Mytilus

Mytilus is a genus of medium-sized marine bivalve molluscs in the family Mytilidae. Species within the genus are commonly known as mussels and are found in temperate coastal waters around the world. Notable members include Mytilus edulis (blue mussel), M. galloprovincialis (Mediterranean mussel), M. trossulus (Pacific blue mussel), M. californianus (California mussel), and M. chilensis (Chilean mussel). They inhabit intertidal to subtidal zones on hard substrates such as rocks, pilings, and other shells, often forming dense beds.

Mussels have two hinged shells and attach to substrata by byssal threads secreted from their foot. They are filter feeders, drawing water through incurrent siphons to extract phytoplankton and organic matter, and expelling filtered water through excurrent siphons. Shells are closed by adductor muscles, and the animals can retract when threatened or desiccated.

Reproduction is typically external. Females release eggs and males release sperm into the water column, where fertilization occurs. Free-swimming larvae (trochophore and veliger stages) are planktonic for several days to weeks before settling and metamorphosing into juvenile mussels that attach with byssal threads.

Ecology and human use: Mussel beds are important for ecosystem function, filtering large volumes of water and providing habitat. They are also economically significant, cultivated and harvested worldwide for food. Aquaculture methods include rope- or longline-based culture and raft systems. In some regions, introduced populations have affected native communities, and disease and pollution can impact stocks.

Conservation and management focus on sustaining wild populations, monitoring water quality, and regulating harvest and aquaculture practices to reduce environmental impacts.