Home  |  Fishes   |   Invertebrates  |   Apps   |   Links   |   Contact

Hawaiian Polyclad Flatworms

Although not exhaustive, this is the most complete illustrated listing of Hawaii's polyclad flatworms available. Species were identified using the Newman and Cannon 2004 CD "Fabulous Flatworms" and the Bishop Museum publication Reef and Shore Fauna of Hawaii (see bottom of page). Names followed by a number, such as "Acotylean 1" are taken directly from Newman & Cannon. When a worm could not be found on the CD or in the book, a letter follows the best-guess name, as in "Acotylean A."

These pages were put together with the generous help of Cory Pittman, who supplied many photos, observations, and identifications. Cory is curator of the Sea Slugs of Hawai`i website (along with Pauline Fiene). We are sorry to report that Leslie Newman, who was of such great help to us over the years, passed away in September 2015. We understand that a 2nd edition of her book is forthcoming, this time with four additional authors.

More photos of Hawaiian polyclad flatworms are available on Scott Johnson's website and Keoki Stender's website.
See also the Turbellarian Taxonomic Database and
the World List of Turbellarian Worms

Click on one of the numbered groups below to see Hawaii worms with a similar pattern,
or browse the
alphabetical species list

1 - Solid color or evenly translucent
(a few spots OK)
2 - Solid color with marginal bands
(a few spots OK)
3 - Longitudinal stripes

4 - Streaks or lines.
5 - Spots or blotches.
6 - Papillae

7 - Mottled or speckled
8 - Mottled / speckled w marginal bands

Thanks to Scott Johnson, Pauline Fiene, Ron Holcom, Dennis McCrea, Mike Ryan, David Rolla,
Tina Owens, Bill Stohler, Ralph Turre, Andrew Cooper, and all other sharp-eyed diver/photographers whose photos appear here, and special thanks to Leslie Newman, without whose painstaking work few of these worms could ever have been identified.

The best published reference on Hawaiian marine flatworms is the chapter "Phylum Platyhelminthes" by Jean Poulter, which appears on pages 13-58 of Reef and Shore Fauna of Hawaii, Section 2 edited by Dennis M. Devaney and Lucius G. Eldredge (1987). However, many species included on this website are not discussed by Poulter, and
some species discussed by Poulter are not included here.

The best general book on polyclad flatworms for the layperson is Marine Flatworms, the World of Polyclads by Leslie Newman and Lester Cannon, published in Australia by CSIRO in 2003, and now available for Kindle. The printed book is available here:

A large number of polyclads from around the world are illustrated and described on Newman & Cannon's 2004 CD "Fabulous Flatworms," which largely duplicates, updates, and adds to the book above. However, the CD appears to be out of print and used copies are expensive. It used to be available at http://www.publish.csiro.au


Scott Johnson
's Kwajalein Underwater website

Karolle Wall's Flatworms of Maui page (additional photos of the worms in this site)

Bishop Museum list of Hawaiian flatworms (largely out of date)

Keoki Stender's Marine Life Photography website (Hawaii flatworms)

Wolfgang Seifarth's Marine Flatworms of the World

Guam Reef Life - polyclad flatworm page

Marine Biodiversity of Guam and Mariana Islands - polyclad flatworm page

South-West Indian Ocean Flatworm site
Discover Life has detailed information on many flatworms. Use the search function to find species.

This page last revised 03/15/23

  Home  |  Fishes   |   Invertebrates  |   Apps   |   Links   |   Contact