Are these good guys? Hitchhikers

[The Mushroom Man]

Must of came on a recent addition even though i dip all my corals, but a few weeks ago i saw what looked like 2-4 little white specks, long story short then there was 100, I’ve identified them as limpets. I don’t have much experience with them i had 2 a few years back but i think they were a different breed they were large brownish tan with stripes these are all white with little holes on top, then i saw another little guy who wasn’t in there before, im familiar with collonista snails but just want to make sure it’s that and not the dreaded sundial! Ill attach some pics

 

[fishguy242]

1st pic looks like a chiton explosion ,normally good ,but may want to control population ?
@ISpeakForTheSeas ?

 

[ISpeakForTheSeas]

1st pic looks like a chiton explosion ,normally good ,but may want to control population ?
@ISpeakForTheSeas ?

It does look similar to chitons, but if you zoom in you can see they have peaked, unsegmented shells - so I agree with the limpet ID.

The snail is harmless/beneficial, but here are some ways you can tell if you've got a sundial snail:

the operculum is still a bit blurry, but it looks like the typical "stacked circles" shape I'm used to with Sundials.

Sundial snails prey on cnidarians like corals and anemones, but they do look fairly similar to Colloniid snails (and some others from the Trochoidea superfamily). That said, aside from their operculums which are a highly distinctive feature (the "horn"/"cone"/"rattlesnake rattle" shaped thing they close the entrance to their shells with - see the links below for examples), these are some other ways to differentiate them:

Also, for what it's worth, sundial snails (taxonomic family Architectonicidae) -even the more plain ones - are typically very, very ornate with their shell color, color pattern, shape, texture, etc. Many of them also basically have a flat, disk-like shell, and the ones that don't typically have shells that go basically straight up with their heads tucked in pretty far under their shells (so it'd be hard to see their heads/where their heads are popping out at under the shell in pics like the ones you've got above - with your snails, you can see the head pretty clearly despite it not sticking out very far at all). These are generalizations and probably don't hold true in all cases, but it's what I've seen across probably a few dozen species so far.

Sundial snails (Architectonicidae) on Singapore shores

Fact sheet with photos on flora and fauna of Singapore's intertidal shores

www.wildsingapore.com

Sundial Snails - tiny predators - Reef Central Online Community

Sundial Snails - tiny predators Reef Discussion

reefcentral.com

 

[fishguy242]

It does look similar to chitons, but if you zoom in you can see they have peaked, unsegmented shells - so I agree with the limpet ID.

The snail is harmless/beneficial, but here are some ways you can tell if you've got a sundial snail:

Yeah ,sorry got the two mixed up, i know that...

 

[ISpeakForTheSeas]

Yeah ,sorry got the two mixed up, i know that...

Haha, no worries - happens to all of us.