Phylum: Mollusca

Class: Bivalvia

Order: Mytiloida

Family: Mytilidae

Scientific name: Modiolus modiolus

 

Norwegian: O-skjell

(Flakk - The Trondheim fjord / 15 meters / 7.06.2001)

Distribution: Like the common mussel, the horse mussel thrive on hard surfaces, using the byssus threads to attach themselves. The horse mussel lives deeper, often on 10-25 meters. It has been reported as deep as 280 meters. The mussel does not mind current exposure and are also flexible with respect to temperature and salinity.

Characteristics: The horse mussel grows bigger than the common mussel. It can reach a length of 20 cm. The juvenile shells are often blue, but they tend to turn brown as they grow older.

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