Some kind of snail? I think?

[Ryderrr]

Anyone tell what type of snail this is

 

[fishguy242]

Sundial i believe , invasive if correct , @ISpeakForTheSeas ?

 

[ISpeakForTheSeas]

Looks like it's probably a Collonista or relative (though the pic is a bit blurry to say for sure) - harmless/beneficial herbivores.

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

 

[Ryderrr]

Thanks guys, I ended up pulling it out just to be safe