. _:b75730178 "8403637" . . . _:b75403808 "AlgaeBase id" . _:b75403808 . _:b75403808 . "Nitzschia sigma var. rigida" . . "Nitzschia sigma var. rigida" . "Nitzschia sigma var. rigida Grunow ex Van Heurck, 1880" . _:b75730178 "GBIF id" . "76395" . . _:b75730178 . _:b76636943 "671471" . "671471" . _:b75730178 . "8403637" . . "e86a3f453092b1b60" . "Grunow ex Van Heurck, 1880" . . _:b76636943 . _:b76636943 . _:b75403808 "e86a3f453092b1b60" . _:b75403808 . _:b76636943 "WoRMS id" . . . . _:b76636943 . "Nitzschia sigma var. rigida" . . . _:b75730178 .