Piscciss Volann Prisoner

The Piscciss Volann Prisoners were some of the alien prisoners on Incarcecon in Ben 10: Secret of the Omnitrix.

History
Two were seen when Tetrax was explaining there are no rules on Incarcecon. One was seen when Gwen was exposed to everyone when Ben turned into Upchuck. Another was seen in the crowd surrounding Ben and Gwen. Both wore black collars with clear portions around their gills (presumabley a form of breathing apparatus).