropods, echinoderms, sea turtles, seabirds, and cetaceans. Less rainy periods (winter-early spring) were associated with the highest incidence of DSTs and blooms of their producing algae P. lima and Dinophysis spp., mainly in the middle region of Paranaguá Bay and on the shallow continental platform adjacent to the estuarine mouth. However, certain HAB-forming species may be more successful in inner estuarine areas ( Prorocentrum cordatum) and during different periods, such as late summer—early fall ( Pseudo-nitzschia spp.). Continuous monitoring of harmful algae and toxins is therefore highly recommended to mitigate the effects of HABs in the entire estuary. (HABs quality toxincontaminated contaminated seafood damage andor or CEP, CEP , (CEP) Brazil 200 202 201 total 60 watersediment sediment 67 phycotoxincontaminated phycotoxin analyzed DSTs, (DSTs) Pseudonitzschia, Pseudonitzschia Pseudo nitzschia, nitzschia ASTs. ASTs . (ASTs) acid DST mussels, mussels (mussels oysters clams, clams clams) zooplankton suspensionfeeding suspension feeding ghost shrimps, shrimps shrimps) cephalopods fishes gastropods echinoderms turtles seabirds cetaceans winterearly winter early spring P spp spp. mouth However HABforming HAB forming cordatum summerearly summer spp.. spp.) estuary (CEP 20 6 (DSTs (ASTs 2

Resumo Estuários recebem entradas diárias de elementos químicos, que podem impactar a qualidade de água e do sedimento, assim como a saúde da biota. Além do sedimento, moluscos bivalves têm sido utilizados no monitoramento químico desses sistemas. Neste estudo investigou-se a presença e os teores de As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb e Zn no sedimento superficial e em bivalves (Crassostrea gasar, C. rhizophorae e Mytella guyanensis) de estuários do sul / extremo sul do estado da Bahia, Nordeste do Brasil. As amostras foram avaliadas por espectrometria de emissão óptica de plasma indutivamente acoplado (ICP-OES, Varian 710). Exceto Cd, todos os demais elementos foram encontrados nas amostras, sendo que Co foi exclusivo no sedimento. Os estuários equivalentes às estações amostrais #1 - Valença, #2 - Taperoá, #3 - Ilhéus e #4 - Belmonte mostraram níveis de metais compatíveis com os estabelecidos pela legislação brasileira, porém, a #5 - Santa Cruz Cabrália, além da presença de As, apresentou alto nível de Pb e de Cu em C. gasar, o que foi atribuído aos impactos por atividades náuticas nesse local.

Abstract Estuaries receive daily inputs of chemical elements which can impact the quality of water and sediment, as well as the health of biota. In addition to the sediment, bivalve mollusks have been used in the chemical monitoring of these systems. This study investigated the presence and contents of As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn in superficial sediment and in bivalves (Crassostrea gasar, C. rhizophorae and Mytella guyanensis) from estuaries in the south / extreme south of Bahia State, northeast Brazil. The samples were evaluated with inductively coupled plasma optical emission spectrometry (ICP-OES, Varian 710). Except for Cd, all other elements were found in the samples, being that Co was exclusive in the sediment. The estuaries equivalent to sampling stations #1 - Valença, #2 - Taperoá, #3 - Ilhéus and #4 - Belmonte showed levels of metals compatibles with those established by the Brazilian legislation, however, the #5 - Santa Cruz Cabrália, in addition to the presence of As, presented a high level of Pb and Cu in C. gasar, which was attributed to the impacts of nautical activities in that locality.

ABSTRACT Background: After its transfaunation from the Atlantic Ocean has been reported, the protozoan Perkinsus marinus has expanded its list of hosts in several species of mollusks in the Pacific Ocean, both in cultivation and in wild populations. Goals: The presence of this parasite was evaluated in the horsemussel Modiolus capax, in the southwestern Gulf of California. Methods: 60 mussels were collected per annual season for one year (summer, autumn, winter 2019-spring 2020, N = 240), in the mining port of Santa Rosalía (SR), Baja California Sur, Mexico. Thioglycollate staining was used to detect presumptive hypnospores and the polymerase chain reaction (PCR) technique for its confirmation. The prevalence, parasite load and intensity of infection were obtained in each sampling. Results: Presumptive hypnospores of the parasite were detected with thioglycollate staining in almost 20% of the samples analyzed, of which only 5% were positive for confirmation with PCR. Neither the prevalence (6.66-33.33%) nor the parasite load (˂ 2.75 hypnospores/g) showed a tendency to increase with time; the intensity of infection ranged from negative to light. Salinity showed correlation with parasite load (r = 0.99, p = 0.002). Conclusions: The results suggest that M. capax in SR presented low susceptibility to the parasite, so its health is not compromised when hosting P. marinus. Although it is the first report of the protozoan in this mussel, continuous monitoring is recommended to know not only the health status of the bivalve in the region, but also of the other species of mollusks that inhabit there.

