Bivalves · Ostreida · Isognomonidae

Flat Tree Oyster

Isognomon alatus

Not Evaluated

It has not yet been assessed against the IUCN criteria. See full glossary

A flattened, irregular bivalve that attaches by its byssus to the submerged roots of red mangroves and to piles and rocks, often in dense clusters. It filters phytoplankton and copes well with the swings in salinity of the mangroves.

Size

5 cm – 10 cm

Diet

Omnivore

Combines animal and plant food depending on availability.

Social structure

Colony

Lives in large concentrations, often for breeding reasons.

Sighting difficulty

Unknown

OceanOmnivore Colonial Ocean Mollusc

34countries 24parks 12dive sites

Fun facts

Its clusters on mangrove roots create microhabitat for crabs, worms and juvenile fish.
The straight hinge with a row of parallel grooves makes its valves very easy to identify on the beach.
It forms dense clusters on the aerial roots of red mangrove, one of the characteristic features of the mangrove community.
Its shell is highly compressed, flattened and irregular, and takes the shape of whatever it attaches to.
It is a filter feeder tolerant of the variable salinity of mangroves and of exposure to air at low tide.
It has been used as a biomonitor of heavy metals in Caribbean coastal waters.