We redescribe type specimens of two freshwater mussels from Brazil, Diplodon ellipticus Spix in Wagner, 1827 and Diplodon expansus (Kuster, 1856), focusing on previously unnoticed diagnostic ...conchological aspects in a brief taxonomical review. The first species, represented by one shell previously considered to be lost, was recently rediscovered in the collection of the Zoologische Staatssammlung Munchen, Germany, and identified as the figured holotype. Material of the second species, deposited at the Charpentier Collection at the Musee de Zoologie Lausanne, Switzerland, was discovered to be a syntype series. The lectotype and paralectotypes of D. expansus were selected.
Cyanocyclas brasiliana (Deshayes, 1854) known only from the original very short description and reported from Pará state was recently rediscovered. This is the first occurrence of a native species of ...Cyrenidae (formerly Corbiculidae) in the Northeast Region of Brazil. Due to a lack of previous data C. brasiliana was initially confused with Corbicula largillierti (Philippi, 1844), an invasive species of Asian origin, which was introduced in South America in the 1970s and already recorded from the North and Northeast regions of Brazil. Ecological aspects are described. To aid identification, type material was studied.
The golden mussel (Limnoperna fortunei, Mollusca: Mytilidae) is an emerging invasive species in freshwater environments in South America, causing extensive environmental and economic impacts. A ...molecular method to detect larvae of the golden mussel in plankton samples has been recently developed and holds promise for becoming an important way to monitor the expansion of golden mussel populations. In the present study, we conduct, for the first time, field tests of this method by comparing its performance with alternative sampling efforts (microscopy and manual search for adults). In addition, we test different modifications of the molecular method to deal with PCR inhibition in environmental samples. The results indicate that the molecular method is very efficient, being faster and more sensitive that microscopy methods. Therefore, the molecular method tested in the present study can represent an invaluable tool in large-scale monitoring efforts of the golden mussel throughout its introduced range.
The movement of species is among the most serious environmental threats of the new millennium, as the transplantation of species beyond their native or historical range has intensified in the last ...five decades. Traditionally, studies on bioinvasions have focused on species that have been introduced, deliberately or accidentally, to biogeographic regions where they did not previously occur. However, less attention has been given to species movement to novel areas within the same biogeographic region. Our research group, the South America Introduced Molluscs Specialists, analyzed potential cases of native South American mollusc species introduced deliberately or accidentally beyond their natural range within South America. To achieve this, it is key to differentiate between anthropogenic processes and passive responses to environmental conditions. We considered the past and current spatial distribution of species, analyzed known or putative vectors, and discuss the impacts of taxonomic and nomenclatural knowledge. Based on the evidence currently available, we propose different scenarios to explain observed changes in mollusc distributions within South America. Seventeen transplanted mollusc species (TMS) were recognized, considering marine, freshwater, and terrestrial environments. Of the 189 South American ecoregions 31 were occupied by transplanted species, but this proportion varied by environment: 10 of 28 marine ecoregions, 12 of 52 freshwater ecoregions, and 9 of 109 terrestrial ecoregions. The ecoregions with TMS are generally located in the peripheral zones of the continent. Those with the highest number of TMS were the Southern Caribbean (three species) in the marine environment, the Central Andean Pacific Slopes (three species) in the freshwater environment, and the Alto Paraná Atlantic forests (two species) in the terrestrial environment. The number of unintentionally moved TMS is greater than those moved intentionally. The transplantation process is similar to the introduction and settlement process of non-native mollusc species, and so is their impact.
