interesting growth on snail

[Richard Helbock]

It's a 20mm disk on a 50mm long by 1mm thick stem that looks like it's growing from the snail's shell. Any ideas? My wife thinks it might be a crinoid...

It's been in my sump fuge for a few weeks and I finally got a good look at it so now I'm curious. Please don't mind the hair algae.

 

[Peach02]

any chance you could get a closer up photo?

 

[Richard Helbock]

The snail is on the far side of the sump fuge this morning so I'll have to wait for another closer angle. Is there a particular feature you'd like more detail of? I'm thinking the point of attachment or the center of the disk with the radiating grooves might help so I'll try again. For now, I've cropped the image for detail since the raw submission was down-sampled... Pretty weird, huh?

I'd like to try and remove more hair algae from the snail so I can better see the point of attachment but the structure of the mystery growth looks fragile and I'd hate to damage it.

 

[Crabs McJones]

Acetabularua Acetabulum
Mermaid cup algae

 

[Richard Helbock]

Thanks, Crabs! I think you nailed it... but then you knew that ;-) Been watching this forum for over a year now and haven't seen any reference to this algae. Will be researching it further from here.

Thanks again and kindest regards,
Richard
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