Need identification of these snails

[NemHost]

I first noticed these snails few days ago and they it seem they are everywhere. At first I thought they were collonista snails but I’m really concerned that they are actually sundial snails.

 

[Coral_North]

Pretty sure they are Trochus Snails

 

[Jose Mayo]

Collonista snail; the "sundial snail" is more flat and wider in its spirals, its surface is not smooth, like that of the Collonists and their marks are less continuous, resembling points and not lists. Another difference between them is the operculum, which in the Collonista is flat and in the "sundial snail" is conical. The major difference between the two, however, lies in the ventral face, in which the Collonist's spiral is more closed and rotates on itself, whereas that of the "sundial snail" is more open and revolves around an "imaginary axis ", leaving a hole in the middle, as in the photos below:

"Sundial snail" (Heliacus areola) ......"Turbo snail" (Collonista sp)

Regards

 

[KJ]

Look like a baby Trochus snails.

 

[NemHost]

Thanks for your replies. It certainly makes me feel better that these are not sundial snails. I know these ones are supposed to be beneficial but it does seem they irritate corals. I will be adding a coris or melanurus wrasse to keep them under control.