Human beings are actively exposed to ultraviolet (UV) radiation, which is associated with skin cancer. This has encouraged the continuous search for more effective and safer photoprotective ...formulations. Along with the application of traditional organic sunscreens, there is a growing interest in “green products” containing natural compounds such as plant extracts and oils. This trend is combined with the use of nanotechnology as a tool for optimizing the vehicles of such compounds. Nanoemulsions (NEs) are suitable for the encapsulation of natural compounds, which improves topical treatment. Therefore, we have developed oil-in-water (O/W) nanoemulsions containing 3% buriti oil (BO), incorporated in a 10% vegetal extract of Aloe vera (AV) by means of ultrasonic processing to improve the chemical characteristics of this component and, consequently, its efficacy and safety in pharmaceutical and cosmetic formulations. The composition of the formulation was initially defined in a preliminary study on surfactants where the concentrations of Tweensup.® 80 and Spansup.® 20 were evaluated in relation to particle size and the polydispersity index (PDI). The nanoemulsion was prepared and then chemical sunscreens were incorporated with the aim of developing a sunscreen nanoemulsion called NE-A19. This nanoemulsion was found to be the best formulation due to its stability, droplet size (146.80 ± 2.74), and PDI (0.302 ± 0.088), with a monomodal size distribution. The stability was evaluated over 90 days and showed a low growth in particle size at the end of the study. NE-A19 exhibited good viscosity and organoleptic properties, in addition to an occlusion factor indicating an interesting and higher water holding capacity when compared with a NE without AV (p < 0.05). The in vitro efficacy and safety studies of NE-19A were promising. Its average in vitro sun protection factor value was 49, with a critical wavelength (λsub.c) of 369.7 nm, satisfactory UVA protection, and a UVA/UVB ratio of 0.40, indicating broad spectrum protection against UVA and UVB radiation. Furthermore, NE-19A displayed a good safety profile in dermal keratinocytes. It can be concluded that NE-19A is a promising formulation for carrying natural products, such as buriti oil and AV, associated with synthetic filters in lower concentrations.
The ceramic substrate (21cm in length, 6cm in width and 1.3cm in depth) was tested for the Limnoperna fortunei population, sampling at two localities in the Jacuí delta (Jacuí Canal (Canal do Jacuí – ...CJ) and Port Docks (Cais do Porto – PO)) in Rio Grande do Sul state, Brazil. The individuals were quantified through the superimposition of a squared (1cm2) and segmented (sI, sII e sIII) sheet on the substrate. Using Kruskal-Wallis and Mann-Whitnney, the recruit and adult average densities were compared in each segment, surface (smooth and pipe-shaped) and sampling locality (α = 0.05). In CJ, the extreme and intermediate (adult) segments differed statistically (p < 0.0001), as well as the ceramic substrate surfaces (recruits) (p = 0.04). The recruit and adult densities between the CJ and PO localities also differed between themselves (p < 0.0001). The method was efficient for the invasive population sampling.
Sphaerium cambaraense new species is described based on samples collected in the beginning of the summer near the headwaters of Taquari River (Jacui River Basin) on the basaltic plateau of southern ...Brazil. This is the first record for the genus Sphaerium in Brazil and in South America outside the Andes. Sphaerium cambaraense is characterized by a relatively large and solid shell, a high triangular shell outline and a solid hinge plate. Compared with Sphaerium forbesi (Philippi, 1869), S. cambaraense has a more strongly triangular shell outline and beaks not prominent. Sphaerium lauricochae (Philippi, 1869), another similar species from Bolivia, Chile, and Peru, has a more rounded shell outline.
Objetivando avaliar a ocorrência de invertebrados associados aos macroaglomerados de Limnoperna fortunei (Dunker, 1857) sobre galhos de sarandi (Chephhalanthus glabratus (Spreng.) K. Schum) foram ...realizadas coletas qualitativas (N=28) no período de 2002 a 2004, na Praia do Veludo, lago Guaíba (Porto Alegre, RS). Destacaram-se os gastrópodes Heleobia piscium (Orbigny, 1835) (78,57%), como espécie constante nas amostras; Potamolithus jacuhyensis Pilsbry, 1899 (35,71%), como espécie acessória e o crustáceo Hyalella curvispina Shoemaker, 1942 (26%), como espécie acessória. Os demais táxons foram acidentais (<25%): Ampullariidae (indivíduos jovens); Heleobia davisi (Silva & Thomé, 1985); Chilina parva (Martens, 1868) e Corbicula fluminea (Müller, 1774). As relações interespecíficas destes táxons são até o momento pouco conhecidas.
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