The Ultrastructure of Lankesterella hylae

SYNOPSIS. The ultrastructure of Lankesterella hylae was studied and numerous points of similarity to Plasmodium, Toxoplasma, Sarcocystis and Lankesterella garnhami were found. The protozoa were intracellular and lay within vacuoles containing vesicles, unusual membrane formations and dense granular material. The parasite was invested by a double membrane and had a micropyle, as well as membranous processes extending from the surface. At the anterior end were conoid and apical rings. The cell contained a nucleus, nucleolus, bipolar paranuclear vacuoles or bodies, a series of microtubules beneath the pellicle, endoplasmic reticulum, mitochondria, toxonemes and a variety of vacuoles. In addition, dense particles, similar to those related to the endoplasmic reticulum, were scattered throughout the cytoplasm.
The unusual membrane formations and vesicles in the periparasitic vacuoles were striking observations possibly related to the nutrition of the parasite.