Pictures of "Baby Mantis Shrimp"

[ak-dave]

I took some close-up pictures of some amphipods tonight, and I thought I'd post some of them here, since a few people have been mistaking them for mantis shrimp. Having never personally seen a live mantis shrimp, I can see where someone could make the mistake. Note how the large front leg resembles a raptorial appendage.

I have more close-up pictures of other pods in a thread in Dr. Ron's forum located here.

 

[Gonodactylus]

The littly guy with two spikes off the side of the tail is an isopod.

 

[ak-dave]

The littly guy with two spikes off the side of the tail is an isopod.

Yes. It is a sphaeromatid isopod, one of the "good guys". There are several copepods in the pictures, too. Their body is about the size of one of the spikes on the tail of the isopod. Some of them have egg clusters on their tails. In the first two pictures, there are also some baby bristle worms. I have a close-up shot of one of them in the thread referred to in my first post.

 

[Neo-Fight]

I don't doubt that your isopod is a good guy, but I had to pull one that looked very similar off a seahorse a few days ago. I suppose he could have just been being friendly, but he held on pretty good... with his mouth! After some research here on RC, it turned out that there are definitely parasitic isopods that will burrow into your fish. Be careful!

 

[ak-dave]

I don't doubt that your isopod is a good guy, but I had to pull one that looked very similar off a seahorse a few days ago. I suppose he could have just been being friendly, but he held on pretty good... with his mouth! After some research here on RC, it turned out that there are definitely parasitic isopods that will burrow into your fish. Be careful!

It was positively identified by Dr. Ron as a sphaeromatid. The tank has no vertebrates in it, so if it was a parasitic isopod, it would have starved. As it is, there are several hundred in my 10 gallon tank, ranging in size from 13 mm down to less than 1 mm. They definitely eat diatoms and algae. Any isopod you find attached to any fish will be parasitic. Some of the bad guys look a lot like my isopods.