RESUMEN Antecedentes: Después de haberse reportado su transfaunación del océano Atlántico, el protozoario Perkinsus marinus ha ampliado su listado de hospederos en varias especies de moluscos del océano Pacífico, tanto en cultivo como de poblaciones silvestres. Objetivos: Se evaluó la presencia de este parásito en el mejillón “choro”, Modiolus capax, en el suroeste del Golfo de California. Métodos: Se colectaron 60 mejillones por estación anual durante un año (verano, otoño, invierno 2019-primavera 2020, n = 240), en el puerto minero de Santa Rosalía (SR), Baja California Sur, México. Se utilizó la tinción con tioglicolato para detectar presuntas hipnosporas y la técnica de reacción en cadena de la polimerasa (PCR) para su confirmación. Se obtuvieron la prevalencia, carga parasitaria e intensidad de infección en cada muestreo. Resultado: Se detectaron presuntas hipnosporas del parásito con la tinción de tioglicolato, en casi 20% de las muestras analizadas, de las que sólo el 5% fueron positivas para su confirmación con PCR. Ni la prevalencia (6.66-33.33%) ni la carga parasitaria (˂ 2.75 hipnosporas/g) mostraron una tendencia a aumentar con el tiempo; la intensidad de infección fue de negativa a ligera. La salinidad mostró correlación con la carga parasitaria (r = 0.99, p = 0.002). Conclusiones: Los resultados sugieren que M. capax en SR presentó baja susceptibilidad al parásito, por lo que su salud no se encuentra comprometida al hospedar a P. marinus. Aunque es el primer reporte del protozoario en este mejillón, es recomendable el monitoreo continuo para conocer, no solo el estado sanitario del bivalvo en la región, sino también, de las otras especies de moluscos que ahí habitan.

Abstract: The objectives of this research were to estimate the abundance of the main groups of planktonic mollusks (meroplanktonic larvae, holoplanktonic gastropods and cephalopod paralarvae), and relate these groups to the physical-chemical water properties along a longitudinal gradient between Caldera, on the coast of mainland Chile and the Easter Island ecoregion (Rapa Nui Island and Salas y Gómez Island), in the Southeast Pacific Ocean. Plankton samples were collected over the course of the CIMAR 21-Islas Cruise, from October to November 2015, at 33 oceanographic stations via vertical hauls of a WP2 net (180-µm mesh size) from a maximum depth of 300 m to the sea surface. Mollusks were sorted, counted and initially assigned to Class rank, later being identified to lower taxonomic ranks. Planktonic mollusks were obtained at all stations, and were composed of 92.7% of Gastropoda and 7.3% of Bivalvia. The total abundance of mollusks varied between 55 and 4,922 individuals 100 m-3. Euthecosomate gastropods exhibited the highest occurrence within the oceanic area. Meanwhile, no paralarvae were captured. Differences in the composition of planktonic mollusks between the continental and oceanic zones were evident. Bivalve larvae increased their abundance in warmer, salty and vertically mixed waters. These results are the first record of meroplanktonic mollusks in waters near the Chilean oceanic islands, and suggest that planktonic mollusks display spatial variation at the scale of the South Pacific Basin, which could be related to the hydrographic conditions and the water column structure.

