Stomach or Heart? - Shrimp

I filmed this transparent Cuapetes sp. shrimp and noticed that behind it's eyes was a dark sort of kidney-shaped organ that was pumping up and down. Having had a look at some crustacean anatomy books I'm not sure if this is it's heart or it's stomach.

[vimeohd]37919149[/vimeohd]

Any help appreciated

Kaj

I would venture a guess and say stomach. Trying to shrimp-eye the video by keeping one eye on the front end, and the other eye on the organ in question- you can kindof see the feeding linked to the movement (dont try this at home, you eyes might stay like that forever! ).

Thats damn neat though! Thanks!