1 Gomphonema sp. (6957, 6959) 2 Gomphonema olivaceoides (6958) 3 Gomphonema minusculum Krasske (6958) 4 Gomphonema lateripunctatum (6956) 5 Gomphonema pumilum? (6956) 6 Gomphonema bozenae (6957) 7 Gomphonema pseudobohemicum (6958) 8–12 Gomphonema caperatum (6958) 13 Pinnularia krammeri (6955) 14 Pinnularia sinistra (6956) 15 Pinnularia subanglica (6958) 16 Pinnularia sp. (6957) 17, 18 Pinnularia subcommutata (6957) 19 Pinnularia permicrostauron (6955) 20 Pinnularia viridis (6955). Scale bar: 10 µm.