Mystery Nudibranch

[Sascha D.]

I've seen him three days in a row. Most of the time it's on the glass. This one time it was on the rocks and I snapped a shot. I haven't seen it on any corals or polyps. My search results thus far haven't turned anything up. Any ideas?

[victoly]

looks to me like a zoa eating nudi

[FarmerTy]

I would agree.

[Timfish]

I was thinking it looked like a Brughia or aptasia eating nudi.

[Sherita]

It's either a zoa eating nudi, or a sun coral eating nudi. Definitely not burghia.

[Sascha D.]

Phestilla melanobrachia. Red Sea, East Africa to Australia, Japan, Hawai'i. To 2 cm. A good match for what Dendrophylliid coral? Feeds exclusively on Tubastrea... with matching egg masses laid on their food... of similar color. N. Sulawesi image

After looking at hundreds of pictures of hitchhiking nudibranch, I finally found a similar picture. That led me to this article on wetwebmedia. The very last entry on page 6 has a picture that is spot on. I also found a species list on The Sea Slug Forum

[FarmerTy]

The big question is, do you have any tubastrea coral then?

I would imagine that if you don't, that thing wouldn't survive another week or 2.

I would check all your zoa colonies at night when the polyps are closed just in case. I know its just a picture so hard to tell but that looks spot on with zoa eating nudibranchs that I had when I first got into the hobby. Coloration will vary depending on the zoas they are feeding on. I would imagine though that there are a ton of nudibranchs species that look exactly the same.

Sad thing is they are quite beautiful looking, especially if they are chomping on your most expensive and most beautiful zoas.

[Sascha D.]

I don't have any tubastrea coral. Some of my zoas are closed up right now, while others are thriving. None of the leathers, mushrooms or palythoa seem affected. All of the LPS are doing fine.