ID help please?

[H20Sidhe]

This is crawling on my glass today. Never seen anything like it. It seems to have tube feet, and reddish mouthparts. It is 1/4 in long by 1/8 in diameter. Since it is on glass, this is ventral surface. Dorsal surface I can sort of see by looking through the end of the tank, and it seems to be light gray-tan. It seems to be as tall as it is wide (in other words not flat). The photos were taken through my 10x lens. Anyone have any idea what this?

Thanks

 

[Nu2SW]

wow, thats really interesting.

you never know what kind of creatures you can have in your tank.

 

[Sk8r]

I think it's a pod. See: harmless grazer at
http://home2.pacific.net.ph/~sweetyummy42/hitchhikers.html

 

[Justin74]

I'd keep searching, unfortunately I dont know what it is, but It definately looks bigger and more sinister than any pods Ive seenIt's shaped like a chiton if it werent for the soft looking outer layer with tenticles.Definately a trip nonetheless, keep us posted!

-Justin

 

[Wee-Reef Master]

I'd be suspicious. I don't like the fact that it displays appearance that looks like polyps of some sort. Could be to hide amongst SPS whilst devouring them!

 

[MelodyCorals]

I'm definately no expert, but can Google fairly good , so I was thinking it looked a little like a chiton too. Is a chiton an isopod? Perhaps this is a form of isopod - which may be a not so good thing potentialy - but maybe not harmful either. Have you seen any on your fish?

Maybe this can help you identify them:
http://www.wetwebmedia.com/isopodfaqs.htm
http://www.wetwebmedia.com/isopoda.htm
http://www.reefkeeping.com/issues/2006-02/bp/index.php

-- Josh

 

[wombat2]

It's the leg of an Asterina sp. starfish.

 

[MandM]

You rock Matt! It looks like a leg off that very animal.

 

[pepe.king.prawn]

wow, interesting!

 

[MelodyCorals]

Wow... - that is totaly strange. I bet that is it though... amazing - I would have thought they needed more of their central body.

-- Josh

 

[Sk8r]

Cool! I think you've got it!
Starfish have pretty amazing powers of regeneration...but that's going some.

 

[dhnguyen]

Holy crappola I would have never thought to associate that with an Asterina star. Good eyes wombat2

 

[H20Sidhe]

Thanks Matt. That is exactly what it is! It was sure bugging me not knowing . . .

For years I've seen the little starfish wandering around with only a couple or three legs. Now I've seen the leg wandering around! It went back down into the gravel, so I may never know if it had enough body to regenerate. Do you know if they just spontaneously 'fall apart' (like a lizard will drop it's tail) or if there is something dismembering them?

 

[wombat2]

I've seen otherwise completely healthy Tamaria stria (aka 'purple linkia') do this too. One day we just found some arms that were crawling around in the refugium. They ended up living about 6 months before dying.

At the time I emailed Rob Toonen about it, and this was his reply:
"Those purple stars are usually either Tamaria stria from the Sea of Cortez or Leiaster teres from the IndoPacific - I don't know where they came from, so I can only hazard a guess at Tamaria from what I remember... Tamaria stays smaller (about 5" maximum diameter) and has more than 5 arms, whereas Leiaster has almost always got 5 arms and can get more than a foot in diameter.... Regardless of which one you have, both species are predatory on small sessile invertebrates (there have been no studies on these particular species, but all members of these two genera feed on clams, snails, sponges, tunicates and small cnidarians). To the best of my knowledge, there has also been no studies of the reproductive behavior of either species, but what you describe is very common for some species of Linckia, and could well be a form of asexual reproduction. Asterinid sea stars can go an amazingly long time without food, and can digest their inner tissues to support themselves during periods of starvation or regeneration. It is quite possible that they may be able to completely regenerate the body from a simple limb bud such as you describe, and that is actually the primary mode of reproduction for species like Linckia multifora. You can probably find some cool pics if you search for images of this species in Google..
That's great to hear - say Hi to everyone at MARS for me!
Rob"

Hope this helps.

 

[Justin74]

Sweet Matt! The picture was totally throwing me off and looked like a top view, good eye indeed! Not that I would've every come up with that answer anyway

-Justin

 

[H20Sidhe]

So much easier to identify like this!

 

[wombat2]

Only echinoderms (seastars, urchins, cucumbers, medusa worms, brittle stars, etc.) have tube feet. So that kinda gave it away right there.

 

[H20Sidhe]

I knew the tube feet narrowed it down, but I wasn't able to connect the dots beyond that point! It didn't look like a star fish, brittle star or urchin to me & I have no experience with cucumbers or medusa worms. I didn't think outside the box to consider it could be a part of an organism.

I have great respect for your experience, and/or powers of observation, or whatever it is that enabled you to figure out the answer.

Thanks!

 

[robertloop]

Sweet catch Matt.

 

[wombat2]

Thanks, and it was nice to meet you tonight!

Matt