Planarians often have an ear-like projection on each side of their body beside their eyes. These projections are called auricles. They don’t play a role in hearing as their name might suggest but instead contain chemoreceptors to detect chemicals. They are also sensitive to touch.Click to see full answer. Then, do planarians have a heart?Planaria are free-living flatworms that live in quiet ponds or bodies of water. The most common species studied in the lab is the brown planaria, Dugesia. The animal has an acoelomate body (no internal cavity to hold organs), no anus and lacks a circulatory system.Also, do flatworms have eyes? You’ll learn about a few classic examples of flatworms in your classes. They are freshwater flatworms that have a head like an arrow. They’re black with two white spots on their heads. Those spots are not eyes, but they do sense light. In this way, do planarians have eyes? Planaria exhibit an extraordinary ability to regenerate lost body parts. For example, a planarian split lengthwise or crosswise will regenerate into two separate individuals. Some planarian species have two eye-spots (also known as ocelli) that can detect the intensity of light, while others have several eye-spots.Do Planarians feel pain?TRPA1 is best known as the “wasabi receptor” in humans and as a sensor for environmental irritants giving rise to the sensation of pain and itch. In their study, Gallio and colleagues discovered that the simple planarian also possesses TRPA1 and that, like in humans, it controls the responses to irritant chemicals.