Table 1
Sampling sites with the habitats (EPL: Epilithic, EPP: Epipelic, EPF: Epiphytic)
| Site | River Basin | Abbreviation | Water body name – Substrate | Province |
|---|---|---|---|---|
| T1 | 1_Meriç-Ergene | MrEr | Süloğlu Reservoir – EPP | Edirne |
| T2 | Meriç River – Edirne Centrum – EPL | |||
| T3 | Meriç River – Küplü Köyü District – EPL | |||
| T4 | Kuleli Stream – EPL | |||
| T5 | Ergene River – Çiftlikköy District – EPL | |||
| T6 | Keşiflik Stream – EPL | Kırklareli | ||
| T7 | Kaynarlı Stream – EPL | |||
| T8 | Ergene River – EPL | Tekirdağ | ||
| T9 | Bent Stream – EPL | |||
| T10 | Ergene River – Uzunköprü District – EPL | |||
| T11 | 2_Marmara | MR | Ömerli Reservoir – EPP | İstanbul |
| T12 | Ilıca District – EPL | Yalova | ||
| T13 | Gökçedere – EPL | |||
| T14 | 3_Susurluk | SSR | Ulubat Lake – EPP | Bursa |
| T15 | Demirtaş Reservoir – EPP | |||
| T16 | Nilüfer Reservoir – EPL | |||
| T17 | Susurluk River – Karacabey District – EPL | |||
| T18 | Gölayağı Stream – EPL | |||
| T19 | Gölbaşı Reservoir – EPL | |||
| T20 | Deliçay – Kestel District – EPL | |||
| T21 | Kapıkaya Stream – EPL | |||
| T22 | Nilüfer Stream – Osmangazi District – EPL | |||
| T23 | Orhaneli Stream – Akçabük District – EPL | |||
| T24 | İkizcetepeler Reservoir – EPL | Balıkesir | ||
| T25 | Manyas Reservoir – EPP | |||
| T26 | Manyas Reservoir – EPL | |||
| T27 | Susurluk River – Bademli District – EPL | |||
| T28 | Susurluk River – Yeniköy District – EPL | |||
| T29 | Mürüvetler Stream – EPL | |||
| T30 | Simav Stream – Balıklı District – EPL | |||
| T31 | Ovaköy District – EPL | |||
| T32 | Simav Stream – Susurluk District – EPL | |||
| T33 | Kocaçay – Kızılköy District – EPL | |||
| T34 | Değirmendere Stream – EPL | |||
| T35 | Dursunbey Stream – EPL | |||
| T36 | Susurluk River – Sındırgı District – EPL | |||
| T37 | Kayaboğazı Reservoir – EPL | Kütahya | ||
| T38 | Simav River – Demirci Köyü District – EPL | |||
| T39 | Orhaneli Stream – Esatlar Köyü District – EPL | |||
| T40 | Orhaneli Stream – Hamitabat Köyü District – EPL | |||
| T41 | Aygırlar Stream – Domaniç District – EPL | |||
| T42 | Orhaneli Stream – Domaniç District – EPL | |||
| T43 | Topuk Stream – Domaniç District – EPL | |||
| T44 | Safa Stream – Domaniç District – EPL | |||
| T45 | Topuk/Safa junction – Domaniç District – EPL | |||
| T46 | Kocasu Str., before Kayaboğazı Reservoir – EPL | |||
| T47 | Kocasu Str., after Kayaboğazı Reservoir – EPL | |||
| T48 | Ilıcaksu Deresi – Spring – EPL | |||
| T49 | Karamanca District – EPL | |||
| T50 | Simav River – Spring – EPL | |||
| T51 | Mountainous stream – Egir District – EPL | |||
| T52 | Mountainous stream – Yavru District – EPL | |||
| T53 | Naşa District – EPL | |||
| T54 | Güneyköy District – EPL | |||
| T55 | Domaniç District – EPL | |||
| T56 | Domaniç entrance – EPL | |||
| T57 | Ilıcaksu-branch – EPL | |||
| T58 | 4_Kuzey Ege | KE | Şahindere – EPL | Balıkesir |
| T59 | Azap Lake – EPF | Aydın | ||
