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DISSEMINATION ![]() |
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Kingdom | Animalia |
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Phylum | Mollusca | |
Class | Bivalvia | |
Order | Mytiloida | |
Family | Mytilidae | |
Genus | Mytilus | |
Species | galloprovincialis | |
Classification | Lamarck, 1819 | |
Common name | bay-mussel |
Geographic Range | it is found in the Mediterranean Sea, in the Black Sea, in the Atlantic. |
Physical Characteristics | the shell is divided into two equal valves and it is made up of the calcium carbonate that the mollusc extracts from the water. It is elongated. The part towards the umbo is point-shaped, while the border on the back is round-shaped. Observing a bay-mussel well, one can notice thin concentric circles representing the phases of growth of the shell. The colour of the surface is black- bright violet, the inside is pearly. It lives stuck onto hard surface thanks to filaments produced by the byssus gland. The filaments are made up of ceratine which solidifies when it is in contact with the water. The pallium, which is visible inside the shell, has a violet border and includes the internal organs. |
Notes | it is a filter feeder and a “bioaccumulator”: that is why it is a good indicator of the quality of the waters. It can resist out of the water for many days. The pallium changes in the colour and in the look depending on to the stage of sexual maturity of the mollusc: from yellowish white, typical of the period of sexual rest, to cream yellow in the males and orange-red in the females during sexual maturity when the emission of the gametes occurs. |
Habitat | it is found in the tidal zones. |
Food habits | being a filter feeder, it feeds on plankton and on suspended organic particles. |
Reproduction | it reproduces between March and June and at the beginning of the spring the larvae stick onto the substratum. After about 6-8 months from the moment in which they stick to the substratum the molluscs start the phase of sexual maturity. Both male and female gametes are put in the water and there the insemination takes place. The larva passes through several stages and during the last one, when it is finally adult, it gets stuck thanks to the byssus. |
Sources | |
References | Riserva Naturale Marina di Miramare Federazione Nazionale delle Imprese di Pesca Federcoopesca |
Web References | http://www.univ.trieste.it/~wwfmiram/index.html http://www.iniziativapesca.federpesca.it/ http://www.federcoopesca.it/ |
Source of the photo | www.toyama-u.ac.jp/~nakamura/ photostudy.htm |