FLATWORM

This worm-like creatur is a terrestrial polyclad flatworm (possibly Geoplana sp.) Flatworms are simple invertebrates; the simplest of the worm groups. There are about 20,000 flatworm species in this group. Species are free living or parasitic. One well-known flatworms is the tapeworm. Flatworms are found in marine and fresh water.
I thank Mark E. Siddall, Associate Curator, Division of Invertebrate Zoology at the American Museum of Natural History for assistance with this identification.