Hannaea inaequidentata, apex details of pre-normal cells, external view, SEM 119 apex detail of Fig. 107 showing deflexed sternum (arrow) 120 apex detail of Fig. 108 showing irregular striae and small ocellulimbus (arrow) 121 Apex detail of Fig. 109 showing twisted valve 122 apex detail of Fig. 110 showing almost normal sternum and striae (two arrows) 123 apex detail of Fig. 111 showing twisted valve and not well-developed spines 124 apex detail of Fig. 112 showing well-developed spines and almost normal ocellulimbus. Scale bars: 2 μm (119–124).