Unidentified shrimp in my tank! ID help
About 2 weeks ago I found this shrimp in my tank and I have no idea what it could be. Any help would be appreciated, as it doesn't look like any other shrimp I've come across.
The shrimp looks most like a Tiger or ghost shrimp. It has a brown/clear tint to it, and has alternating stripes of dark and light brown over it. It's clearly a dwarf shrimp, just nothing like any other shrimp I've seen. The colors are too distinct for a ghost shrimp (not to mention I don't have any) and the stripes are not the same as a tiger, they're more on the top than the sides. It's a juvenile shrimp, not quite an adult, but looks to have lived for a while. I'll see if I can't get some better pictures of him. Behavior wise he acts like the other shrimp, just hard to see on the wood or akadama since he blends in so well.
I set the tank up at the end of August 2012, and added in 11 Blue Rili and 9 CRS at the end of September 2012. The CRS first gave birth about 1/10/13, and the Blue Rili about a week afterwards. About 10 days after they gave birth I noticed this shrimp. I never saw a pregnant Rili or CRS in the tanks before then. The first time any shrimp gave birth in the tank was about a month ago, and the unidentified shrimp is much older than that. However, it's also much smaller than the fully grown adult shrimp in the tank.
Color wise it looks nothing like a rili or a crystal red. Size wise nothing that size should exist in the tank, they should all have been there either 4+ months or about 1 month - nothing in between. I can't figure out where or when this little guy came from, and hence I don't know what to do with him.
In other, separate tanks, I have red rili, OEBT, CBS, Taiwan Bees, Orange, Yellow, and Red Neos, and Crystal Blues. The only tank that anything could have crossed from is the Red Rili tank. When establishing this tank in August 2012 I moved some plants from that tank into this one. Besides that nothing from any of the other tanks should be in this one.
I'm confident this fellow wasn't added to the tank when I started it up. I can still count all 11 blue Rili. I only have 5 CRS left because a few died. I'm also fairly confident that none of the Rili or CRS gave birth before 1/10/13. This little guy looks like he would have been born around November based on the size of him and other babies I have that in other tanks.
Any help would be appreciated. I don't know whether to cull this little guy or give him special treatment. I'll try and lure him out to get some better photos as well.