January 17, 2007
From: Leanne & David Atkinson
We were thrilled to find both Okenia vena and Okenia purpurata again at Port Stephens yesterday. Here are some photos of Okenia vena that we discovered were mating when we looked at the photo on the computer after the dive. Since they're mating we'd assume they are adults? These were relatively small in comparison to Leanne's black-gloved finger in the 2nd photo and she only wears a small glove. We found them on their food bryozoan again looking to the naked eye like tiny flecks of broken shell.
Locality: Halifax Sponge Gardens, Marine Reserve, Port Stephens, 16 metres, New South Wales, Australia, Pacific, 13 January 2007, Sandy bottom with scattered sponges, ascidians, soft corals, and bryozoans. Length: approximately 2 to 3 mm. Photographer: Leanne & David Atkinson.
We have more photos of Okenia purpurata but they weren't doing anything exciting and we weren't sure whether to send them since you have our previous message from the same area. By the way we found it is linked to the fact sheet for Okenia purpureolineata instead of Okenia purpurata.
Leanne & David Atkinson
firstname.lastname@example.orgAtkinson, L. & D., 2007 (Jan 17) Okenia vena mating. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/19228
Dear Leanne & David,
Photos of any species we know so little about are welcome. I would certainly like some more of O. purpurata. Even getting another record of both these species occurring on the same bryozoan Amathia tortuosa is valuable, because it is the way we gradually build up our knowledge of just how specialised these species are in the food they eat. It also gives us a better idea of just how variable the colour pattern is in each species.
I have included a close-up alongside from one of your photos which shows how the row of zooids forms a spiral up the stalk of the bryozoan colony. I presume that is how this species got the name tortuosa [= twisted]. Sorry about linking your earlier message to the wrong species - I've fixed it. I try to weed out errors like this but am always grateful for any proof-reading help.