monocystic

from The Collaborative International Dictionary of English v.0.48

monocystic \mon`o*cys"tic\, a. [See {Mono-}, and {Cyst}.]
   (Zool.)
   Of or pertaining to a division ({Monocystidea}) of the
   protozoan order {Gregarinida}, in which the body consists of
   one sac.
   [1913 Webster]