Resumen: Los objetivos de esta investigación fueron estimar la abundancia de los principales grupos de moluscos planctónicos (larvas meroplanctónicas, gasterópodos holoplanctónicos y paralarvas de cefalópodos) y relacionarla con las propiedades fisicoquímicas del agua, a lo largo de un gradiente longitudinal entre Caldera en la costa continental de Chile la ecorregión de Isla de Pascua (Isla de Rapa Nui e Isla Salas y Gómez), en el sureste del océano Pacífico. Se recolectaron muestras de plancton durante el Crucero CIMAR 21-Islas, en octubre y noviembre de 2015, en 33 estaciones oceanográficas con una red WP2 (180 µm de abertura de malla) en lances verticales entre los 300 m de profundidad y la superficie del mar. Los moluscos se clasificaron, contaron y asignaron inicialmente a nivel de Clase, para su posterior identificación en niveles taxonómicos inferiores. Se obtuvieron moluscos planctónicos en todas las estaciones, con 92,7% de Gastropoda y 7,3% de Bivalvia. La abundancia total de moluscos varió entre 55 y 4.922 individuos 100 m-3. Los gasterópodos Euthecosomata exhibieron la mayor ocurrencia en el área oceánica. No se obtuvieron paralarvas. Las diferencias en la composición de los moluscos planctónicos entre las zonas continental y oceánica se hicieron evidentes. Las larvas de bivalvos aumentaron su abundancia en aguas más cálidas, saladas y verticalmente mezcladas. Estos resultados son el primer registro de moluscos meroplanctónicos en aguas cercanas a las islas oceánicas chilenas. Los moluscos planctónicos presentan una variación espacial a escala de la cuenca del Pacífico Sur, relacionada con las condiciones hidrográficas y la estructura de la columna de agua.

ABSTRACT Individuals of mussels were collected in ponds from a commercial shrimp farm in the Unare region, Anzoátegui State, Venezuela. Identification was carried out using dichotomous keys and corroborated via analysis of similarities between the sequences of partial mitochondrial DNA of the cytochrome oxidase gene and Mytella strigata (Hanley, 1843) reported in GenBank with 99-100% similarity. Morphological analyses further supported the identification of the specimen. The first report of M. strigata in the Venezuelan Caribbean coast suggests that it could be a transplanted species. Possible negative effects of M. strigata on commercial shrimp production systems are discussed.

Resumo O objetivo deste estudo foi detectar DNA de Toxoplasma gondii em ostras (Crassostrea spp.) comercializadas em sete praias do Estado do Pará, Brasil. De acordo com o Programa Nacional de Controle Higiênico Sanitário de Moluscos Bivalves, 100 g da parte comestível dos moluscos são necessários para a análise de microrganismos contaminantes. Neste estudo, 12 ostras foram consideradas equivalentes a 100 g de partes comestíveis na preparação de cada amostra agrupada. No total, 360 ostras foram compradas de 30 vendedores. De grupos de 12 ostras adquiridas por vendedor, foram obtidas 60 amostras agrupadas, compreendendo 30 tecidos branquiais e 30 tratos gastrointestinais. Para a análise molecular, a nested PCR foi realizada para amplificar um produto de 155 pares de bases do gene B1 de T. gondii. Todas as amostras analisadas foram negativas para T. gondii. Os resultados indicam que as amostras de ostras comercializadas em praias do Estado do Pará não foram contaminadas por T. gondii.

Abstract The aim of this study was to detect Toxoplasma gondii DNA in oysters (Crassostrea spp.) sold on seven beaches in the State of Pará, Brazil. According to the National Program for Hygiene and Sanitary Control of Bivalve Mollusks, 100 g of the edible part of mollusks is required to analyze contaminating microorganisms. In this study, 12 oysters were assumed to be equivalent to 100 g of edible parts when preparing each pooled sample. In total, 360 oysters were purchased from 30 vendors. From groups of 12 oysters purchased per vendor, 60 pooled samples were obtained, comprising 30 gill tissues and 30 gastrointestinal tracts. For molecular analysis, nested-PCR was conducted to amplify a 155-base-pair product of the B1 gene from T. gondii. All analyzed samples were negative for T. gondii. Our findings indicate that the oyster samples sold on the beaches in the State of Pará were not contaminated by T. gondii.

