Photo by Bob Thomas, Asa Wright Nature Centre, Trinidad.
Bipalium flatworms are easily differentiated from Gigantea gigantea by having a spade-shaped head (see underside on left of this worm pictured). They occupy the same general habitat, and it would be interesting to study how they partition the ecological resources available to both.
This worm is a predator of small invertebrates, and uses its slime to prevent desiccation. They are pan-tropical, but also live in temperate zones, including our yards in New Orleans.