Hitchhiker urchin ID

[witecap4u]

Is this a pencil urchin, or another type?

The pic isnt the best since I was shooting with the tank lights off
http://home.austin.rr.com/twad/urchin.JPG

T/

CSeel

[GaryP]

It could be either a pencil or miner urchin.

They are herbivores and will graze on algaes on your LR and glass. They will eat the coraline algae as well as stuff like hair algae. They can be somewhat destructive in that they can knock over the LR in your rockscape.

[Polkster13]

What did it hitch-hike in on? I am assuming it was Live Rock, but from where was the Live Rock collected? This will give us valuable information in determining exactly what you have there. I can then look through my invertabrate library and possibly come up with an ID.

[Polkster13]

It kind of looks like this:

http://www.robertosozzani.it/Rosso3/urchin07.html

[GaryP]

If that's not it, its darn close Polkster.

[tweety]

If that's what it is, is it good or bad? :unsure

[Polkster13]

Guess that depends on your definition of good or bad. It does bore into rock.

Here is some more info.

http://www.edge-of-reef.com/echinoidi/ECHEchinometramathaeien.htm
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=110587 27&dopt=Abstract
http://saltaquarium.about.com/cs/aboutjanitors/a/aa052899_4.htm
http://www.wetwebmedia.com/urchinsii.htm

There is a ton of other info on this species. Just do a Google search.

[GaryP]

Most urchins have a tendency to turn your nice pretty purple live rock into not so nice, not so pretty, white live rock. They graze on the coraline algae that's there. On the plus side they do a good job on a lot of nuisance algaes too.