Resumo O Brasil tem vivenciado um aumento no uso de agroquímicos nos últimos anos, representando uma ameaça potencial aos ecossistemas. O reservatório de Volta Grande (Minas Gerais/São Paulo, Brasil) tem cerca de 87% de sua área cercada por sistemas agrícolas, e muitos compostos usados na agricultura acabam sendo transportados para corpos d'água próximos. Dado o potencial risco ecológico, nosso objetivo foi avaliar a presença de pesticidas utilizando moluscos de água doce como bioindicadores no reservatório de Volta Grande. Coletamos espécimes de dois bivalves e três gastrópodes usando dragas de fundo e sondagem visual, em três locais diferentes dentro do reservatório. Todos os pontos de amostragem foram classificados de acordo com suas distâncias da barragem, e todos estavam próximos a terras agrícolas. As amostras foram processadas e congeladas para análise toxicológica qualitativa por espectrofotometria de massa. Oito pesticidas foram identificados, incluindo quatro organoclorados (Aldrin, p,p’-DDE, Heptacloro epóxido e Endrin) e organofosforados (Disulfato, Malation, Paration-metil e Paration-etil). Todas as cinco espécies estudadas (Limnoperna fortunei, Corbicula fluminea, Melanoides tuberculata, Aylacostoma tenuilabris e Pomacea aff. canaliculata) apresentaram vestígios de pesticidas nos tecidos. Dos oito agrotóxicos encontrados em nossa análise, seis são ilegais no Brasil, reforçando a preocupação sobre o uso contínuo de agrotóxicos proibidos e também o risco ecológico na área do reservatório de Volta Grande. De acordo com os nossos resultados sugere-se um controle ambiental mais rigoroso por parte dos órgãos ambientais em relação ao uso e comercialização desses compostos tóxicos ilegais.

Abstract Brazil has experienced a rise in the use of agrochemicals in recent years, representing a potential threat to nearby ecosystems. The Volta Grande Reservoir (Minas Gerais/São Paulo, Brazil) has about 87% of its area surrounded by agricultural systems, and many compounds used in agriculture end up being carried into nearby water bodies. Given the potential ecological risk, our purpose was to assess pesticides in the reservoir. We collected specimens of two bivalves and three gastropods using bottom dredging and visual investigation in three different sites within the reservoir. The sampling sites were classified according to their distance from the dam, and all were close to agricultural lands. The samples were processed and frozen for qualitative toxicological analysis using mass spectrophotometry. Eight pesticides were identified, including four organochlorines (Aldrin, p,p’-DDE, Heptachlor epoxide, and Endrin) and organophosphates (Disulfoton, Malathion, Parathion- methyl, and Parathion-ethyl). All five studied species (Limnoperna fortunei, Corbicula fluminea, Melanoides tuberculata, Aylacostoma tenuilabris, and Pomacea aff. canaliculata) presented traces of pesticides in their bodies. Of the eight pesticides found in our analysis, six are illegal in Brazil, raising awareness about the continuous use of forbidden pesticides, and also the ecological risk in the Volta Grande Reservoir area. Our results suggest stricter control by environmental agencies regarding the use and commercialization of these illegal toxic compounds.

Abstract We report the mollusks associated to the right valve of the rock oyster Striostrea prismatica Gray, 1825. A total of twelve valves preserved in 96 % alcohol were examined. The mollusks associated to the valves were examined using a stereoscope. The valves analysed had a minimum length of 61.1 mm and a maximum length of 84.2 mm. A total of 164 molluscs associated to the twelve valves were quantified, represented by the classes Gastropoda and Bivalvia, with a total of 8 families, 11 genera, and 12 species. We identified four species of gastropods and eight species of bivalves. The most abundant families were Mytilidae (Bivalvia) with 64.0 % and Hipponicidae (Gastropoda) with 11.6 %. The average abundance of the study was 13.7 molluscs/valve. Internal marks were quantified in the valves, caused by the borer bivalve Leiosolenus aristatus. This study contributes to the diversity of mollusks associated to Striostrea prismatica.

Resumen Reportamos los moluscos asociados a la valva derecha del ostión de roca Striostrea prismatica Gray, 1825. Un total de doce valvas preservadas en alcohol al 96 % fueron examinadas. Los moluscos asociados a las valvas fueron examinados con ayuda de un estereoscopio. Las valvas analizadas tuvieron una longitud mínima de 61.1 mm y máxima de 84.2 mm. Se cuantificaron un total de 164 moluscos asociados a las doce valvas, representados por las clases Gastropoda y Bivalvia, con un total de 8 familias, 11 géneros, y 12 especies. Los gasterópodos estuvieron representados por 4 especies y los bivalvos por 8 especies. Las familias más abundantes fueron Mytilidae (Bivalvia) con 64.0 % e Hipponicidae (Gastropoda) con 11.6 %. La abundancia promedio del estudio fue 13.7 moluscos/valva. Se cuantificaron marcas internas en las valvas, ocasionadas por el bivalvo perforador Leiosolenus aristatus. Este es el primer estudio que contribuye a la diversidad de moluscos asociados a Striostrea prismatica.

