Baby trochus snails?

[Arcticreef]

Hi. I have 4 of these that I can see in my refugium and sump. They are approx 3mm in diameter. In my DT I have nassarius, banded trochus and cerith snails. Just wondering which one this might be. Assume it's a trochus from the shell shape (except for the protruding ridges) but could be a hitchhiker that bred?
Thanks.

 

[Goaway]

Looks like star astrae snail. Look those up and see if it matches.

 

[Arcticreef]

Thanks Mibu. You might be right. Surprisingly so few good res photos of juvenile snails out there in the interweb. Could also be a regular astrea and not a star, but guess time will tell.