Bothnian Bay Bothnian Sea Baltic Proper Arkona Basin Kattegat (A) 2.2 2.4 2.8 2.9 3.1 4.7 5.2 5.4 5.6 5.8 6.1 6.6 6.8 7 7.2 7.2 7.3 8 9.7 19.8 24.2 0.3 0.6 1.2 3 (%)
OTU_144 Bacillariophyta;Bacillariophyta_X;Polar−centric−Mediophyceae;
OTU_136 Bacillariophyta;Bacillariophyta_X;Polar−centric−Mediophyceae;Chaetoceros;
OTU_125 Bacillariophyta;Bacillariophyta_X;Polar−centric−Mediophyceae;Chaetoceros;Chaetoceros+muellerii_strain2;
OTU_94 Bacillariophyta;Bacillariophyta_X;Raphid−pennate;
Bothnian Bay Bothnian Sea Baltic Proper Arkona Basin Kattegat 2.2 2.4 2.8 2.9 3.1 4.7 5.2 5.4 5.6 5.8 6.1 6.6 6.8 7 7.2 7.2 7.3 8 9.7 19.8 24.2 (B) 0.3 0.6 1.2 3 10 20 (%) OTU_393 Dinophyceae;
OTU_112 Dinophyceae;Dinophyceae_X;Dinophyceae_XX;
OTU_67 Dinophyceae;Dinophyceae_X;Dinophyceae_XX;Alexandrium;
OTU_23 Dinophyceae;Dinophyceae_X;Dinophyceae_XX;Ceratium;Ceratium+sp.;
OTU_222 Dinophyceae;Dinophyceae_X;Dinophyceae_XX;Ceratium;Ceratium+tenue;
OTU_32 Dinophyceae;Dinophyceae_X;Dinophyceae_XX;Dinophyceae_XXX;
OTU_221 Dinophyceae;Dinophyceae_X;Dinophyceae_XX;Dinophyceae_XXX;Dinophyceae_XXX+sp._strain35;
OTU_95 Dinophyceae;Dinophyceae_X;Dinophyceae_XX;Dinophyceae_XXX;Dinophyceae_XXX+sp.;
OTU_168 Dinophyceae;Dinophyceae_X;Dinophyceae_XX;Dinophyceae_XXX;Dinophyceae_XXX+sp.;
OTU_118 Dinophyceae;Dinophyceae_X;Dinophyceae_XX;Heterocapsa;Heterocapsa+nei/rotundata_strain1;
OTU_107 Dinophyceae;Dinophysiales;Dinophysaceae_Oxyphysaceae;
OTU_25 Dinophyceae;Suessiales;Suessiales_X;
OTU_31 Dinophyceae;Suessiales;Suessiales_X;
OTU_41 Dinophyceae;Suessiales;Suessiales_X;
OTU_1339 Dinophyceae;Suessiales;Suessiales_X;
OTU_1568 Dinophyceae;Suessiales;Suessiales_X;
OTU_1788 Dinophyceae;Suessiales;Suessiales_X;
Bothnian Bay Bothnian Sea Baltic Proper Arkona Basin Kattegat (C) 2.2 2.4 2.8 2.9 3.1 4.7 5.2 5.4 5.6 5.8 6.1 6.6 6.8 7 7.2 7.2 7.3 8 9.7 19.8 24.2 0.3 0.6 1.2 3 10 (%) OTU_9 Trebouxiophyceae;
OTU_833 Trebouxiophyceae;
OTU_1606 Trebouxiophyceae;
OTU_193 Trebouxiophyceae;Chlorellales;Chlorellales_X;
OTU_182 Trebouxiophyceae;Chlorellales;Chlorellales_X;Chloroparva;Chloroparva+pannonica;
OTU_163 Trebouxiophyceae;Chlorellales;Chlorellales_X;Picochlorum;Picochlorum+sp.;
OTU_30 Trebouxiophyceae;Trebouxiophyceae_X;Trebouxiophyceae_XX;Choricystis;Choricystis+sp.;
