Acro Eating Limpets

[happyhourhero]

I wanted to post this for some visibility as I do not believe it’s too well known that certain limpets will eat acros. I believe they are sourced from the gulf. I have only had them in my last 2 builds (started in my 25 > upgraded to 150 and transferred rock) and I have had multiple orders of gulf live rock.

I have actively seen them eating the acros in both systems. They are 1/2” or so when they start eating the acros. Symptoms of limpet damage are tissue stripped but not quite all the way. If you look close and still have polyps but the color is 90% gone and maybe speckled looking, you may have them. You have to hunt them once the lights have been off for a while as they hide during the day. They blend in very, very well and I usually stab them through the hole in the top of their shell and then let the crabs eat them.

I’ll update with a pic if I find any more.

I forgot these were an issue and constantly had recession in some of my colonies on this build and kept thinking it was chem related and just could never get ahead of it. Last week, I wanted to see my cucumber stretched out so I got out the flashlight and then saw 2 of them crawling on one of my colonies and started hunting them and have killed 9 large ones so far. I will add that they really have favorite acros and won’t touch some of them.

 

[ISpeakForTheSeas]

I usually stab them through the hole in the top of their shell

Just to clarify this - there are multiple kinds of snails referred to as limpets (with a hole in the top of the shell, these are Keyhole Limpets):

True limpets are from the taxonomic subclass Patellogastropoda, and they're harmless/beneficial herbivores.

Keyhole limpets are fissurellid snails from the subclass Vetigastropoda; a handful of these snails from the taxonomic subfamilies Diodorinae and Emarginulinae are known to eat SPS:

t’s rare, but there are two taxonomic subfamilies of keyhole limpets (Diodorinae and Emarginulinae) that I have found research on showing that they have a handful of species in them that are either known to or thought to occasionally eat corals (I’d need to go digging through the papers again, but, IIRC, they only ate SPS , and they had pretty specific tastes/preferences).

just to reinforce, regular limpets are fine, and most keyhole limpets (including most from the subfamilies listed above) are reef safe; to the best of current scientific knowledge, only a very small number of them are not.

The good news is that most keyhole limpets are also harmless/beneficial herbivores, and telling keyhole limpets apart from normal limpets is generally pretty easy:

If it has a little "keyhole" or bullet hole looking hole on the back of it's shell (where the shell comes to a point) then it's a keyhole limpet.

true limpets (taxonomic subclass Patellogastropoda) don't have a hole on top of their shell at all, but keyhole limpets (taxonomic subclass Vetigastropoda, order Lepetellida, superfamily Fissurelloidea) all have one for respiration.

For some examples of true limpets:

Variegated Limpet

This is one of those spottings that made me smile, because this cluster of limpets looked like a town meeting, and it's something I'd never observed before. Cellana tramoserica, commonly known as

www.projectnoah.org

Limpets

Limpets

australian.museum

Patellogastropoda - Wikipedia

en.wikipedia.org

Some keyhole limpets to compare with the true limpets in the quote above:

 

[happyhourhero]

Thank you for the clarification on the taxonomic subclasses of “limpets”!

 

[UMALUM]

Here's a Caribbean specimen that didn't discriminate on his consumption of coral.

 

[ISpeakForTheSeas]

Here's a Caribbean specimen that didn't discriminate on his consumption of coral.

What specific corals did it eat?

 

[UMALUM]

What specific corals did it eat?

You name it...
Zoa’s were the first to start disappearing. Then a large pectinia colony. Next was a birdnest colony. This was all happening on only one large rock in the system and driving me nuts. Finally baited the rock with a Monti and busted him at 3 am.

 

[ISpeakForTheSeas]

You name it...
Zoa’s were the first to start disappearing. Then a large pectinia colony. Next was a birdnest colony. This was all happening on only one large rock in the system and driving me nuts. Finally baited the rock with a Monti and busted him at 3 am.

Sorry for your losses - on the bright side, this is good documentation to have (especially if we can figure out the ID on your species of Keyhole Limpet there).

 

[happyhourhero]

Here's a Caribbean specimen that didn't discriminate on his consumption of coral.

Mine looked very much like this. Hunted last night and only got one so maybe I am getting ahead of the adults at least.

 

[Reefkeepers Archive]

Yikes, they sound as bad as sea spiders. Thanks for giving me my warning to not get gulf rock

With my luck, I'd somehow get worse than this lol

 

[jda]

I don't even know how you got those out. Their hold can be stronger than epoxy, it seems.

I have had some that looked similar to that (no keyhole) over an inch and they ate nothing but algae. Who knows if they were the same, or not.

 

[GlassMunky]

Here's a Caribbean specimen that didn't discriminate on his consumption of coral.

This looks exactly like one that i found chomping down on one of my blasto colonies last week!! Also liverock from the gulf. at first i thought it was just sitting next to/on the coral and trhe coral was closed but then 2 days later he was still in the same spot but now it was visable multiple heads were eaten. I ended up ripping him in half by accident trying to rip him off the colony. i was holding it with forceps and then the whole shell ripped up but the soft part stayed on the coral. I was then easily able to pull the soft part off with a skewer.

Im keeping a CLOSE EYE on all limpets in the tank now, and the first sign of them on a coral they are getting ripped out

Yikes, they sound as bad as sea spiders. Thanks for giving me my warning to not get gulf rock

With my luck, I'd somehow get worse than this lol

not anywhere close to as bad as spiders, these are easy to see and kill. Id say that by far the benefits of any live rock even that from the gulf is better than any dry rock start by leagues. I got like 5 mantis, an octopus, a couple pistol shrimps, a cirinoid isopod, and still this tank is better off than any dry start i've ever done.
Don't fear the live rock.

You should have seen some the critters we used to get back in the early 2000's in live rock.... I remember looking through a bin of recently imported rock to find a whole moray eel the staff didn't know about that made it through.

 

[GlassMunky]

Heres the damage they did to my Blastos

 

[happyhourhero]

I don't even know how you got those out. Their hold can be stronger than epoxy, it seems.

I have had some that looked similar to that (no keyhole) over an inch and they ate nothing but algae. Who knows if they were the same, or not.

I have a long and skinny fillet knife that I use through the keyhole and then give it a twist. I let the crabs take over after that.

 

[UMALUM]

Just to be clear. The tank was started with KP. If I'm not mistaken Phillip drops his rock in the straits.

 

[GlassMunky]

Just to be clear. The tank was started with KP. If I'm not mistaken Phillip drops his rock in the straits.

Mine came from TBS

 

[happyhourhero]

I’ve never purchased from KP but I think all the gulf rock places are using the same lease.