Planaria are flatworms belonging to the class Turbellaria. They are commonly found in freshwater environments, such as ponds and streams. Planaria are known for their distinctive flat bodies and can range in size from a few millimeters to several centimeters. They have a simple body structure, with a head that features two eye spots and a mouth located on the underside. These organisms are famous for their remarkable regenerative abilities. If a Planaria is cut into pieces, each piece can regenerate into a complete worm. This unique trait makes them a subject of scientific research, particularly in studies related to regeneration and developmental biology.