What are these?

I just noticed these guys in my tank today, probably because I hadn't scrubbed the algae off the glass in... erm.... weeks. Does anyone know what they are?


I also found this!

 

first pic looks like bubble algae, second pic looks like a porcelain crab. i think the crab is safe.

 

It's hard to say on the algae until it grows out a little more. It's likely a Caulerpa holdfast.

 

Neomeris annulata is a possibilty on the first one. Try a google image search or Wetwebmedia.com

 

Thanks, guys! The reason I was concerned about the crab is because I've got a sea apple in my tank. I suppose he's not messed with him thus far. We'll see...

 

i dont think its a porcelain crab - they typically have these fan like arms on them and yours doesnt. I would just chuck it in the sump.

 

After some Googling, I am thinking he's a Jonesius triunguiculatus or a pinnotheridae. He had molted, which was what I found. That isn't actually him, and I have NO idea where he is!

 

http://www.natuurlijkmooi.net/images/neoannc.jpg

that looks like your algae. I have a bunch of it. It's calciferous.

 

yea but your crab has fat short legs. pinnotheridae have skinny, longer legs.

 

it could also be a variety of xanthid species. if you happen to see it look for hairy legs.