Fig. 2 in Morphological and molecular phylogenetic characterization of Sarcocystis kani sp. nov. and other novel, closely related Sarcocystis spp. infecting small mammals and colubrid snakes in Asia

Fig. 2. Ultrastructure of Sarcocystis sp.1 from the mangrove snake in abdominal musculature of a Sprague-Dawley rat; a) One μm-thin section through a resin-embedded, toluidine-stained sarcocyst showing densely-packed cystozoites (CZ) that were contained in septate compartments; the arrow indicates the cyst wall with small protrusions, which are clearly visible because host cell (HC) tissue is removed at this position; b) gross view of the cyst wall and cystozoites in a longitudinal section; the black arrow indicates a thin septum that separated the compartments filled with cystozoites; protrusions (PT) were broad, short, and irregularshaped, often with a reticulate base that rested on a thin layer of ground substance (GS); c) cross-section of sarcocyst, showing the primary cyst wall at higher magnification to consist of electron-dense, knob-like structures with intermittent invaginations; it appeared as if the primary wall was fenestrated (asterisk) allowing exchange of fine granular material (arrowheads) between the interior and exterior of the cyst; the exterior space between the protrusions was entirely filled with granular substance. d) metrocytes exclusively divided by endodyogeny as only cells with two developing zoites (asterisks) were observed; the white arrow points at deposits of highly electron-dense matter that could form larger clusters in the GS of the septae.