Nasty Snail Eating Predator - Pictures!

-Logzor · Sep 5, 2011

Finally caught this bugger!!

This thing has been lurking around my reef for quite some time now. I assume it is some kind of flatworm. I've seen this thing completely smother large turbo snails, slurping up their soft bodies.

Needless to say I haven't dared to buy any new snails!

Last night I went down into the basement to see if the cat was hiding down there on my office chair and I saw this thing on the front glass, smothering a poor little strombus grazer (these snails naturally repopulate in my reef). The lights in the tank were off, this flatworm is very sensitive to light and was already trying to run away when flipped on the lights.

Luckily I had a cut-off 20oz coke bottle laying right there so I just scooped it off of the glass.

Here are the pictures, this is the bottom half of a normal 20oz coke bottle, for size reference.

nixer · Sep 5, 2011

wow thats a monster!

toyencounters · Sep 5, 2011

I cought one just like it by accident late at night about 2 weeks ago it was very fast I was suprised. I could not figure out what it was???

-Logzor · Sep 5, 2011

toyencounters said:
I cought one just like it by accident late at night about 2 weeks ago it was very fast I was suprised. I could not figure out what it was???

Indeed, they are very fast movers, I could have never caught it unless it was on the glass. I tried to catch it once before and this creature kind of falls apart when you handle it roughly (scraping it off of a rock). This time I got the entire thing.

toyencounters · Sep 5, 2011

You are right when I ran to get my long tweezers I thought it was a done deal! When I grabbed it I only got the body beacuse it cut off without me putting a lot of pressure and the head ran off superfast into a rock. I could not get the entire thing the head is in hidding somewhere in my rocks. I am looking for it every night!

toyencounters · Sep 5, 2011

Is there a name for it??

toyencounters · Sep 5, 2011

At first I thought it was some sort of shrimp?

Alpha Aquaculture · Sep 5, 2011

When I posted pics of this one I found I was told they eat clams. Not too hard to this they would also eat snails.

dnov99 · Sep 5, 2011

toyencounters said:
Is there a name for it??

Polyclad flatworm, they are nasty. I have come across a few of them in the past and luckily got them out...

myzislow · Sep 5, 2011

polyclad flatworm. Good thing you got it out!

toyencounters · Sep 5, 2011

What else do they eat and where do they come from?

-Logzor · Sep 5, 2011

AlphaCorals said:
When I posted pics of this one I found I was told they eat clams. Not too hard to this they would also eat snails.

That is most definitely the same creature. That's crazy it eats clams, luckily I've never had any clams for it to eat!

Alpha Aquaculture · Sep 5, 2011

toyencounters said:
What else do they eat and where do they come from?

They probably eat all types of snails and shelled softies. I would bet they get into our system via hitchhiking in the cracks of coral rocks or live rocks.

Alpha Aquaculture · Sep 5, 2011

-Logzor said:
That is most definitely the same creature. That's crazy it eats clams, luckily I've never had any clams for it to eat!

Definitely not a lettuce nudi here lol

returnofsid · Sep 5, 2011

That is a predatory Polyclad flatworm. They can get very large. Their primary "victims" are snails and clams. Luckily, unlike most flatworms, they are NOT asexual, so need at least 2, to reproduce. Over the years, I've found a handful of them, in some of my tanks.

-Logzor · Sep 5, 2011

returnofsid said:
That is a predatory Polyclad flatworm. They can get very large. Their primary "victims" are snails and clams. Luckily, unlike most flatworms, they are NOT asexual, so need at least 2, to reproduce. Over the years, I've found a handful of them, in some of my tanks.

Very interesting, thanks for the more detailed information. Hopefully it was only the one in there! Maybe now I can actually buy some "real" snails. Love my strombus grazers but I wouldn't mind some larger snails that have more of an impact.

These things can smash themselves into tiny crevices, unlike most other pests, the hold on tight if you dip the coral/rock on which they are attached. Typically critters will scurry off when Iodine, FWE, Coral Rx hits them, definitely not the case with these things, they'll hold on to the death.