(D) Bothnian Bay Bothnian Sea Baltic Proper Arkona Basin Kattegat 2.2 2.4 2.8 2.9 3.1 4.7 5.2 5.4 5.6 5.8 6.1 6.6 6.8 7 7.2 7.2 7.3 8 9.7 19.8 24.2 0.3 0.6 1.2 3 6 (%)
OTU_85 Cryptophyceae;Cryptophyceae_X;Basal_Cryptophyceae−1;Basal_Cryptophyceae−1_X;Basal_Cryptophyceae−1_X+sp.;
OTU_141 Cryptophyceae;Cryptophyceae_X;Basal_Cryptophyceae−1;Basal_Cryptophyceae−1_X;Basal_Cryptophyceae−1_X+sp.;
OTU_28 Cryptophyceae;Cryptophyceae_X;Cryptomonadales;
OTU_72 Cryptophyceae;Cryptophyceae_X;Cryptomonadales;
OTU_1312Cryptophyceae;Cryptophyceae_X;Cryptomonadales;
OTU_56 Cryptophyceae;Cryptophyceae_X;Cryptomonadales;Cryptomonadales_X;Cryptomonadales_X+sp.;
Bothnian Bay Bothnian Sea Baltic Proper Arkona Basin Kattegat 2.2 2.4 2.8 2.9 3.1 4.7 5.2 5.4 5.6 5.8 6.1 6.6 6.8 7 7.2 7.2 7.3 8 9.7 19.8 24.2 0.01 0.03 0.06 0.2 0.6 (%) (E)
OTU_1098 Mamiellaceae;Mamiella;Mamiella+gilva;
OTU_1013 Mamiellaceae;Mamiellaceae_X;Mamiellaceae_X+sp.;
OTU_605 Mamiellaceae;Mantoniella;Mantoniella+squamata;
OTU_137 Mamiellaceae;Micromonas;
OTU_340 Mamiellaceae;Micromonas;
OTU_412 Mamiellaceae;Micromonas;
OTU_932 Mamiellaceae;Micromonas;
OTU_526 Mamiellaceae;RCC391;
Bothnian Bay Bothnian Sea Baltic Proper Arkona Basin Kattegat 2.2 2.4 2.8 2.9 3.1 4.7 5.2 5.4 5.6 5.8 6.1 6.6 6.8 7 7.2 7.2 7.3 8 9.7 19.8 24.2 1 3 6 15 25 (%) (F) OTU_90 Litostomatea;Cyclotrichia; OTU_166 Litostomatea;Cyclotrichia; OTU_27 Litostomatea;Cyclotrichia;Cyclotrichia_X; OTU_49 Litostomatea;Cyclotrichia;Cyclotrichia_X; OTU_34 Litostomatea;Cyclotrichia;Cyclotrichia_X;Cyclotrichia_XX;Cyclotrichia_XX+sp._strain10; OTU_148 Litostomatea;Cyclotrichia;Cyclotrichia_X;Cyclotrichia_XX;Cyclotrichia_XX+sp._strain17; OTU_115 Litostomatea;Cyclotrichia;Cyclotrichia_X;Cyclotrichia_XX;Cyclotrichia_XX+sp.; OTU_86 Litostomatea;Cyclotrichia;Mesodiniidae; OTU_152 Oligohymenophorea;Scuticociliatia;Cinetochilidae; OTU_45 Oligohymenophorea;Sessilida;Vorticellidae; OTU_2 Oligohymenophorea;Sessilida;Vorticellidae;Vorticella; OTU_24 Phyllopharyngea;Suctoria;Acinetidae;Acineta; OTU_101 Phyllopharyngea;Suctoria;Tokophryidae; OTU_87 Prostomatea;Prostomatea_X;Placidae; OTU_42 Prostomatea;Prostomatea−1;Prostomatea−1_X;Prostomatea−1_XX; OTU_20 Spirotrichea;Choreotrichia;Metacylididae;Helicostomella;Helicostomella+subulata; OTU_15 