What on earth are these?!

[WheatToast]

They look like limpets or chitons the size of pinheads, attached to my refugium’s glass pane, but they jitter and have pulsating appendages like isopods. What do you guys think?

Below: location of pulsating appendages, circled in red.

 

[sixty_reefer]

Could be a isopod, hard to see

 

[WheatToast]

Could be a isopod, hard to see

Sorry, those are the best photos my phone can take. Perhaps I should use a different camera.

 

[sixty_reefer]

Try and google abalone snail? Might be similar to what you got also

 

[WheatToast]

Try and google abalone snail? Might be similar to what you got also

Similar, but the abalone has a “foot” rather than appendages on its underside (though it has countless tentacles on its flanks). Oh, I also love eating the larger varieties ;Drool!

 

[WheatToast]

I also just added a size reference in the original post (pinhead sized).

 

[ahiggins]

Have you searched chiton yet? I think it also has a foot but doesn’t hurt to try good luck

 

[Uzidaisies]

Yes, they’re chitons. Good guys as far as I know.

 

[Uzidaisies]

Er wait, there are predatory Chitons. They have an “enlarged anterior girdle.”

 

[afrokobe]

Similar, but the abalone has a “foot” rather than appendages on its underside (though it has countless tentacles on its flanks). Oh, I also love eating the larger varieties ;Drool!

Abalones are super tasty, love them. I saw Jake Adams got some warm water ones, wonder if anyone know where to get some.... Would be cool to have one in my tank.

 

[Uzidaisies]

It could be that the appendages you are seeing are it’s gills or a reproductive organ or digestive organ or something along those lines.

 

[Uzidaisies]

Hmm… Wikipedia; “ Placiphorella, the veiled chiton, is a genus of polyplacophoran molluscs with precephalic tentacles, which are used in feeding”

 

[ahiggins]

Er wait, there are predatory Chitons. They have an “enlarged anterior girdle.”

what?! Lordy….

 

[Uzidaisies]

what?! Lordy….

Lol, I don’t know if that kind occurs in aquariums.

 

[WheatToast]

Hmm… Wikipedia; “ Placiphorella, the veiled chiton, is a genus of polyplacophoran molluscs with precephalic tentacles, which are used in feeding”

Not sure if that’s the one I’m seeing (still not sure if what I am seeing chitons as well), but it looks absolutely insane for a chiton!

 

[WheatToast]

@Isopod80

 

[Isopod80]

Definitely an isopod. Those pulsating appendages you referenced are the pleopods. (Gill structures) Uropods are also vaguely visible. I have the same variety in my tank and they are harmless. Possibly members of the Serolina genus.

 

[davidcalgary29]

Abalones are super tasty, love them. I saw Jake Adams got some warm water ones, wonder if anyone know where to get some.... Would be cool to have one in my tank.

I picked one up from the LFS a month ago. I have no idea what species of Haliotis this one is, but it is HUGE, and probably too large for my IM40. It's also nocturnal, so not visible during the day, but I'll sometimes walk past the tank after lights out and see this thing, roughly the size and shape of a green tongue, pasted against the glass. It certainly is unusual.

 

[Isopod80]

Here's a basic research journal sketch of a similar Serolina sp. for reference. Unfortunately, there aren't many legitimate images available for comparison.

 

[WheatToast]

Definitely an isopod. Those pulsating appendages you referenced are the pleopods. (Gill structures) Uropods are also vaguely visible. I have the same variety in my tank and they are harmless. Possibly members of the Serolina genus.

Thank you so much! I think this is the one!

I picked one up from the LFS a month ago. I have no idea what species of Haliotis this one is, but it is HUGE, and probably too large for my IM40. It's also nocturnal, so not visible during the day, but I'll sometimes walk past the tank after lights out and see this thing, roughly the size and shape of a green tongue, pasted against the glass. It certainly is unusual.

Sounds awesome! Could we see pictures?
I wish I could own one, but if I did, it would probably mow down all my macroalgae .