| T60 | 5_Gediz | GDZ | Gediz River – Naşa District – EPL | Kütahya |
| T61 | Gördes Reservoir – EPL | Manisa | ||
| T62 | 5_Gediz | GDZ | Marmara Lake – EPF | Manisa |
| T63 | Demirci Stream – EPL | |||
| T64 | Gediz River – EPL | |||
| T65 | Derbent Stream – EPL | |||
| T66 | Alaşehir Stream – EPL | |||
| T67 | Afşar 2 Reservoir – EPL | |||
| T68 | Murat Stream – EPL | |||
| T69 | Ağıl Stream – EPL | |||
| T70 | 6-Antalya | ANT | Aksu Stream – EPL | Antalya |
| T71 | Alara Stream – EPL | |||
| T72 | Eğirdir Lake – EPF | |||
| T73 | Kovada Lake – EPL | |||
| T74 | 7_Akarçay | AKR | Milyas Stream – EPL | Afyon |
| T75 | Kayalı Stream – EPL | |||
| T76 | 8_Sakarya | SKR | Ilıca Stream – EPL | Kütahya |
| T77 | Porsuk River – before Kütahya – EPL | |||
| T78 | Porsuk River – Gelinkaya District – EPL | |||
| T79 | Felent Stream – Spring – EPL | |||
| T80 | Felent Stream – Köprüören District – EPL | |||
| T81 | Kokar Stream – EPL | |||
| T82 | Altıntaş District – EPL | |||
| T83 | Büyük Akgöl Lake – EPF | Sakarya | ||
| T84 | 9_Konya | KNY | Mamasın Reservoir – EPL | Aksaray |
| T85 | İbrala Reservoir – EPL | Karaman | ||
| T86 | Meram District – EPL | Konya | ||
| T87 | Beyşehir Lake – Chara sample – EPF | |||
| T88 | Seydişehir District – EPL | |||
| T89 | Kocacay Stream – Spring – EPL | |||
| T90 | Derebucak Reservoir – EPP | |||
| T91 | Büyükköprü Stream – EPL | |||
| T92 | Susuz District – EPL | |||
| T93 | Beysehir Lake – EPL | |||
| T94 | İvriz Reservoir – EPP | |||
| T95 | Dipsiz Lake – EPP | |||
| T96 | 10_Kızılırmak | KZL | Kızılırmak River – Şarkışla District – EPL | Sivas |
| T97 | Fadlım River – EPL | |||
| T98 | Kızılırmak River – after Sivas – EPL | |||
| T99 | Kesikköprü Reservoir – EPL | Ankara | ||
| T100 | Uyuz Lake – EPF | |||
| T101 | Kızılırmak River – Bafra District – EPL | Samsun | ||
| T102 | Yay Lake – EPF | Kayseri | ||
| T103 | 11_Yeşilırmak | YŞL | Çakmak Reservoir – EPL | Samsun |
| T104 | Derinöz Reservoir – EPL | |||
| T105 | Mert River – EPL | |||
| T106 | Yeşilırmak River-1 – EPL | |||
| T107 | Kelkit River – EPL | |||
| T108 | Kurtun River – EPL | |||
| T109 | Elgazi Stream – EPL | |||
| T110 | Karakuş Stream – EPL | |||
| T111 | Terme Stream – EPL | |||
| T112 | Yeşilırmak River-2 – EPL | Sivas | ||
| T113 | Yeşilırmak River-3 – EPL | |||
| T114 | Çekerek River – EPL | |||
| T115 | Çakraz Stream – EPL | |||
| T116 | Gölbel Lake – EPP | Çorum | ||
| T117 | 12_Eastern Black Sea | EBL | Moçar Stream – EPL | Artvin |
| T118 | Tatos Lake – EPL | |||
| T119 | Uzungöl Lake – EPL | Trabzon | ||
| T120 | 13_Euphrates–Tigris | ET | Gördelli Stream – EPL | Erzurum |
| T121 | Tuzla Stream – EPL | Erzincan | ||
| T122 | Karasu Stream – EPL | Gaziantep | ||
| T123 | Altınsu Stream – EPL | Mardin | ||
| T124 | Murat River – EPL | Ağrı | ||
| T125 | İnekli Lake – EPL | Adıyaman |

Figure 1
Map of the study area. Sites codes (T1–T125) for each river basin are listed in Table 1.
