hitch hiker?

[j-spot]

I have what appears to be 2 baby pin cushion urchins. My tank has been set up for well over 10 months and just a few days ago I noticed the 1, and today I can see another. They are about the size of a pencil eraser, but other than that look just like other pin cushions. Is it possible that there were eggs on the live rock that hatched and are finally at a size and shape that can be identified or could they be something else? I am not sure if I should just leave them be or take them out. From watching the first for a few days and today the other, they don't seem to be interested in any of my corals, just pretty much staying in the same area. When the lights come on both make their way into the shade, avoiding any bright light. So should I be concerned here or just let them be? Hopefully I don't find more but there are alot of places to hide in over 100 pounds of rock.

 

[j-spot]

Here is a couple of pics from my crappy camera if it helps. Sorry for the glare but all lights are off.

 

[alyssia]

They look like urchins to me. I have one and it has never bothered anything.

 

[ninjamini]

I have one also that came on the live rock in my 12 gallon and was too small to know was there. Now its an inch or two (depends which spines you count the hard ones or the wavy ones) and does not seem to bother anything. He's kinda cool.

 

[isistius]

i got one as a hithhiker also.....pretty cool. doesn't seem to bother anything in my tank...