Trochus snail with sensory tentacles ON shell?

[Kontactk]

Hi all,

 

One of my trochus snails looks like it has additional sensory tentacles. It has the normal ones that come out around the base of the foot, but it also has a bunch that are all over the top of the shell, even growing throughout the spiraled part and some near the top. At first I thought it was algae, but they wave back and forth JUST like the tentacles. Has anyone else seen one like this before?

 

 

 

 

 

 

 

 

 

 

 

[kinetic]

Definitely algae or some other critters. Not snail.

[Kontactk]

Here's a video. ID anyone?

 

 

[Kontactk]

Now that Im looking at it more closely, the little tentacles appear as pairs on the snail's shell..

[xiaoxiy]

12 hours ago, Kontactk said:

Now that Im looking at it more closely, the little tentacles appear as pairs on the snail's shell..

Your snail has some hitchhikers that have made their home its shell!

[Oldsalt01]

I recently found the same thing living in the back of one of my rocks. With the flow off they wave around like there's current. Hope someone can ID them as I have no idea. The position of the rock makes it impossible to get a good look at the critters.