Sundial Snails?

[Zakary2003]

Found two of these guys right next to a new zoa frag. They might have survived the initial dip with DipX and peroxide. I know they are tiny and an ID might be difficult but I'd still appreciate the help!

Are they sundial snails?
There are currently astrea snails in the tank. I have recently also had trochus snails (within the last 30 days) but they died. I have had mexican turbo snails as recently as 4 months ago but do not have any now. I've removed these two from the tank but there could be others. They were on top of each other and may have been mating, but they are so small it could have been coincidence.

 

[Zakary2003]

Here are some more pictures of them in the water. They can flip themselves over like trochus snails.

 

[cngh]

Imo, they are collonista snails. If so, they are reef safe, good grazers for those tiny nooks and crannies. They can reproduce easily in your tank if conditions are right.

 

[Zakary2003]

Imo, they are collonista snails. If so, they are reef safe, good grazers for those tiny nooks and crannies. They can reproduce easily in your tank if conditions are right.

Cool. Where did they come from?

 

[cngh]

Cool. Where did they come from?

Probably the new frag, or some other recent addition. Or maybe they've been there the whole time and just never noticed

 

[Zakary2003]

Probably the new frag, or some other recent addition. Or maybe they've been there the whole time and just never noticed

I'd be shocked if they've been here for any length of time. I very recently did an entire tank deep clean to get rid of a hair algae explosion from a tanksitter overfeeding while I was on vacation and there were no tiny snails then.

 

[Reefkeepers Archive]

Agree with collostonia snails, harmless/beneficial though reproduce quickly

 

[EeyoreIsMySpiritAnimal]

Not sure what they are but I've never seen collonistas that look like that...

 

[EeyoreIsMySpiritAnimal]

Not sure what they are but I've never seen collonistas that look like that...

Are the shells clear? White?

 

[tbrown]

Are the shells clear? White?

Mine are clearish white when they young. The first ones I found had almost no color at all. Eventually they gained color and became that normal brownish red.

 

[Reefkeepers Archive]

Mine are clearish white when they young. The first ones I found had almost no color at all. Eventually they gained color and became that normal brownish red.

I've never seen a red/brown collostonia snail, only white/translucent

 

[tbrown]

I've never seen a red/brown collostonia snail, only white/translucent

Not my picture:

Mine look like the darker ones here.

 

[FreeEnergy]

Imo, they are collonista snails. If so, they are reef safe, good grazers for those tiny nooks and crannies. They can reproduce easily in your tank if conditions are right.

True

 

[ISpeakForTheSeas]

Yeah, these look like some kind of Colloniid snails (taxonomic family Colloniidae; Collonista snails and relatives - algae eaters):

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:

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