Reticulidia halgerda from the Philippines

Thanks Mike,
The other interesting observation from your photo alongside is the bright orange sponge which seems to be partially eaten. David Brunckhorst (1993) records this species feeding on a bright orange encrusting verongid sponge of the genus Aplysina. Although its probably impossible to identify from the photo alone, this could well be the same sponge.

You might say 'what about the gray sponge in the upper photo?' Its hard to be sure from photos just what is going on, but in the upper photo the animal is fully extended and has its rhinophores out - it looks as though it going somewhere. In the bottom photo the slug is clearly stopped and seems to have its head moving around on the orange sponge. I may be wrong, but to me it indicates this animal has stopped and is at least investigating the orange sponge, if not actually eating it. Some one say this is not scientific proof, which I would agree with, but if I have a number of different records of this species photographed on the same sponge, then I think we would be silly to ignore it. As long as you make it quite clear what your evidence is, then no one is being misled.

Best wishes,
Bill Rudman