Non-native species have been introduced at escalating rates during the last decades, mainly due to the dispersion generated by the increasing trade and transport worldwide. Mollusks, the second largest metazoan phylum in terms of species richness, are no exception to this pattern, but, to date, a comprehensive synthesis of non-native mollusk species (NNMS) in South America was not available. For this purpose, an e-discussion group was formed with malacologists and taxonomists from South America, where we exchanged and analyzed bibliography, databases and information about NNMS, providing expert opinion to this assessment. The first list of non-native mollusk species for South America, considering terrestrial, freshwater and marine environments, includes 86 NNMS distributed in 152 ecoregions (terrestrial, freshwater and marine) of the 189 recognized for the South American continent. Information on their native region, vectors, first record for South America and distribution, are also provided. In the analysis of the distribution of the NNMS and the entry points of each species (e.g., ports, cargo and passenger airports, cities) and status of conservation of the ecoregions, four hot spots were recognized: Subtropical-Atlantic,
Testing a molecular protocol to monitor the presence of golden mussel larvae {Limnoperna fortuna) in plankton samples
Limnoperna fortunei (Dunker, 1857) is an invasive freshwater bivalve native to rivers and streams of China and Southeast Asia. In 200 1, it was discovered in Itaipu Reservoir, and its population has grown considerably since then. The aim of this study was to estimate density, recruitment, and individual growth of L. fortunei in a subtropical region from a field experiment using an artificial substrate. Samples were collected between December 2004 and December 2005 at Bela Vista Reservoir in Foz do Iguagu, Brazil. Mussels were counted and measured to generate size-frequency and distribution data. Maximum and minimum densities (* standard deviation) were 204 i 17 ind. 100 cm-2 and 94 * 22 ind.lOO ~m -~, respectively. Shell length ranged between 1 and 36 mrn, and shell length frequency indicated presence of young mussels with variable densities throughout the period surveyed. The von Bertalanffy model fitted successfuHy in all cases explaining more than 96% of the variation in shell length. Measured growth parameters (k = 2.35 L, = 38 rnm) were different from those estimated for populations of L. fortunei in a temperate region.
Recebido em 6/5/08; aceito em 16/10/08; publicado na web em 12/2/09 BIOFOULING AND CHEMICAL BIODETERIORATION IN HYDROELETRIC POWER PLANT PORTLAND CEMENT MORTAR. Last decade Brazilian rivers experimented progressive biofouling of Limnoperna fortunei communities and Cordylophora caspia hydroids. The microhabitat is so favorable that in around 1.5 years L. fortunei increased from 0.39 to nearby 149,000 units/ m 2 . Ten Portland cement mortar samples were produced with 1: 3.5: 0.4 dosages and installed for 1 year at Salto Caxias Brazilian Power Plant reservoir in 0.5 m and 1.0 m deep to investigate the biofouling influence on hydraulic civil structures. SEM, EDS, visual investigation and XRF results indicate none direct chemical interrelationships between L. fortunei and the mortar samples. However C. caspia diminished the mortar surface resistance and caused cement paste leaching.Keywords: Portland cement mortar; biofouling; Limnoperna fortunei. introduçãoAs estruturas de concreto das áreas de geração hidroelétrica necessitam ter resistência mecânica suficiente para suportar o próprio peso e, principalmente, as cargas ocasionadas pela retenção e canalização das águas para movimentação das máquinas hidráulicas. Com este objetivo, grandes reservatórios são produzidos, constituindo meios ideais para a proliferação de micro e macroorganismos, tais como as espécies exóticas do hidrozoário Cordylophora caspia e do molusco Limnoperna fortunei, conhecido como mexilhão dourado, atualmente disseminadas pelos rios e reservatórios brasileiros. Estes organismos encontram-se presentes no reservatório da Usina Hidroelétrica Governador José Richa (UHE GJR) ou UHE Salto Caxias, a cerca de 600 km de Curitiba. A região vem sendo tão propícia à sua fixação e evolução que, em menos de um ano e meio, a densidade populacional dos mexilhões dourados cresceu de 0,37 para cerca de 149.000 indivíduos/m 2 , com diâmetro médio de suas conchas em torno de 36 mm. 1,2 Pode-se, desta forma, inferir sobre a seriedade do problema gerado a estes empreendimentos.A bioacumulação ou biofouling, termo que se refere à formação de depósitos biológicos sobre a superfície de equipamentos ou instalações industriais e, neste caso, de superfícies hidráulicas, pode trazer como conseqüência efeitos deletérios adversos. Destacam-se os processos corrosivos ou bioeletroquímicos e a diminuição da vazão ou entupimento de adutoras e dutos, principalmente se estes são responsáveis pela refrigeração hidráulica de máquinas rotativas que operam sob baixas temperaturas, como as turbinas para a geração de energia elétrica. Além disto, tem-se a possibilidade de que a fixação destes organismos cause alterações químicas superficiais ou biodeterioração, em virtude de seus processos metabólicos com geração de substâncias poliméricas extracelulares e secundárias, tais como os ácidos orgânicos. 3 No reservatório da UHE GJR, o biofouling vem ocorrendo, principalmente, sobre a grade da tomada de água e nas paredes de concreto das câmaras das comportas de descarregamento do reservatór...
The genus Mytilus comprises a large number of bivalve mollusk species distributed throughout the world and many of these species are considered invasive. In South America, many introductions of species of this genus have already taken place, including reports of hybridization between them. Now, the occurrence of the Mediterranean mussel Mytilus galloprovincialis is reported for the first time from the Brazilian coast. Several specimens of this mytilid were found in a shellfish growing areas in Florianópolis and Palhoça, Santa Catarina State, Brazil. Morphological analysis of the shells and molecular analysis through sequencing of the cytochrome oxidase subunit 1 (COI) confirmed the taxonomic identification. The species is known for its great invasive potential and can become a major environmental problem for seafood business and coastal communities, as it can compete and even hybridize with local species.
Exotic species are those that occur in an area beyond their natural limit and they are considered invasive when they cause harm to the economy, environment, or human health. In coastal environments, ballast water and inlays on the hull and other parts of vessels are the main ways of introducing invasive aquatic alien species. Nassarius foveolatus (Dunker, 1847) is native from the Central and East Indian Ocean to the East China Sea. The first specimens (empty shells) of N. foveolatus were collected manually on November 11, 2017 on the Rocio footbridge, located in the Paranaguá Estuarine Complex, on the coast of the State of Paraná, southern Brazil. Posteriorly, live specimens were collected in other localities of this bay. It is already possible to infer that the specimens of N. foveolatus occur together with the native specimens of N. vibex (Say, 1822), having the same niche. As previously only N. vibex existed in that place, at least a displacement of this native species has been occurred. However, certainly future ecological studies may confirm this displacement and additional consequences to the local ecosystem, as nassariids can be predators and scavengers. Control procedures should be also greatly implemented.
The new bulimulid species, Drymaeus currais sp. nov., is described based on shell and anatomical features. It is endemic of Guapirá Island, belonging to the Currais Archipelago, a small protected area off Paraná coast. The species is thus, based at least on endemicity, endangered. It has as closest species D. castilhensis, another endemic species of Castilho Island, ~70 km northwards. Its main exclusivities are a banded shell (except for periumbilical area); a ureter ~1/3 opened (furrow); an external anus; a slightly different buccal and intestinal arrangement; a penis lacking internal chambers; a small receptacle with a genital appendix. Zoobank Register: urn:lsid:zoobank.org:pub:25B25A8B-CED0-4284-A799-5383998BE481.
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