Hitchhiker ID

[Dano999]

I had two of these come with an order of Zoas. I removed them but would still like to know what they are and if they are harmful.

Thanks

http://i211.photobucket.com/albums/bb74/Dano999/ID-2.jpg

[cilyjr]

zoa spidars...they are a problem

http://melevsreef.com/id/pycnogonid.html

[crvz]

bad news, hope you didnt add the colony to the tank yet. A quarentine would have been wise, as those will happily take over other zoanthid colonies in the tank.

[k.tran]

yup. zoa spiders = bad

[bubbly]

looks like a zoa spider -- def. pest

[justinl]

yeah sea spiders, or pycnogonids, are bad news. They feed primarily on cnidarians like your beloved zoos in a mosquito like fashion; by sucking the life juices out. Won't kill the colony right away as it is a parasite, likely won't reproduce in captivity (don't quote me on that), and I think they're pretty cool, but probably isn't the best thing in a reef tank.