Hypselodoris zebra - old reference and new photo

Dear Thad,

Thanks for the photo. From other photos I have seen, it looks as though this species loses the white band around the edge of the mantle at it grows larger. Your colour form has many similarities to the west Atlantic form of H. picta.

I referred to Tom Thompson's paper in an earlier message [#622]. We can only hope that someone will consider the reproductive biology of the west Atlantic chromodorids to be worthy of study sometimes soon. Although some direct developers and lecithotrophic developers have restricted geographical distributions there are always examples which break the rules. As far as the local clustering you describe, I suspect this is in response to the presence of their preferred food sponge(s). Since veliger larvae settle and metamorphose on their food sponges, and the eggs of direct developers are usually laid on or near their food sponges, this sems to be the most likely cause of clustering, which is found in species of all development types.

Which brings me to the close-up I have included alongside. I am intersted in accumulating more data on the feeding specificity of the chromodorids so I always look carefully at photos for signs of potential food sponges. Most species of Hypselodoris feed on dysideid sponges. I am not sure if their is a ravaged dysideid colony in your photo or not. If you can see more in the original photo or have another photo which shows signs of such a sponge I would very much like a higher resolution scan to add to the Forum as a possibe feeding record.

Best wishes,
Bill Rudman