November 7, 2008
From: Leanne & David Atkinson
We think we found Okenia hallucigenia at Halifax at the weekend. There were three individuals close together. They seemed longer and higher bodied than our usual Okenia atkinsonorum. The oral veil seemed much more pointed. Have we identified them correctly or are they just H. atkinsonorum stretched out?
Locality: Halifax Sponge Gardens, Port Stephens-Great Lakes Marine Park, Port Stephens, 14 metres, New South Wales, Australia, Pacific, 02 November 2008, Sandy bottom sponges, bryozoans, soft corals, hydroids and ascidians. Length: 15 mm. Photographer: Leanne & David Atkinson.
Leanne & David Atkinson
firstname.lastname@example.orgAtkinson, L. & D., 2008 (Nov 7) Okenia hallucigenia ? from Port Stephens. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/22019
Dear Leanne & David,
You are quite right. This is O. hallucigenia. I had begun to wonder what had happened to this species in the Port Stephens area, because in all your years of observing you have only photographed O. atkinsonorum. In fact we have no records on the Forum of this species from anywhere. This species is characterised externally by the strange 'oral veil' at the front of the body and the regular 4 pairs of lateral papillae down the body. It will be interesting to see if it will maintain a permanent population in the Port Stephens area or whether it is a tropical species with larvae that only rarely travel and successfully settle this far south. It would be interesting to see what sort of egg ribbon it lays.