In common with other bivaves of the family Lucinidae, Rasta lamyi lives in a symbiosis with bacteria which are housed in special cells within the large fat gills. The bacteria live by oxidising dissolved hydrogen sulphide from sediment water. Rasta is dependent on the bacteria for most most of its nutrition. The long extensions from the shell are actually pipes through which water from the surrouding sediment is pumped into the bivalve body cavity to supply the bacteria in the gills.