Figure 1.  Synchytrium permicus sp. nov., silicified endoparasitic chytridiomycete from Skaar Ridge, Central Transantarctic Mountains, Antarctica. 1. Cross section of a root of an unidentified plant infected with sporangia and zoospores and zoospore-like bodies (larger zoospores). Note ruptured thin-walled sporangium (upper right arrow), and large zoospores (some possibly represent zygotes) (left and lower right horizontal arrows) externally located relative to the thick-walled sporangia (oblique arrows). Slide #21643, 11665 C-top, peel #1. Scale bar= 200 µm. 2. Thin-walled sporangium within hypertrophied host cell and sporangium lying free in the matrix. Arrow points to a group of zoospores located in a thin-walled sporangium (holotype of Synchytrium permicus). Slide #21644, 11653 C-top, peel #1. Scale bar= 50 µm. 3. Spherical to slightly elongated zoospores within host cells. Arrow indicates empty zoospores encysted on host surface. Slide #21643, 11665 C-top, peel #1. Scale bar= 10 µm. 4. Zoospores. Arrow shows an opaque thick short knob protruding from the body of a zoospore. Note centrally located opaque body. Slide #21644, 11653 C-top, peel #1. Scale bar= 10 µm. 5. Zoospores. Arrows indicate opaque threads originating from the central opaque body. Slide #21644, 11653 C-top, peel #1. Scale bar 10= µm. 6. Hemispherical zoospores encysted on host tissue. Slide #21643, 11665 C-top, peel #1.  Scale bar= 5 µm. 7. Elongate zoospore inside a host cell. Slide #21645, 11654 G-bot, peel #1.  Scale bar= 15 µm. 8. Large zoospores inside host tissue. Upper arrow shows a circular to irregular scar-like aperture on the surface of a zoospore with zoospore lumen partially empty of opaque contents. Left arrow indicates a narrow wall projection on the surface of a zoospore with zoospore lumen empty of opaque contents. Slide #21643, 11665 C-top, peel #1. Scale bar= 15 µm. 9. Large zoospore with extended margin (left arrow) and disaggregated opaque central body (right arrow). Slide #21646, 11654 F-top, peel #1α. Scale bar= 15 µm. 10. Infected host cell with two (right arrows) elongated and similarly sized bodies. White arrow indicates opaque inclusions. Lower left arrow shows distinct margin in upper body. Slide #21643, 11665 C-top, peel #1.  Scale bar= 20 µm.