trophozoites of Gregarina cuneata from the mealworm, Tenebrio molitor, engaged in syzygy or sexual reproduction.  This photo was taken from a plastic-embedded specimen prepared from transmission electron microscopy.  The sections were one micrometer thick and stained with toluidine blue (black and white film).  The primite is the uppermost of the two trophozoites and the lower one is the satellite.  The upper portion of each cell is the protomerite and the lower, the deutomerite.  The epimerite remains attached to the host.  The detached protomerite/deutomerites engage each other in the host's lumen in this act called syzygy.  430x.