Strange critter on LR

[FrostyNYC]

I just got a new piece of live rock with shrooms on and and I found THIS:

I searched the rock over and over, found one apistasia (killed it) and a lot of worms, a few pods, and I missed THAT huge thing. It was only at the last second that I saw it. It's green and black, and about 3/4 of an inch long. Its very very flat and looks to have a segmented carapace. It's moved a tiny bit in the last half hour or so. Any ideas regarding what this thing is?

 

[FrostyNYC]

Okay, I think I just ID'ed it as a chiton. However, some sites say they can leave rasp marks on acrylic tanks. Anyone have any tank damage from these guys?

 

[Dre]

I saw them in the wild only but i think your aiptasia should be dealt with ASAP.

 

[FrostyNYC]

I saw them in the wild only but i think your aiptasia should be dealt with ASAP.

I QT'ed the rock for a couple hours and only found one aptasia hiding in a crevice. I scraped it out, along with a good deal of the LR that it was anchored to. I'm keeping an eye on the rock for more. Its a small chunk of rock so I'm not overly concerned.

I've never had them in my main tank... although in my paranoia I've killed innocent featherdusters.

 

[KathyC]

Scraping out aiptasia usually results in even more aiptasia unfortunately. Any little bit you leave will grow back.
Better to use kalk paste or Joe's Juice to get rid of them.

Yes, that is a chiton. No experience with acrylic tanks & these guys. If you are concerned (any obviously have an acrylic tank) I'm sure you could easily re-home him to someone with a glass tank