Icthyophthirius multifiliis from a swordtail tropical fish.  This specimen was alive at the time of the photo and stained with methylene blue.  The cytostome opens to the top.  The cilia are apparent.  100x

Ichthyophthirius multifiliis trophozoite attached to a ctenoid fish scale of a swordtail. In vivo, unstained. 100x


Ichthyophthirius multifiliis trophozoite from a swordtail.  In vivo, unstained.  This frame reveals the opening to the cytostome to the far right.  The faint bands appearing obliquely are ciliary waves in the metachronal stroke.  400x