FIGURES 48–56 in Observations on a fragilarioid diatom found in inter-dune lakes of the Badain Jaran Desert (Inner Mongolia, China), with a discussion on the newly erected genus Williamsella Graeff, Kociolek & Rushforth

FIGURES 48–56. Scanning electron micrographs of whole valves of Fragilaria asiatica Hustedt from type material AS1395, Tibet. Figs 48, 49, 51,52. External views. Figs 50, 53–56. Internal views. Rimoportulae (arrows) can be present on each apex (Figs 49, 53, 56), or only present on one apex (Figs 48, 50–52, 54,55). Scale bars = 10 μm (Figs 48–51); = 20 μm (Figs 52–56).