Achnanthes affinis Grunow, 1880 accepted as Achnanthidium affine (Grunow) Czarnecki, 1994 accepted as Achnanthes affinis var. affinis Grunow in Cleve & Grunow, 1880 (original description)
Achnanthes biasolettiana Grunow, 1880 accepted as Achnanthidium pyrenaicum (Hustedt) H.Kobayasi, 1997 accepted as Achnanthes pyrenaica var. pyrenaica Hustedt, 1939 (original description)
Achnanthes lanceolata (Brébisson ex Kützing) Grunow, 1880 accepted as Planothidium lanceolatum (Brébisson ex Kützing) Bukhtiyarova, 1999 (new combination reference)
Achnanthes minutissima var. cryptocephala Grunow, 1880 (original description)
Actinocyclus roperi (Brébisson) Grunow ex Van Heurck, 1881 accepted as Eupodiscus roperi Brébisson, 1870 (new combination reference)
Amphiprora hyalina Eulenstein ex Van Heurck, 1880 (original description)
Amphora decipiens Grunow in Van Heurck, 1883 (original description)
Amphora globulosa var. perpusilla Grunow, 1880 (original description)
Amphoropsis decipiens Grunow, 1881 (original description)
Anaulus mediterraneus var. intermedia Grunow in Van Heurck, 1882 (original description)
Asterionella formosa var. gracillima (Hanztsch) Grunow, 1881 accepted as Diatoma gracillimum Hantzsch in Rabenhorst, 1861 (new combination reference)
Asterionella notata Grunow ex Van Heurck, 1881 accepted as Asterionella bleakeleyi var. notata Grunow, 1867 (new combination reference)
Biddulphia rhombus var. trigona Cleve ex Van Heurck, 1882 (original description)
Biddulphia subaequa var. baltica Grunow in Van Heurck, 1882 (original description)
Chaetoceros anglicus Grunow in Van Heurck, 1882 (original description)
Chaetoceros distans var. subsecunda Grunow in Van Heurck, 1883 (original description)
Chaetoceros eibenii Grunow, 1882 (original description)
Cocconeis scutellum f. parva Grunow, 1880 (original description)
Cocconeis scutellum var. minutissima Grunow, 1880 (original description)
Cyclotella comta var. radiosa Grunow in Van Heurck, 1882 (original description)
Cyclotella striata var. baltica Grunow in Van Heurck, 1882 (original description)
Cyclotella striata var. subsalina (Grunow) Hustedt, 1928 accepted as Cyclotella subsalina Grunow, 1882 (original description)
Cyclotella subsalina Grunow, 1882 (original description)
Cymatopleura elliptica var. hibernica (W.Smith) Hustedt accepted as Cymatopleura hibernica W.Smith, 1851 accepted as Surirella hibernica (W.Smith) D.Kapustin & O.Kryvosheia in Kryosheia & Kapustin, 2019 (new combination reference)
Cymatosira belgica Grunow, 1881 (original description)
Cymbella cistula var. maculata (Kützing) Van Heurck, 1885 accepted as Frustulia maculata Kützing, 1833 (new combination reference)
Cymbella lanceolata (C.Agardh) C.Agardh, 1830 accepted as Frustulia lanceolata C.Agardh, 1827 (new combination reference)
Cymbella tumida (Brébisson) van Heurck, 1880 accepted as Cocconema tumidum f. tumidum Brébisson ex Kützing, 1849 (new combination reference)
Diatoma tenue var. hybrida Grunow in Van Heurck, 1881 (original description)
Diatoma vulgare var. constricta Grunow in Van Heurck, 1881 accepted as Diatoma vulgaris var. constricta Grunow, 1881 (original description)
Ditylum brightwellii (T.West) Grunow, 1885 (new combination reference)
Eucampia cornuta (Cleve) Grunow, 1883 accepted as Moelleria cornuta Cleve, 1873 accepted as Neomoelleria cornuta (Cleve) S.Blanco & C.E.Wetzel, 2016 (new combination reference)
Eunotia arcus var. bidens Grunow, 1881 (original description)
Eunotia arcus var. tenella Grunow, 1881 (original description)
Eunotia faba (Ehrenberg) Grunow, 1881 accepted as Himantidium faba Ehrenberg, 1854 (new combination reference)
Eunotia incisa W.Smith ex W.Gregory, 1854 (original description)
Eunotia lunaris (Ehrenberg) Grunow, 1882-1885 accepted as Synedra lunaris var. lunaris Ehrenberg, 1832 (original description)
Eunotia lunaris (Ehrenberg) Grunow, 1882-1885 accepted as Synedra lunaris var. lunaris Ehrenberg, 1832 (new combination reference)
Eunotia lunaris var. subarcuata (Nägeli) Grunow, 1881 accepted as Synedra subarcuata Naegeli ex Kützing, 1849 (new combination reference)
Eunotia minor (Kützing) Grunow, 1881 accepted as Himantidium minus Kützing, 1844 (new combination reference)
