Shrimp ID Help ...

So I've started a small 2.5 gallon tank to grow pods and shrimp ... I was cleaning the pods off of a filter sock yesterday and noticed about 3 tiny shrimp looking things. I picked them off too and threw them into the container. There were many sizes of pods in there also. I did notice these guys zipped around the cup extremely fast. They seem flattish and pretty uniform in size all the way from head to tail. They are a light red color. Tail seems split into 2 pieces that are overlapping. It seems to have the "nose" like a typical shrimp but I really can't tell what the arms look like, but I did see them extend somewhat a couple times. I cleaned the filter sock again today to see if I could find another to take some pics. I couldn't get it too clear because it is just so tiny ... but hopefully it's enough to make an ID.

This morning I started looking up shrimp and pods and whatever I could find that might be similar and the first thing I saw was mantis shrimp ... this had me worried and that's when I caught another to document. Anyway ... it seems flat and uniform in size like the mantis but the tail doesn't flair and the arms don't SEEM to be fat and round like the pics I see online. My other thought was a baby peppermint shrimp since that is the shrimp I had in that tank until recently and it was carrying eggs when I got it and I've heard they can carry sperm and fertilize for months after mating ... which would explain babies with only 1 shrimp. The only problem is that all of the pics I've found for peppermint shrimp larvae/babies seem to be huge heads and skinny bodies ... nothing like this one.

Can anyone offer any thoughts? Names? Pics?

For size, this is a medium food storage container on top of a dish towel. It is smaller that some of the amphipods (I think!)

 

Ok someone on another forum said it looks like Monocorophium insidiosum and after looking it up, I agree.

Is it safe to assume they are just another beneficial bug?

 

If it's mysid, SCORE! If it's mantis, SCORE! Your tank will eat some mysid. If it' mantis raise that sucker in your pod tank and sell him. Many reefers would LOVE to own a mantis for a species only nano.

 

I'm not sold on the mysid shrimp ... the body is pretty much the same width the whole way down and it's flat ... I've seen tiny shrimp in the big tank at night and they all look like regular shrimp, even teeny tiny ones ... this one looks flat and wide, like a mantis shrimp ... or this other pod that was suggested. I kind of don't think it's mantis either though ... and as far as tubes ... since removing my Skimmer and all from the sump (need new pump) the left side is empty and there seem to be tubes of some sort on the floor of that chamber. Not sure if it's critters or just detritus build up from the flow but it didn't seem to blow away when I threw a small circulation pump in there. Haven't investigated further. The problem is these things are just so dang tiny that I can't see detail as well as I'd like and I definitely can't photograph it. I wonder if I got out my macro lens on my DSLR if that would work!

 

As far as the mysid I believe I have running around in the tank ... they seem to be much like my cherry shrimp and the shrimplets look just like tiny adults ... they may not at all baby stages but I've seen some pretty tiny clearish shrimp running around the tank at night. Not as small as this thing though.

 

I had a mantis shrimp hitchhike in on some rock once a long time ago. He was tiny but literally would chase food when I feed the tank and steal food from other shrimp and tank mates. They are bold and very smart for a shrimp.

 

I have video but it won't upload. I'll have to mess with YouTube later because it hasn't been working for me lately. Those stills are from the video.