Thysanozoon tentaculatum (Pease, 1860)
"Hawaiian Knobby Flatworm"
top 3 photos: Cory Pittman (for details see captions)

ID from Reef and Shore Fauna of Hawaii, Section 2, p. 49. "This endemic polyclad has been found under rocks in the littoral zone, usually in areas of mild to moderate wave action." Cory Pittman notes that it is perhaps the most common papillate flatworm on Maui.

Newman & Cannon's CD calls this worm "Acanthozoon or Thysanozoon sp. 11" and Cory Pittman's photo below is the primary photo for the species.

Description from the CD: "Body translucent, white-cream with white dots. Dorsal papillae light brown, scattered. Margin composed of red with white dots." The CD goes on to state that the species is known only from Australia (Victoria) and Hawai`i.

Hawaiian specimens vary from whitish to golden brown (usually the latter) and the marginal pseudotentacles are edged with white.

Because T. tentaculatum was described from Hawaiian specimens we choose Poulter's identification in the book Reef and Shore Fauna of Hawaii over Newman & Cannon's ID. It is quite possible that Newman & Cannon were unaware of the species account referenced in Reef and Shore Fauna. Their color description, however, matches it and it is also quite possible that the same species occurs in Australia.

More photos can be found on Keoki Stender's website:

BACK to papillae

juveniles - Puako, Hawai'i. 15 ft.