Spirotrichea;Choreotrichia;Strobilidiidae_X;Strobilidiidae_X+sp.; OTU_48 Spirotrichea;Choreotrichia;Strobilidiidae; OTU_35 Spirotrichea;Choreotrichia;Strobilidiidae;Pelagostrobilidium; OTU_111 Spirotrichea;Choreotrichia;Strobilidiidae;Strobilidiidae_X; OTU_68 Spirotrichea;Choreotrichia;Strobilidiidae;Strobilidiidae_X;Strobilidiidae_X+sp.; OTU_60 Spirotrichea;Choreotrichia;Tintinnidae;Tintinnidae_X;Tintinnidae_X+sp.; OTU_135 Spirotrichea;Choreotrichia;Tintinnidiidae;Tintinnidium;Tintinnidium+mucicola; OTU_18 Spirotrichea;Euplotia;Euplotidae;Euplotes;Euplotes+sp.; OTU_104 Spirotrichea;Hypotrichia; OTU_43 Spirotrichea;Oligotrichia; OTU_74 Spirotrichea;Oligotrichia;Strombidiidae; OTU_82 Spirotrichea;Oligotrichia;Strombidiidae; OTU_14 Spirotrichea;Oligotrichia;Strombidiidae;Strombidiidae_X; OTU_38 Spirotrichea;Oligotrichia;Strombidiidae;Strombidiidae_X;Strombidiidae_X+sp._strain3; OTU_46 Spirotrichea;Oligotrichia;Strombidiidae;Strombidiidae_X;Strombidiidae_X+sp.; OTU_5 Spirotrichea;Oligotrichia;Strombidiidae;Strombidium;Strombidium+basimorphum; OTU_13 Spirotrichea;Oligotrichia;Strombidiidae;Strombidium;Strombidium+biarmatum; OTU_108 Spirotrichea;Oligotrichia;Strombidiidae;Strombidium;Strombidium+conicum;
Bothnian Bay Bothnian Sea Baltic Proper Arkona Basin Kattegat (G)
2.2 2.4 2.8 2.9 3.1 4.7 5.2 5.4 5.6 5.8 6.1 6.6 6.8 7 7.2 7.2 7.3 8 9.7 19.8 24.2 1 2 3 5 10 (%)
OTU_98 Filosa−Imbricatea;Filosa−Imbricatea_X;Novel−clade−2;
OTU_156 Filosa−Imbricatea;Filosa−Imbricatea_X;Novel−clade−2;Novel−clade−2_X;
OTU_106 Filosa−Imbricatea;Filosa−Imbricatea_X;Novel−clade−2;Novel−clade−2_X;Novel−clade−2_X+sp._strain10;
OTU_33 Filosa−Imbricatea;Filosa−Imbricatea_X;Novel−clade−2;Novel−clade−2_X;Novel−clade−2_X+sp._strain15;
OTU_16 Filosa−Thecofilosea;Cryomonadida;Cryomonadida_X;Cryomonadida_XX;
OTU_105 Filosa−Thecofilosea;Cryomonadida;Cryothecomonas−lineage;Cryothecomonas;Cryothecomonas+aestivalis;
OTU_129 Filosa−Thecofilosea;Cryomonadida;Cryothecomonas;
OTU_37 Filosa−Thecofilosea;Cryomonadida;Protaspa−lineage;Protaspa−lineage_X;
OTU_123 Filosa−Thecofilosea;Cryomonadida;Protaspa−lineage;Protaspa−lineage_X;
OTU_57 Filosa−Thecofilosea;Cryomonadida;Protaspa−lineage;Protaspa−lineage_X;Protaspa−lineage_X+sp._strain16;
OTU_114 Filosa−Thecofilosea;Ebriida;
