What the heck is this (ID please)

[Plankt0s]

This is a 2.5 gallon that has been set up for about a year. I have seen this a couple of times but have never been able to get a pic of it. There has been absoulutly no missing zoas or anything else everything has done great and nothing has been added to the tank for quite a wile. I am sure that it is reef safe but not sure what it is, I have flatworms and am kinda hoping that it is a headshield slug.

 

[greenbean36191]

It's Scutus, a shield limpet. It's mostly harmless but may nip at things like sponges and even some soft corals like Xenia.

 

[Plankt0s]

wow, spot on! the pics that I have found when I look up Scutus all have black antenna but im sure that this one is still just that, a Scutus. thanks. I kinda wish he at flatworms.