The swan mussel has a thin fragile shell. It is found in fresh stationary waters. It has a foot so that it maneuver a bit. There is one known incident of a swan. Descriptions and articles about the Swan Mussel, scientifically known as Anodonta cygnea in the Encyclopedia of Life. Includes Overview; Brief Summary; Distr. Anodonta-cygnea_jpg. Anodonta cygnea. Provided by Welter Schultes, Francisco Locality: Germany: Schleswig-Holstein, Brammer Teich near Kiel.
|Published (Last):||21 August 2005|
|PDF File Size:||19.45 Mb|
|ePub File Size:||11.41 Mb|
|Price:||Free* [*Free Regsitration Required]|
A very large bivalve shell found in silty or muddy backwaters of streams, rivers and lakes. They have a strong pungent odor and are used by carp fisherman as bait.
Wikimedia Commons has media related to Anodonta cygnea. The swan mussel is a very large bivalve mollusc which lives in streams, rivers and along lakeshores where the bottom is of rich mud or silt and relatively free of plant growth. Threatened by continuous destruction of habitats, water current regulations, exaggerated pollution by fertilizers, also by natural drying out of waters.
The parasitic larvae are called glochidia and are produced in spring and carried by the current until they contact a bottom-living fish. It differs from Anodonta anatina in being larger shell with straighter, more parallel dorsal and ventral margins; the growth lines of the inner, oldest part of the shell are finer and shallower, and reach the margin. Why is this species a priority in Northern Ireland?
In other projects Wikimedia Commons. On a still, sunny day after a period of dry weather look down at the lake bottom with Polaroid glasses or using a glass-bottomed box.
Anodonta cygnea Linnaeus The outlines of shells poking out of the mud can then be seen with the paired pale siphons appearing between the valves. They will then drop off after a period of weeks and find a suitable place on the bottom to begin an independent life. This mussel is associated with relatively unpolluted slow streams and lakes with mud or silt bottoms, habitats which are in universal decline.
This is smaller though still a large shell at mm long but usually with a more distinctly angular shape. Swan mussel shells appear to be of even thickness throughout, whereas duck mussel shells are clearly uneven and much thicker and opaque towards the lower front end of the shell.
Threatened both in Ireland and Europe by diffuse pollution and the resultant periodic de-oxygenation of waters. Wnodonta history of this page. Life cycle Adults are long lived and there is nearly always a good proportion of mature shells present in colonies.
WoRMS – World Register of Marine Species – Anodonta cygnea (Linnaeus, )
Breeding depends upon the presence of reasonable water quality and of fish. How cyhnea see this species Swan mussels can sometimes be seen from fishing stands at the margins of lakes with silty or mud bottoms.
There was a problem providing the content you requested
Swan mussel Conservation status. Views Read Edit View history. In this way large beds of anodonnta mussel along the Shannon and Erne River systems have perished and enormous numbers of empty shells cast ashore. Tolerates eutrophic conditions, but not in the last toxic stadium.
Nomenclator Zoologicus Neave updated, genera. Glochidia are mature in autumn, are released in spring in England and in Italytheir size 0.
Retrieved from ” https: The shell is thin and pale, whitish or pearly inside due to a thin layer of nacre, but protected by a periostracum outside which gives it a smooth, glossy brown, sometimes green appearance marked with strong concentric growth lines. Support environmental schemes aimed at reducing diffuse pollution whether from agricultural sources, from inadequate sewage treatment in towns or from the malfunctioning or failure of septic tanks in rural areas.
The zebra mussel impacts swan mussels indirectly, by settling on their shells which provide the only hard substrate in many waterways.
Malacologica Bohemoslovaca in Czech. This species is found in rivers and lakes. Archived from the original on 14 February It can reach mm 6 in in size ycgnea has a nearly straight dorsal upper or hinge margin with a drawn out posterior end and slightly rounded to nearly straight ventral lower margin. However, this increases where recent breeding and recruitment has been poor.
List of failure reports. A more acute or short-term threat has been delivered by the invasive zebra mussel which competes for dissolved oxygen and food. The Swedish Museum of Snodonta History.
AnimalBase :: Anodonta cygnea species homepage
Putting a valve of the shell up to strong light separates these two species. Institute of Zoology, Slovak Academy of Sciences. List of all species. Artificial lakes are usually cygnsa when anodonnta fishes are brought in, young mussels are rarely dispersed by water birds.
The swan musselAnodonta cygneais a large species of freshwater musselan aquatic bivalve mollusc in the family Unionidaethe river mussels. Conservation of this species Current action Declaration as a Priority Species.