Hypselodoris maridadilus from South Africa

May 12, 2001
From: Valda Fraser

Dear Bill
Could you identify this animals please? The upper photo taken by Dennis King shows the rhinophores clearly. I would say that they are not tipped with white and the animal is therefore Hypselodoris centunculus. Would you agree?

Both photos are from Sodwana, north coast KwaZulu-Natal, SOUTH AFRICA.
UPPER: 15m depth, July 2000, 40mm long.
Photo: Dennis King
LOWER: 18m depth, Nov 2000, 35mm long.

Valda Fraser


Fraser, V., 2001 (May 12) Hypselodoris maridadilus from South Africa. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/4307

Dear Valda,
In my opinion both these animals are Hypselodoris maridadilus which I described from Tanzania. The main external difference between it and the western Pacific species Hypselodoris whitei is that the gills and rhinophores are a uniform translucent orange or orange-red in H. maridadilus while in H. whitei they are both tipped with white. Yonow (1994) described a species from the Maldives, H. centunculus, which differs in having a whitish tip to the rhinophores but not the gills. Erwin Koehler's photo from the Maldives, which I have tentatively identified as H. maridadilus is identical in colour to the photo published by Yonow of H. centunculus.

At this stage I cannot say whether H. centunculus is a distinct species. If you look carefully at the rhinophores of H. maridadilus the tip sometimes apears to be very pale, obviously because the skin pigment is much more transparent when there is no layer of tissue behind it. What I can't tell from the photos of H. centunculus is whether the white tips of the rhinophores are caused by a white pigment or whether some trick of the light is making the translucent tips appear pigmented white.

•Yonow, N. (1994) Opisthobranchs from the Maldive Islands, including descriptions of seven new species (Mollusca: Gastropoda). Revue fr. Aquariol., 20(4): 97-130.

Best wishes,
Bill Rudman.

Rudman, W.B., 2001 (May 12). Comment on Hypselodoris maridadilus from South Africa by Valda Fraser. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/4307

Related messages

  1. Hypselodoris maridadilus in Gulf of Oman, UAE
    From: Yahia Mokhtar, July 23, 2008
  2. Spawn of Hypselodoris maridadilus: Reunion Island
    From: Philibert Bidgrain, December 1, 2006
  3. Hypselodoris maridadilus from Sth Africa
    From: David Holloway, April 1, 2006
  4. Hypselodoris maridadilus from the Red Sea
    From: Ilan Ben Tov, February 17, 2004
  5. Hypselodoris maridadilus from Mauritius
    From: Erwin Koehler, June 25, 1999
  6. Re: Hypselodoris maridadilus and H. whitei
    From: Michael Miller, March 3, 1999
  7. Hypselodoris maridadilus & H. mouaci etc.
    From: Clay Bryce, March 1, 1999

Show factsheet and all related messages