OTU_55 Filosa−Thecofilosea;Ebriida;Botuliformidae;Protaspa−lineage_X;Protaspa−lineage_X+sp._strain39;
OTU_17 Filosa−Thecofilosea;Ebriida;Ebriidae;Ebria;Ebria+tripartita;
OTU_78 Filosa−Thecofilosea;Ebriida;TAGIRI1−lineage;TAGIRI1−lineage_X;
OTU_47 Filosa−Thecofilosea;Ebriida;TAGIRI1−lineage;TAGIRI1−lineage_X;TAGIRI1−lineage_X+sp.;
OTU_58 Filosa−Thecofilosea;Filosa−Thecofilosea_X;Mataza−lineage;
OTU_89 Filosa−Thecofilosea;Filosa−Thecofilosea_X;Mataza−lineage;
OTU_88 Filosa−Thecofilosea;Filosa−Thecofilosea_X;Mataza−lineage;Mataza−lineage_X;
OTU_731 Filosa−Thecofilosea;Filosa−Thecofilosea_X;Mataza−lineage;Mataza−lineage_X;
OTU_196 Novel−clade−10−12;Novel−clade−10;Novel−clade−10_X;Novel−clade−10_XX;Novel−clade−10_XX+sp.;
Bothnian Bay Bothnian Sea Baltic Proper Arkona Basin Kattegat (H) 2.2 2.4 2.8 2.9 3.1 4.7 5.2 5.4 5.6 5.8 6.1 6.6 6.8 7 7.2 7.2 7.3 8 9.7 19.8 24.2 0.2 0.5 1 2 3 (%) OTU_1931 MAST−1;MAST−1C; OTU_1254 MAST−1;MAST−1C;MAST−1C_X; OTU_51 MAST−1;MAST−1C;MAST−1C_X;MAST−1C_X+sp.; OTU_713 MAST−1;MAST−1C;MAST−1C_X;MAST−1C_X+sp.; OTU_1717 MAST−1;MAST−1C;MAST−1C_X;MAST−1C_X+sp.; OTU_730 MAST−12;MAST−12_X; OTU_690 MAST−12;MAST−12A; OTU_721 MAST−12;MAST−12A; OTU_1555 MAST−12;MAST−12A; OTU_756 MAST−12;MAST−12A;MAST−12A_X;MAST−12A_X+sp.; OTU_276 MAST−12;MAST−12C; OTU_471 MAST−12;MAST−12C; OTU_1293 MAST−12;MAST−12C; OTU_1346 MAST−2; OTU_99 MAST−2;MAST−2A;MAST−2A_X;MAST−2A_X+sp.; OTU_1631 MAST−2;MAST−2D;MAST−2D_X; OTU_50 MAST−2;MAST−2D;MAST−2D_X;MAST−2D_X+sp.; OTU_928 MAST−3;MAST−3A; OTU_580 MAST−3;MAST−3C;MAST−3C_X;MAST−3C_X+sp.; OTU_305 MAST−3;MAST−3E;MAST−3E_X;MAST−3E_X+sp.; OTU_800 MAST−3;MAST−3E;MAST−3E_X;MAST−3E_X+sp.; OTU_563 MAST−3;MAST−3F;MAST−3F_X;MAST−3F_X+sp.; OTU_337 MAST−3;MAST−3J; OTU_716 MAST−3;MAST−3J; OTU_803 MAST−3;MAST−3J;MAST−3J_X;MAST−3J_X+sp.; OTU_381 MAST−4;MAST−4D;MAST−4D_X;MAST−4D_X+sp.; OTU_145 MAST−6;MAST−6_X; OTU_245 MAST−6;MAST−6_X;MAST−6_XX; OTU_644 MAST−6;MAST−6_X;MAST−6_XX;MAST−6_XX+sp.; OTU_1466 MAST−8;MAST−8B;MAST−8B_X; Supplementary gure 5. Major OTUs in seven protist classes. (A) Bacillariophyta. (B) Dinophyceae. (C) Trebouxiophyceae. (D) Cryptophyceae. (E) Mamiellophyceae , (F) Ciliophora, (G) Cercozoa (H) MAST. -3 OTUs displaying > 10 mean abundance are shown in most cases, all OTUs are shown in (E) Mamiellophyceae and (H) MAST.