ABSTRACT Background: Marine gastropods and bivalves are some of the most diverse invertebrate groups in nature, but in Mexico a better knowledge of their taxonomic composition is required. Although there are important studies on mollusks in the Mexican Caribbean, some areas such as island of Cozumel have been barely studied. Goals: To reveal new records of island of Cozumel marine gastropods and bivalves. Methods: The specimens were collected mainly from transects in sandy substrates and revision of rocky surfaces. Results: Out of a total of 51 species of gastropods belonging to 39 genera and 23 families, and 11 species of bivalves belonging to 10 genera and nine families, nine species were registered as new records, six of gastropods and three of bivalves, which increases knowledge of the marine malacofauna of the region. The new records represent 11.76% and 27.27, respectively, of the total fauna of gastropods and marine bivalves known on the coasts of the island of Cozumel. The main malacogeographic affinity of the new records is the Caribbean. Conclusions: The study area has a 87.93% of the known marine gastropods for the state of Quintana Roo. The total marine bivalve species in the study area constitute 13.92% of the fauna of this mollusk class for the state. Although the main malacogeographic affinity of the new marine mollusk records is the Caribbean, the study area belongs to a transition zone with the Carolinean province. None of the new records is endemic. All the gastropod and bivalve species indicated as new records can be found in at least four malacological subprovinces.

RESUMEN Antecedentes: Los gasterópodos y bivalvos marinos son algunos de los grupos de invertebrados más diversos en la naturaleza, pero en México se requiere de un mejor conocimiento de su composición taxonómica. Aunque existen importantes estudios sobre los moluscos del Caribe mexicano algunas zonas como la isla de Cozumel han sido poco estudiadas. Objetivo: Difundir nuevos registros de gasterópodos y bivalvos marinos de la isla de Cozumel. Métodos: Los ejemplares se recolectaron principalmente a partir de transectos en sustratos arenosos y revisión de superficies rocosas. Resultados: De un total de 51 especies de gasterópodos pertenecientes a 39 géneros y 23 familias, y 11 especies de bivalvos pertenecientes a 10 géneros y nueve familias, se registraron nueve especies como nuevos registros, seis de gasterópodos y tres de bivalvos, lo que incrementa el conocimiento de la malacofauna marina de la región. Los nuevos registros representan el 11.76% y 27.27%, respectivamente, de la fauna total de gasterópodos y bivalvos marinos conocidos en las costas de la isla de Cozumel. La principal afinidad malacogeográfica de los nuevos registros es la Caribeña. Conclusiones: El área de estudio posee el 87.93% de los gasterópodos marinos conocidos para el estado de Quintana Roo. El total de especies de bivalvos marinos del área de estudio constituyen el 13.92% de la fauna de esta clase de moluscos para el estado. Aunque la principal afinidad malacogeográfica de los nuevos registros de moluscos marinos es la Caribeña, el área de estudio pertenece a una zona de transición con la provincia Caroliniana. Ninguno de los nuevos registros es endémico. Todas las especies de gasterópodos y bivalvos indicados como nuevos registros se distribuyen en al menos cuatro subprovincias malacológicas.

Abstract Background: The bivalve Aulacomya ater (cholga), is one of the most consumed mollusks by the population. However, there is evidence of fecal water contamination caused by causes that affect the sea, increasing the probability of contamination by the Cryptosporidium parvum, which generates cryptosporidiosis in people. Aim: To determine the presence of C. parvum in cholga extracted from the Bio Bio Region (Chile). Methods: Fifty-five cholgas were selected from a cultivation center and a natural extraction bank. These samples were processed in the laboratory and the presence of acid-alcohol resistant elements was evaluated. Positive samples were analyzed by direct immunofluorescence with anti-C. parvum antibody. Results: 16.4% of the total samples were affected by the oocysts of C.parvum. Conclusions: For the first time we described C. parvum in A. ater from the Chilean coast, being this mollusk a possible vehicle for transmission of cryptosporidiosis to the population and their predatory animals. Furthermore, the presence of C. parvum reflects fecal water contamination on the evaluated coasts. We are currently monitoring other extraction areas for this mollusk.

