Fig. 4
From: Parasites, pathogens and commensals in the “low-impact” non-native amphipod host Gammarus roeselii
Transmission electron micrograph of early spore development for Cucumispora roeselii n. sp. a Diplokaryotic meront displaying attached nuclei (N; white arrow). Note the thin cell membrane (black arrow). b Tetranucleate cell displaying four attached nuclei (N; white arrows) with a thickening cell wall (black arrow). c After division, two early diplokaryotic (N; white arrow) sporoblasts are produced with further cell membrane thickening (black arrow). d Early diplokaryotic (N; white arrow) sporoblast displaying further thickening of the cell membrane (black arrow). e The early sporoblast begins to become electron dense and condense with some early development of spore organelles such as the polar filament (black arrow). f Fully condensed sporoblast development stage present with electron dense cytoplasm and coiled polar filament (PF) and anchoring disk (AD). At this stage the formation of the early endospore is visible (white arrow). Scale-bars: 500 nm