Marine flora refers to the plant life found in the ocean, and one of the most common types of marine flora is ALGAE. ALGAE are a type of simple, photosynthetic organism that can range from single-celled organisms to complex multicellular forms. They are found in all types of aquatic environments, including oceans, rivers, and lakes. ALGAE are an important part of the marine food web, providing food for many species of fish and other marine animals.