Side views of the supra-alveolar densities reveal some filamentous structures. A. Two views onto the plasma membrane (blue, top) and the IMC (yellow) from the same tomogram. The supra-alveolar densities are highlighted in red, and the red arrowheads indicate potential filaments. Note that most filaments are in parallel to the direction of the electron beam (black arrow). B. A volume rendered visualization of a side view onto the IMC. Red arrowheads point to the filament-like densities. The horizontal direction of the electron beam is indicated with a black arrow below panels B-D. C. A 10 nm thick section of a tomogram from a different sporozoite viewed from the side onto the IMC. Red arrowheads point to the filament-like densities. Scale bar: 100 nm (for B-E). D. Volume rendered representations of the density between the IMC and the plasma membrane for the tomogram from figure 2B with three different levels of threshold applied for visualization of the particular voxels (left panel - highest, right panel - lowest). Red arrowheads in the middle panel indicate filamentous structures. The direction of the electron beam is indicated with the black arrow below the panel.