ID these snails, please

[boeingn747]

I was in mazatlan mexico and got some rock and attached to it was these snails. I guess I would like to know what kind of snail they are and If they are of a reef safe variety?
I will add that I found them in a Tide zone attactch to rock covered in a form of macro algae. I also wonder if there are two different types present. Biggest being about 1", smallest being about 1/4".
Thanks

 

[Reefer Reboot]

Pics 2,4,5&6 looks like it may be Dark Unicorn (Mexacanthina lugubris), a predatory snail.
Check this out,

https://www.inaturalist.org/taxa/292590-Mexacanthina-lugubris/browse_photos​

 

[DeniseAndy]

No idea on ID, but any snails you cannot identify I would not put in a reef with snails or especially clams.

 

[boeingn747]

Pics 2,4,5&6 looks like it may be Dark Unicorn (Mexacanthina lugubris), a predatory snail.
Check this out,

https://www.inaturalist.org/taxa/292590-Mexacanthina-lugubris/browse_photos​

They do look very similar. I will try to get a couple better pics tomorrow. If this is what they are. It says that they are very hard to keep in an aquarium. And if they are carnivores then they would likely kill my other snails. So I will probably let them go back to the ocean, where they belong if I am being honest.