Found a starfish.. Asterina?

[Stephany]

I got some really nice Indonesian rock a few weeks ago... and today there was a starfish on my powerhead? I've read that asterina are typically found, but I was wondering if I could get confirmation?

 

[Jedistphn]

YUP!

 

[dalbrecht]

Definately Asterina

 

[friendlyAlien]

I found some of those lately .. are they bad or good?

 

[Stephany]

Thanks guys. I also found something else this morning on my live rock. It is about 1.5" long, and has a flat shape top to it. It has a smooth back, with two short lines of "spikes" that stick up on it.... Here's a pic. After I turned the light on, it started to move (like a snail) under the rock away from the light. The object is dead center in the picture.

 

[dalbrecht]

It's almost impossible to make out anything in that picture. It's a bit like taking a Rorshach test. But I see what could be a bristleworm (white spines on a ruddy body)

 

[Stephany]

I know... it's bad. The shape of its body was like a cockroach though. Oval, and flat... although it wasn't ridged or divided up.

 

[becon776]

yeah... i wouldn't make a habit of touching unidentified objects with spikes in your tank ;-) esp. not bristleworms... I'm speaking from experience here.

 

[Kent E]

Please take another picture.

 

[Stephany]

I'll try again after the lights go out tonight.

 

[Stephany]

It's not on the underside of the rock that it was hiding anymore. I don't know where it is anymore... =/
It's like a cockroach, oval shaped brown... but with a snail-type base. And there are two rows of even length/spacing spines down the middle off its sides. As in, the unspined shell is "divided" into equal thirds based no where the spines are.

I'm guessing they're not common... I haven't seen any pictures of them before...

 

[puter]

Hi Stephany -

I can't tell anything from your picture, but as a WAG do a search/image search for info about chitons.

- Mark

 

[Stephany]

I came up with a lot of images...
http://www.timespub.tc/Natural History/Archive/Summer2000/chitons.htm
http://en.wikipedia.org/wiki/Chiton
From what I've gathered:
They stay on rocks, to protect their soft underside.
They're real hard to get off the rock, unless you've got a thin sharp knife, and practice.
It says here that they eat algae (coralline...?!?), seaweed, debris, dead stuff...
I saw a picture of one that caught a crab (but I read that is a kind with an elongated head...)
I am almost positive mine doesn't have an elongated head.
They are nocturnal.
They are intertidal animals.
I'm quite positive that's what I have. Thank you for the hint...!
Anyone else have them in their tank?

 

[moriartiholmes]

There's a small one that is common on live rock, I have a bunch of those in my tank. Some of the larger ones are cool; just make sure you find out what yours eats. I think some eat soft corals etc.

 

[St.james of reefdom]

Do the Asterina s eat hard corals like Montipora digitat or other acros... I have had a Monti with purple tips over the last week turning white but in blotches when I broke off the piece it had several mutant asterinas ,most with 3 legs or two legs...How can I get rid of the asterina?

 

[moriartiholmes]

Some of the species do. Those arenââ"šÂ¬Ã¢"žÂ¢t mutants they primarily reproduce by fission. The six arm one in the top pic may be two three arm ones right now for example. If they are causing a problem in your tank, you might have to add an echinoderm predator, since your system volume would make it difficult to hand remove all of them.

They say that only certain species eat SPS and other corals. I had one go after a zoo once, that star had to have been in the tank for months (due to when the last addition was). This was the only time I had one go after a coral. It seemed to me that the star went for the coral because it was not finding enough algae to eat.