Was doing a little work on the tanks this weekend and came across a couple of surprises.
First, I discovered a teeny-tiny fry in Katy's tank - the only possible explanation being that her glow-light tetras were VERY happy with their new digs when we transferred them a couple of weeks ago (none of the other species have been in there long enough to claim this little guy) - he's barely past the "wriggler" stage and has only just gotten to free swimming, judging by his size, and proved too tiny to get a picture of. He is also very quick and nervous (explains how he has managed to survive thus far ), so no removing him to a nursery - he's going to have to rely on the same luck that has carried him this far getting him past the "snack sized" stage.
To try to give the little one the best chances, I decided to move some more plants from my tank to Katy's tank to provide as much cover as possible. I pulled up a bunch of val plants and was swishing off the roots to get all the sand out of them when I discovered.........
I have crabs!!!!

This came as quite a shock since I have not purchased or added any such creature to the tank, which was set up completely from scratch within the last several months The only possible explanation I have come up with is that he (she?) must have hitchiked in on some recently purchased plants which were purchased as "potted" and left that way for a couple of days while I decided where I was going to place them - giving the little guy a chance to climb out of the plant, unnoticed, and dig himself down into the roots of the plants I was now moving. Poor thing is in rough shape - has just one leg on each side and one claw, but that doesn't seem to slow him down because he scurried down under the rocks (where the pic was snapped) and then totally disappeared moments later.

Unfortunately, from what I saw I believe it to be one of the semi-aquatic species, so I will have to track down and remove it as it is not meant to live in a setting like my tank long term - in the meantime I have left the water level down slightly so as to expose a couple of high points on my driftwood to allow someplace for it to get out of the water as needed.