“I found this worm wriggling in my clean toilet bowl”, states this reader about the darkly-colored organism pictured below. “It is about 6-inches long, brown, with thin rounded ends, but appears to have a flat body. What is it, please?” The photo she provides does not lend us much detail: when zooming in, the organism becomes merely blurry, which speaks to the low resolution of the photo. That always makes it harder to identify an organism, as its physical characteristics are the number one giveaway for its species. That said, based on the description our reader gave us, we would conclude that this is some type of flatworm.