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The invasive Asiatic freshwater bivalve Corbicula fluminea is regarded as a pest in several countries including Brazil. Two water birds native to South America, the limpkin Aramus guarauna and the common gallinule Gallinula galeata, are herein recorded preying on C. fluminea in a pond of an urban park in South-eastern Brazil. The exotic clam is becoming increasingly common in the diet of both these water birds. This trend is likely due to its increasing population and the consequent rarity of the habitual prey (apple snails and native clams) for the mollusc-specialised limpkin, besides being an accessible animal protein source for the omnivorous gallinule.
So far in Poland, the Asian clam Corbicula fluminea has been reported from the Oder (Odra) and Vistula River. Its new population has been discovered in the Warta-Gopło Canal in Konin (central Poland), where water temperature can reach 34°C, as the canal is a part of a power plant lake cooling system. The spatial distribution of C. fluminea was found to be very uneven and that is probably why this species was not found during earlier research. The highest density of C. fluminea was 78 ind.·m⁻² at the site where water flow was the fastest (2.49 m·s⁻¹), providing sufficient oxygenation of the water. The results suggest that existing information about the distribution of C. fluminea may be far from complete because the clam can be present also in the habitats that were not regarded as suitable for the species according to earlier reports, and therefore have not been monitored for its presence.
Live specimens of the gulf wedge clam (Rangia cuneata) were for the first time found in the Polish part of the Vistula Lagoon in 2011. The species is native to the Gulf of Mexico and the Atlantic coast of North America. First records of its introduction in Europe were reported in 2005 from Belgium and then in 2010 from the Russian part of the Vistula Lagoon.
The presence of the barnacle (Balanus improvisus) on the soft-shell clam (Mya arenaria) is reported for the first time from the Baltic Sea.
Ruditapes decussatus and Venerupis pullastra are commercially fished clams with a wide distribution in the shallow inshore waters of Lake Timsah, Egypt. They are usually contaminated with heavy metals. Consumption of such contaminated clams can pose a public health risk. To minimize this risk, therefore, the clams should be removed from the contaminated waters and transferred to an approved area to reduce the high levels of metals before being marketed. The aim of this work was to study the effect of transplantation on levels of heavy metals (Fe, Mn, Zn, Cu,Ni, Co,Cd,Pb) in these clams. The clams were removed from their polluted site and transplanted to a relatively clean area for a period of 120 days. Although the salinity at the transplantation site was higher than at the polluted site, it was stable and did not appear to have any adverse effect on clam growth. Heavy metals were analysed in the water, sediment and clam tissues from both the polluted and the transplantation sites. Although in both species transplantation evidently reduced heavy metal levels, these still exceeded the maximum permissible levels laid down by the WHO (1982).
Two cercariae, one of them ocellate and with well developed tail (Monorchiidae) and another apharyngeate brevifurcocercous (Aporocotylidae), parasite of Amiantis purpurata (Lamarck, 1818) (Bivalvia, Veneridae) from the Patagonian coast on the Southwestern Atlantic Ocean, are described. These reports comprise the second monorchiid intramolluscan infection reported for the Southern Hemisphere and first intramolluscan aporocotylid for the Southern Hemisphere. In addition, this constitutes the first report of aporocotylid intramolluscan stages (parthenita) occupying only the haemocoel of the gills of a marine molluscan host rather than the digestive gland and gonad, the usual site of infection.
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