Critter ID

[ReeferFL]

I noticed this critter 3 weeks ago and has since doubled in size. Tank is only 6 months old with no corals yet.

I’m thinking some kind of isopod??? Haven’t seen anything like it though and its pretty quick too.

Any help appreciated…thanks

 

[jtp7004ft]

chiton or Sand Skater........

 

[ReeferFL]

top and underside pics. Appears to have legs and a back single tail fin. Moves very fast. Also has been rolling up in a ball when handled.

 

[ISpeakForTheSeas]

top and underside pics. Appears to have legs and a back single tail fin. Moves very fast. Also has been rolling up in a ball when handled.

Isopod - if it's rolling into a ball, it's likely a Sphaeromatid isopod, and it should be harmless/beneficial.

 

[ReeferFL]

Isopod - if it's rolling into a ball, it's likely a Sphaeromatid isopod, and it should be harmless/beneficial.

After looking at the underside, I believe so. I’ve just never seen one with markings like this…almost as if it’s wearing a tuxedo. Lol.