FIGURES 58–67. 58–61. Achnanthes apiculata comb. nov. 62–64 in Achnanthes citronella, A. trachyderma comb. nov. (Bacillariophyta) and allied taxa pertaining to the same morphological group

FIGURES 58–67. 58–61. Achnanthes apiculata comb. nov. 62–64. Achnanthes cf. mammalis. 65–67. Achnanthes obesa comb. nov. 58. Individual from BM 1753, note the SV oblong rectangular areolae (arrow) and the position of the underlying RV extended and narrow stauros (arrowheads). 59. Apical areolae (arrow). 60. Laciniate marginal striae around the stauros (arrows). 60, 61. RV strongly radiate striae (arrowheads). 62, 63. Individual from BM 2887 with biseriate SV striae (arrowheads). 62. Apices free of areolae. 64. RV striae strongly radiate, stauros extended and high, reaching half valve width. 65, 66. Individual from BM 2593. 67. Individual from BM 2736, note the lateral gibbosities. 65. SV rectangular areolae. 66. RV striae strongly bent on apices (arrowhead). 67. Butterfly RV stauros (arrowheads) and striae radiate and thin (arrow). Scale bars = 10 μm.