Transcript Spread in Italy

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It is a large mollusk three
times his Italian “relatives”;
it can reach a length of
fifteen centimeters.
Anodonta Woodiana is very
pulpy and the shell’s inside
is full of nacre. It’s good
looking iridescent despite
of the exterior trivial color
of sand streaked with black.
Spread in Italy
Anodonta Woodiana was found for
the first time in Italy in 1989-90,
inside a lot of rivers in Emilia
Romagna; in a couple of decades it
has spread throughout Italy and
other findings were then followed
in Lazio (1998), Tuscany and
Veneto (2003), in Marche,
Piedmont, Umbria and Lombardy
(2006). In 2004 were fished out
three specimens on the banks of
Arno in Florence.
It's of Indonesian origin and the specimens found in Arno and in other tuscan
rivers probably come from China.
How it spreads
This is an alien species that has invaded rivers, streams and
waterways, being foreign to the ecosystem of the areas.
The introduction of the Anodonta woodiana can be defined
as "involuntary human" because it is related to the placing
of fish for breeding purposes and / or restocking.
Unionidi's larvae (glochids) parasitize in fact the fishes' fins
or gills by attaching with a sort of hook; later they detach from the host and
fall to the bottom, where they mature and start to lead a life of freedom.
These bivalves are so able to expand their range of distribution colonizing
other areas.
Consequences of the spread
It is to some extent also a threat, as it seems to threaten the
survival of native species such as Anodonta Anatina and other
smaller.
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Its function is that of all the shellfish, which is to filter water, so
its spread is not so much dangerous in itself as to the consequences it
may have on the survival of other species.
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First colonies: Southeastern Russia, China, Japan, Cambodia, Thailand,
Malaysia and Taiwan.
• From 1984 to 2000: Hungary, Romania, France, Slovakia, Czech Republic,
Austria, Poland.
• In Italy, from 1999 to 2006: Emilia Romagna, Lazio, Tuscany, Veneto, Marche,
Piedmont, Lombardy and Umbria.