Urchin ID Please

[flatfish]

I have had this tank for about a year. I saw this Urchin last night for the first time. I was quite surprised. Then I wondered if it should even be in there at all. It must have come on the LR and being that it’s about 2 in. in circumference, I am amazed that it hid so well for so long.
If you could have a look and tell me a bit about this guy I be grateful.
<a href="http://home.bendcable.com/sadony/mystery_urchin.htm" target="_blank">See him here.</a>
Thanks all!

 

[lordofthereef]

CAN'T REALLY TELL SINCE THE GRAFICS SUCK ON MY COMPUTER (MY COMPANY IS PRETTY CHEAP), BUT IT LOOKS LIKE IT MIGHT BE A PENCIL URCHIN. ANYWAY, GET RID OF IT, IT WILL ONLY GIVE YOU PROBLEMS IN THE LONG RUN.

 

[big dave]

It looks like a Stomopneustes Variolaris to me. I have a similar urchin, Parasalenia Gratiosa. Both are totaly harmless algae eaters. The only negative is they also munch on coralline algae as do all urchins. This is why I took him out of my 10 gallon which does'nt have good coralline growth to begin with, and put him in the refugium for my 29. Other than that, no special requirements. I have never purposely fed mine.

 

[flatfish]

Thanks all for the replies. I finally got a positive ID. It's a Echinometra viridis. Here's a good on-line pic: <a href="http://www.nhm.ac.uk/palaeontology/echinoids/GENERA/ECHINOID/EMETRA5.HTM" target="_blank">click here.</a>
Thanks!