Hawaiian Knobby Flatworm, Thysanozoon tentaculatum

 

An inconspicuous, very common flatworm that reveals itself to be quite stunning on close examination. In the field, their brilliant pink and white margin and gold-spotted papillae aren’t quite as noticeable as when seen through the microscopic lens of a camera.  John Hoover’s Flatworm page provides some more photos and detailed taxonomic history. The images below are of a juvenile Thysanozoon tentaculum (we’re pretty sure). From one angle, its papillae take on a spindle-like shape, but this is likely just due to the perspective provided by the camera.