Table 2
Distribution of the species in Turkey according to Maraşlıoğlu & Gönülol (2019) and the current study.
| Species | Turkey (Maraşlıoğlu & Gönülol 2019) | Our results | River basin |
|---|---|---|---|
| Didymosphenia geminata | C | R | EBL (T117, T118) |
| Gomphonema acuminatum | C | R | KNY (T86); YŞL (T116) |
| G. cf. aequale | R | KNY (T86); ET (T120) | |
| G. affine | C | R | MrEr (T3, T4); KZL (T101) |
| G. affine var. rhombicum* | R | SSR (T17) | |
| G. angustatum | C | R | KNY (T86, T87) |
| G. angusticephalum* | R | SSR (T14); KZL (T99) | |
| G. angustius | R | R | SSR (T50, T56, T60) |
| G. augur | C | R | MeEr (T7); SSR (T43); SKR (T77); YŞL (T107) |
| G. brebissonii | R | R | KNY (T86) |
| G. calcifugum* | C | SSR (T34, T41, T44, T45, T49, T54) | |
| G. capitatum | R | R | KNY (T91) |
| G. cf. clavatulum | R | KZL (T99) | |
| G. elegantissimum* | R | AKR (T73); KNY (T86) | |
| G. exilissimum* | C | MrEr (T6); SSR (T37, T47, T57); SKR (T82); KNY (T94); YŞL (T115); ET (T123) | |
| G. cf. gracile | R | KZL (T99); ET (T118) | |
| G. graciledictum* | R | SSR (T17); GDZ (T62) | |
| G. insignaffine | R | R | GDZ (T60) |
| G. insigne | F | R | SSR (T53); SKR (T81) |
| G. italicum | R | C | SSR (T14, T24, T30, T40, T38); GDZ (T62, T65); SKR (T77, T80); KNY (T87); KZL (T99); YŞL (T108; T110) |
| G. italicum var. densistriatum* | R | ET (T125) | |
| G. cf. latelanceolatum | R | MeEr (T8); KE (T59) | |
| G. lateripunctatum | R | R | GDZ (T68); KNY (T85, T93); KZL (T112) |
| G. laticollum | R | R | GDZ (T61); AKR (T74); SKR (T77) |
| G. linearoides* | R | YŞL (T106) | |
| G. megalobrebissonii* | R | KNY (T95) | |
| G. micropus | F | C | MrEr (T7); SSR (T34); GDZ (T66); KNY (T92); YŞL (T115) |
| G. minusculum* | R | SSR (T37, T53); SKR (T79, T80) | |
| G. minutum | F | C | MrEr (T4); SSR (T18, T25, T26, T29, T30, T31, T33, T36, T38, T39, T40); YŞL (T103, T105) |
| G. minutum f. syriacum* | R | SSR (T19, T22, T23, T42) | |
| G. olivaceoides | F | R | SSR (T21) |
| G. olivaceum | C | R | MrEr (T9); SSR (T15); GDZ (T69); KNY (T87); ET (T121) |
| G. parvulum | C | C | MrEr (T6); SKR (T82); KNY (T84); YŞL (T103, T111); ET (124) |
| G. productum | F | R | SSR (T51) |
| G. cf. pseudaffine | R | KNY (T87); EBL (T118) | |
| G. pseudoaugur | R | R | SSR (T14) |