Eunotia praerupta f. inflata (Grunow) J.Frenguelli, 1924 (original description)
Fragilaria construens f. venter (Ehrenberg) Hustedt, 1957 accepted as Fragilaria venter var. venter Ehrenberg, 1854 (new combination reference)
Fragilaria lapponica f. lapponica Grunow in Van Heurck, 1881 (original description)
Fragilaria mutabilis var. intercedens Grunow, 1881 (original description)
Fragilaria parasitica var. subconstricta Grunow, 1881 (original description)
Fragilaria virescens f. subsalina Grunow in Van Heurck, 1881 (original description)
Gomphonema acuminatum var. brebissonii (Kützing) Grunow, 1880 accepted as Gomphonema brebissonii Kützing, 1849 (new combination reference)
Gomphonema parvulum (Kützing) Kützing, 1849 (new combination reference)
Grammatophora adriatica Grunow in Van Heurck, 1881 (original description)
Grammatophora marina var. adriatica Grunow, 1881 (original description)
Hemiaulus hauckii Grunow ex Van Heurck, 1882 (original description)
Mastogloia elliptica (C.Agardh) Cleve, 1893 (new combination reference)
Melosira crenulata var. ambigua Grunow, 1882 (original description)
Melosira crenulata var. valida Grunow, 1882 (original description)
Melosira hyperborea Grunow, 1882 (original description)
Navicula bulnheimii var. bulnheimii Grunow, 1880 (original description)
Navicula exilis Grunow, 1880 (original description)
Navicula falaisensis Grunow in Van Heurck, 1880 accepted as Encyonopsis falaisensis (Grunow) Krammer, 1997 (original description)
Navicula falaisensis f. falaisensis Grunow in Van Heurck, 1880 accepted as Encyonopsis falaisensis (Grunow) Krammer, 1997 (original description)
Navicula gottlandica Grunow, 1880 (original description)
Navicula legumen f. decrescens Grunow in Van Heurck, 1880 (original description)
Navicula liburnica Grunow, 1860 (original description)
Navicula minima f. minima Grunow in Van Heurck, 1880 (original description)
Navicula minuscula var. bahusiensis Grunow, 1880 (original description)
Navicula minuscula var. minuscula Grunow, 1880 (original description)
Navicula muralis f. muralis Grunow in Van Heurck, 1880 (original description)
Navicula peregrina var. meniscus (J.Schumann) Grunow, 1895 accepted as Navicula meniscus var. meniscus Schumann, 1867 (new combination reference)
Navicula perminuta Grunow, 1880 (original description)
Navicula subhamulata var. subhamulata Grunow in Van Heurck, 1880 (original description)
Navicula ventricosa var. truncatula Grunow, 1880 (original description)
Nitzschia elegantula Grunow, 1881 (original description)
Nitzschia frustulum var. perpusilla (Rabenhorst) Van Heurck, 1885 accepted as Nitzschia perpusilla f. perpusilla Rabenhorst, 1861 (new combination reference)
Nitzschia nana Grunow, 1881 (original description)
Nitzschia paleacea Grunow in Van Heurck, 1881 (original description)
Nitzschia tryblionella var. littoralis (Grunow) Grunow, 1881 accepted as Nitzschia littoralis var. littoralis Grunow in Cleve & Grunow, 1880 (new combination reference)
Plagiogramma vanheurckii Grunow, 1881 (original description)
Plagiotropis vanheurckii Grunow, 1883 (original description)
Rhizosolenia alata f. gracillima (Cleve) Gran, 1908 accepted as Rhizosolenia gracillima Cleve, 1881 (new combination reference)
Rhizosolenia alata var. gracillima (Cleve) Grunow ex Van Heurck, 1880 accepted as Rhizosolenia gracillima Cleve, 1881 (new combination reference)
Stephanodiscus astraea var. minutula (Kützing) Grunow, 1882 accepted as Cyclotella minutula Kützing, 1844 † (new combination reference)
Synedra acus var. angustissima (Grunow) van Heurck, 1885 accepted as Synedra delicatissima var. mesoleia Grunow in Van Heurck, 1881 (original description)
Synedra affinis f. obtusa Arnott ex Van Heurck, 1881 (original description)
Synedra delicatissima var. angustissima Grunow, 1881 (original description)
Synedra delicatissima var. mesoleia Grunow in Van Heurck, 1881 (original description)
Synedra rumpens var. scotica Grunow, 1881 (original description)
Tabellaria binalis (Ehrenberg) Grunow, 1881 accepted as Fragilaria binalis Ehrenberg, 1854 (new combination reference)
Tabellaria fenestrata var. asterionelloides Grunow, 1881 (original description)
Tabellaria fenestrata var. intermedia Grunow, 1881 (original description)