Codium tomentosum Stackhouse is a species of green algae, most commonly known as velvet seaweed or also velvet horn, that belongs to the family Codiaceae. This green algae has the ability to reproduce asexually, through fragmentation, and sexually, and stands out for its wide and sponge-like fronds, that can grow up to 10 to 30 centimeters in length. C.tomentosum is most commonly found in coastal regions, especially in the Atlantic Ocean or the Mediterranean Sea. This species is harvested for its antioxidant and antimicrobial properties, and is used in pharmaceutical, cosmetic and food industries.