Pseudoceros paralaticlavus Newman & Cannon 1994
"Gold Rim Flatworm"

top photo: Scott Johnson, Magic Island, O`ahu.
middle photo: specimen from Oahu sent to Leslie Newman.
bottom photo: Cory Pittman, Kapalua Bay, Maui.

ID from Newman & Cannon CD, where the top photo, taken by Scott Johnson in Hawai`i, is included. In 1995 I sent the specimen illustrated at center to Leslie Newman, who identified it as P. paralaticlavus.

Color description from CD: "Background body colour black with wide cream-white median stripe. Marginal band wide, white: rim narrow, bright yellow."

Note that Jebb's Flatworm (Pseudoceros jebborum) has a very similar color pattern. Separating the two species visually can be difficult. An entire web page is devoted to this topic.

Cory Pittman suggests that the central pale band in both species may be facultatively covered by caramel-colored mucus, and that this color, often associated with jebborum, is probably not a good character for separating the two. He offers the following tentative clarification: in paralaticlavus the central band is narrow, about 1/4 to 1/3 the worm's width, measured when it is crawling. In jebborum the central band is wider, about 1/2 to 3/4 of the worm's width, measured when it is crawling. **see below

Size might be another character: according to Newman & Cannon jebborum grows longer than paralaticlavus: 2.75 in. (70 mm) vs. 2 in. (50 mm) respectively.

The issue of whether P. paralaticlavus is just another color form of P. jebborum, was examined in a 1996 paper by Coggin and Newman, which showed a 6% difference between the DNA of allopatric specimens.

Pseudoceros paralaticlavus is known from Reunion Island in the Western Pacific to Hawai`i..

More photos of Pseudoceros paralaticlavus from Hawaii, some with pigmented central bands, can be seen on Keoki Stender's website.

cf. Euryleptid 3 is quite similar and could be confused with this species.

BACK to longitudinal stripes


Newman & Cannon include this photo on their CD as Pseudoceros paralaticlavus.

Specimen sent to Leslie Newman in 1995, identified as Pseudoceros paralaticlavus.

pigmented specimen
Cory Pittman, Maui


** complete comparison:

Pseudoceros paralaticlavus: "Central band about 1/4 to 1/3 animal's width when crawling; pigment, when present, confined to central band and light orange-brown in hue; pigmented mucus shed in relatively large, random patches; continuous marginal yellow line present; lighter line in middle of central band usually (but not always) present."

Pseudoceros jebborum: "Central band 1/2 to 3/4 animal's width when crawling; pigment, when present, confined to central band and medium orange-brown in hue; pigmented mucus lost in longitudinal strips; continuous marginal yellow line present; lighter line in middle of central band seldom present."


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