[2] Species within the Solemya genus are distinguished by their reduced or absent guts and their association with symbiotic, chemosynthetic bacteria, which produce metabolic energy by oxidizing sulfide in order to fix carbon for their hosts.

Sulfur-oxidizing bacterial symbionts are intracellular, harbored in the epithelial cells of S. velum gills and the tissue appears yellow when freshly collected due to the build-up of these sulfuric compounds.

[5] The bacterial symbionts within S. velum and other Solemya species are chemoautotrophic, able to fix Carbon by using chemical energy from sulfur oxidation reactions and taking up CO2.

The presence of these clams and their symbionts in areas with high woody debris or sewage is critical in cycling carbon and breaking down sulfur compounds, reducing the toxicity of near-anoxic sediments.

The carbon-fixation capabilities of S. velum symbionts are an active area of research for the importance of CO2 consumption in marine carbon cycling.