Crustacean ID: Predatory Isopod in the Superfamily Anthuroidea -- 5/4/10
<Hello, Lynn here today>
Well with no luck at RC, we thought you guys might know what this is http://www.reefcentral.com/forums/showthread.php?p=17050576,
http://www.reefcentral.com/forums/showthread.php?p=17050576&posted=1#post17 050576> &posted=1#post17050576
<Oh wow, I've seen these critters in photographs but never heard of one showing up as a hitchhiker. It's a predatory Isopod in the Superfamily Anthuroidea, of which there are six families and many genera. I would not return this little fellow to your system. Please see the following link for a list of families, each of which is a link to a description: http://www.environment.gov.au/biodiversity/abrs/online-resources/fauna/afd/taxa/ANTHUROIDEA/checklist#selected .
By the way, great photos! Take care, Lynn Z>

Mystery Crustacean: Sand Crab, Albunea sp. 4/10/10
<Hello, Lynn here today. First of all, I sincerely apologize for the delayed reply. The good news is that I've got an answer for you!>
I am stumped on this one. Would you please identify this mystery crustacean for me, please.
<You betcha. It appears to be what's referred to as either a 'sand' or 'mole' crab although it's not a true crab/Brachyuran at all. These neat little creatures are instead Anomurans, a group of Decapod Crustaceans that includes hermits, porcelain crabs, squat lobsters, etc. Your individual belongs in the Superfamily: Hippoidea, Family: Albuneidae, Genus: Albunea. Not a whole lot is known about these 'crabs' except that they seem to like relatively shallow waters and/or areas of the swash zone and are able to burrow backwards into the sand/silt. Of note is that they have the same feathery antennae and burrowing habits as some of their relatives so they may well feed on similar foods, in the same manner. For example, in the family Hippidae, Emerita species are suspension feeders that use their feathery antennae to filter phytoplankton from the water. One big difference though, between the genus Emerita and Albunea that has a bearing on feeding is that Emerita species don't have any sort of pincers for grasping while Albunea species have small ('subchelate') ones. Perhaps these animals filter-feed like Emerita but also grab little items as they pass by. It's also possible/likely that they do a bit of scavenging as well. Please see the following links for comparison. You didn't mention where you found your individual, or the size, so unfortunately I can't do a lot to narrow the field of species possibilities for you. Also hindering the process is a lack of available species photos.
Albunea catharinae, from the S. Atlantic: Note the same finely serrated edge at the front of the head and the shape of that outline. It also has the same hairy look about the legs and front, same antennae (feathery), and same basic anatomy otherwise (see second row, far right): http://www.dnr.sc.gov/marine/sertc/gallery.htm
Close-up: http://www.dnr.sc.gov/marine/sertc/images/photo%20gallery/Albunea.jpg
Albunea marquisiana from the Marquesas: http://decapoda.free.fr/illustration.php?n=2&sp=26
Albunea speciosa from the Society Islands (note the claws): http://decapoda.free.fr/illustration.php?n=1&sp=27
I hope this information helps! Again, sorry for the delayed response!>
Thank You
<Take care, LynnZ>

Strange Creature In Reef Tank...What Is It? 1/21/10
I found a weird creature in my fish tank last night when I was feeding the fish and corals. This thing measures about 1' long, it is like a transparent dark brown/green color similar to a bait shrimp, the head is like in a flat arrow shape, it has claws that was using to move the crushed seashells from under the rock, it has pretty long antennas for his size, I'll say about 1cm, it moves very fast, it will start crawling out very slow to try to reach some food pellets but I never got to see the full body out, I saw most of it but never got completely out of the rock. I used to have an Engineer Goby that dies and I thought it was a baby but now, this has a mixed look like a lobster+shrimp+cockroach <?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />
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I managed to take some pictures (attached) but they came a little blurry and I was only able to get the head , I circled in the image the creature so you can see it. It moves very fast when goes back inside the rocks so it took me about 10 minutes to take the picture.
What is this thing?
<Well, as you say, the pictures aren't resolved enough for an accurate ID, but by your description, I'm guessing you likely have a shrimp of some type, possibly a Pistol Shrimp or Mantis Shrimp. Are you hearing any clicking/snapping sounds?>
Thank you.
<You're welcome. James (Salty Dog)>