Whats this? Need id

[tnmichx6]

Turned on lights on this morning and saw this sliding along the rocks. Circle and redish brown with white on the back/ top. Can anyone id this for me?

 

[mr_X]

It's a stomatella snail. A good hitch hiker.

 

[tnmichx6]

Thank you. Being a good hitchhiker, it won't harm any coral?

 

[severum mama]

No, it won't bother coral.