There are three mucosoflagellate parasites of the cat, Tetratrichomonasfelistomae, Pentatrichomonashominis, and Giardiafelis. Two of these parasites, T. felistomae and P. hominis are quite similar morphologically and live in the mouth and the cecum/colon, respectively. The other mucosoflagellate, G. felis is a parasite of the small intestine of the cat, and is quite different morphologically and behaviorally from the trichomonads in that it has two nuclei in the trophozoite stage and produces a resistant cyst stage. The trichomonads have only a single nucleus and no resistant stage as part of their biology..