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):||15 August 2016|
|PDF File Size:||18.79 Mb|
|ePub File Size:||16.70 Mb|
|Price:||Free* [*Free Regsitration Required]|
Views Read Edit View history. 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.
Anldonta 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. Down, BT18 0EU; cedar. Lakes, old river arms, artificial lakes, needs silent waters, only rarely in running waters, usually in lowlands.
There was a problem providing the content you requested
In brief A very large bivalve shell found in silty or muddy backwaters of streams, rivers and lakes Threatened both in Anodontz and Europe by diffuse pollution and the resultant periodic de-oxygenation of waters A more acute or short-term threat has been delivered by the invasive zebra cygnew which competes for dissolved oxygen and food Red listed in Ireland as Vulnerable VU and as a Anodknta Species in Northern Ireland Species description A very large bivalve shell with a flattened profile and broad, oblong shape.
Tolerates eutrophic conditions, but not in the last toxic stadium. Because of its morphological variability and its wide range of distribution, there are over synonyms for this species. Click on map to open large map in new window. Retrieved from ” https: Diffuse pollution has affected its habitat in most areas and dissolved oxygen is reduced in many to dangerously low levels in the summer months.
Why is this species a priority in Northern Ireland?
IUCN Red List of Threatened Species
Nomenclator Zoologicus Neave updated, genera. Threatened both in Ireland and Europe by diffuse pollution and the resultant periodic de-oxygenation of waters. This is smaller though still a large shell at mm long but usually with a more distinctly angular shape.
The swan musselAnodonta cygneais a large species of freshwater musselan aquatic bivalve mollusc in the family Unionidaethe river mussels. From Wikipedia, the free encyclopedia.
List of all species. Life cycle Adults are long lived and there is nearly always a good proportion of mature shells present in colonies. An annotated list of the land and freshwater Mollusca of Northern Ireland. A very large bivalve shell found in silty or muddy backwaters of streams, rivers and lakes. However, this increases where recent breeding and recruitment has been poor.
Archived from the original on 27 December Threatened by continuous destruction of habitats, water current regulations, exaggerated pollution by fertilizers, also by natural drying out of waters. The zebra mussel impacts swan mussels indirectly, by settling on their shells which provide the only hard substrate in many waterways.
Occasionally found in Spain and Portugal in artificially disturbed habitats, where infected fishes from central Europe were released.
List of failure reports. Retrieved 4 January This page was last edited on 4 Octoberat Prefers muddy substrate bare of vegetation. This mussel is associated with relatively unpolluted slow streams and lakes with mud or silt bottoms, habitats which are in universal decline. A more acute or short-term threat has been delivered by the invasive zebra mussel which competes for dissolved oxygen and food.
Its native distribution is European-Siberian. How to see this species Swan mussels can sometimes be seen from fishing stands at the margins of lakes with silty or mud bottoms. 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.
The dorsal upper margin usually lies at an acute angle to the line of the ventral lower margin giving the shell a distinct wedge shape, instead of being almost parallel as cynea the swan mussel which produces a more oblong shape.
Malacologica Bohemoslovaca in Czech. 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.
Home Introduction Selection Criteria:: It can reach mm 6 in in size and has a nearly straight dorsal upper or hinge margin with a drawn out posterior end and slightly rounded to nearly straight ventral lower margin. Wikimedia Commons has media related to Anodonta cygnea. Anodonta cygnea Linnaeus The story may not end there, however, as the zebra mussel infestation is now waning and there is hope that the swan mussel can anoxonta some of the territory lost to its competitor.
In other projects Wikimedia Commons.
WoRMS – World Register of Marine Species – Anodonta cygnea (Linnaeus, )
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 cygena 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. Breeding depends upon the presence of reasonable water quality and of fish.
Shell yellowish or greenish brown, cygneq, not very solid, ligament long and narrow, without teeth, lower side of frontal interior margin not thickened. Retrieved 23 April The Swedish Museum of Natural History. Show history of this page. Embryonal shell finely striated along the growth lines, the lines reach the margin.
Archived from the original cgnea 14 February