Resumen Introducción: El bivalvo Aulacomya ater (cholga), es uno de los moluscos de mayor consumo en la población chilena. Sin embargo, existe evidencia de contaminación fecal hídrica provocada por los cauces que llegan al mar, aumentando la probabilidad de contaminación por Cryptosporidium parvum, el que genera criptosporidiosis en el ser humano. Objetivo: Determinar la presencia de C. parvum en cholgas extraídas desde la Región del Bío Bío (Chile). Material y Métodos: Se seleccionaron 55 cholgas provenientes de un centro de cultivo y de un banco natural de extracción. Estas muestras, fueron procesadas en el laboratorio y se evaluó la presencia de elementos ácido-alcohol resistentes. Las muestras positivas, se analizaron por inmunofluorescencia directa, con anticuerpo específicos contra C. parvum. Resultados: 16,4% del total de las muestras tenían ooquistes de C. parvum. Conclusiones: Por primera vez se describe C. parvum en A. ater provenientes de las costas chilenas, siendo este molusco un posible vehículo de transmisión de criptosporidiosis a la población y a sus animales depredadores. Además, la presencia de C. parvum refleja la contaminación fecal hídrica en las costas evaluadas. Actualmente estamos monitoreando otras zonas de extracción de este molusco.

The production of fatty acid methyl esther (FAME) via transesterification was studied, assessing the influence of CaO heterogeneous catalysts obtained from four different fishery residues: sururu, crab, clam and mussel. Characterization and properties of the residues were obtained via thermogravimetric analysis, X-ray diffraction, X-ray fluorescence, Fourier transform infrared (FTIR) spectra, nitrogen adsorption/desorption, chemical composition and scanning electron microscopy (SEM). Catalytic activities and reaction kinetics of FAME synthesis from the transesterification of soybean oil were performed. FAME yield was determined by 1H nuclear magnetic resonance (NMR). A higher efficiency and reaction rate were observed for the catalysts obtained from the sururu residues with 93.7% FAME yield after 3.5 h of reaction at the first usage, reducing only to 91.0% after four consecutive cycles of reuse. The best activities were assigned to the presence of SrO, to smaller particle size, higher pore volumes and the higher Ca leaching, yielding Ca-diglyceroxide which is an important active phase for transesterification.

ABSTRACT This study estimated the population density of Spondylus limbatus at six fishing banks that are representative of the Gulf of California, Mexico. Each bank was identified in July 2011. There were significant differences in density between banks, and a steady north-to-south decrease in density that was fitted to a potential model. At low densities, S. limbatus showed a lower variability in size. Since the densities of S. limbatus are suitable for commercial exploitation, sustainable extraction can be performed under a population recovery approach. Also, this study represents a baseline for the evaluation and monitoring of populations of this species through time and contributes to set general guidelines for the assessment of commercial feasibility and exploitation criteria.

Norovirus (NoV) is the main cause of gastroenteritis outbreaks worldwide. Although NoV spreads mainly from person to person, it is estimated that a large proportion of NoV outbreaks are caused by foodborne transmission. Bivalve mollusks are one of the most important foods involved in NoV transmission to humans. Little is known about NoV prevalence in shellfish harvested and commercialized in Brazil. The aim of this study was to map, for the first time, the distribution of NoV contamination in oysters and mussels harvested and commercialized in the coast of Pernambuco state, northeast Brazil. A total of 380 mollusks (260 oysters and 120 mussels) were collected between February and August 2017 either directly from harvesting areas or obtained from beach vendors at 17 sites in Pernambuco. Samples were processed and tested for NoV contamination using a SYBR Green real-time PCR assay. All samples were negative for NoV GI or GII contamination, suggesting a low risk of NoV contamination from this food source during the study period. Additional surveys in different areas of the Brazilian coast are warranted to monitor the risk of NoV infection upon seafood consumption.

Abstract Sea anemones are considered as polyphagous opportunistic predators and it has been suggested that their diet reflects the structure of the community they inhabit. The feeding ecology of intertidal species is an interesting topic to study due to their wide variety of strategies to obtain food. In this sense, we studied the diet of Bunodosoma zamponii, the most abundant actiniarian in the rocky intertidal of Punta Cantera (Mar del Plata, Argentina). The objectives were to describe it and compare its composition seasonally and between diurnal and nocturnal high tides. We examined the gastric cavity content of 154 specimens collected seasonally at both diurnal and nocturnal high tides, and 39 different prey items were identified, some of which are recorded here for the first time for this species. No variations on diet composition were found between seasons or between diurnal and nocturnal high tides, suggesting that the food available does not vary either. Bunodosoma zamponii ingests mostly items with low biomass, which contribute to the total biomass ingested in direct proportion to their frequency in the diet. The bivalve Brachidontes rodriguezii was the main prey for the anemone, followed to a lesser extent by certain amphipods, other mollusks and algae.