| G. pumilum | F | C | MrEr (T10); MR (T12, T13); SSR (T19, T21, T23, T27, T28, T29, T32, T34, T35, T41, T42, T46, T54, T55, T56); ANT (T70); SKR (T76, T77, T78, T81); KNY (T86, T87, T90); KZL (T99, T101); YŞL (T103, T107); ET (T122, T124) |
| G. pumilum var. rigidum | R | R | SSR (T54) |
| G. reediae* | R | GDZ (T61); KNY (T93) | |
| G. sarcophagus* | R | MR (T11); KNY (T86, T91) | |
| G. stonei | R | R | SSR (T48) |
| G. cf. subangustatum | R | KNY (T86) | |
| G. subcapitatum* | R | SKR (T83); EBL (T117) | |
| G. subclavatum | F | R | EBL (T118, T119) |
| G. supertergestinum | R | R | MeEr (T6); SSR (T28, T46, T54); SKR (T77); YŞL (T114) |
| G. tergestinum | F | C | SSR (T52); KZL (T96, T97, T98); YŞL (T103, T108, T114, T115); ET (T121) |
| G. vibrio | F | R | SSR (T51) |
| Gomphonema sp. 1 | R | KZL (T99) | |
| Gomphonema sp. 2 | R | KZL (101) | |
| Gomphonema sp. 3 | R | YŞL (T113) | |
| Gomphonema sp. 4 | R | SSR (T17, T33, T54); SKR (T77) | |
| Gomphosphenia holmquistii* | R | SSR (T54); KZL (T102) |
[i] Abbreviations: AKR – Akarçay, ANT – Antalya, EBL – Eastern Black Sea, ET – Euphrates–Tigris, GDZ – Gediz, KE – Kuzey Ege, KNY – Konya, KZL – Kızılırmak, MR – Marmara, MrEr – Meriç–Ergene, SKR – Sakarya, SSR – Susurluk, and YŞL – Yeşilırmak river catchments; * – new record for Turkey, C – common (reported in more than 10% of the literature), F – frequent (between 10% and 2% of the literature), R – rare (less than 2% of the literature)

Plate 1
2, 3 – Didymosphenia geminata (Lyngbye) M.Schmidt. Scale bar: 10 µm

Plate 2
4 – Gomphonema acuminatum Ehrenberg; 5, 6 – G. cf. aequale W. Gregory; 7 – G. affine Kützing; 8, 9 – G. affine var. rhombicum E. Reichardt; 10, 11 – G. angustatum (Kützing) Rabenhorst; 12, 13 – G. angusticephalum E. Reichardt & Lange-Bertalot; 14, 15 – G. angustius E. Reichardt; 16, 17 – G. augur Ehrenberg; 18 – G. brebissonii Kützing; 19, 20 – G. calcifugum Lange-Bertalot & E. Reichardt; 21 – G. capitatum Ehrenberg; 22 – Gomphonema cf. clavatulum E. Reichardt; 23, 24 – G. elegantissimum E. Reichardt & Lange-Bertalot. Scale bar: 10 µm

Plate 3
25, 26 – Gomphonema exilissimum (Grunow) Lange-Bertalot & E.Reichardt; 27–29 – Gomphonema cf. gracile Ehrenberg; 30 – G. graciledictum E.Reichardt; 31 – G. italicum var. densistriatum Levkov, Mitic-Kopanja & E. Reichardt; 32, 33 – G. cf. latelanceolatum Levkov, Mitic-Kopanja & E. Reichardt; 34–36 – G. lateripunctatum E. Reichardt & Lange-Bertalot; 37, 38 – G. linearoides Levkov; 39 – G. megalobrebissonii D.A.Chudaev, Kociolek & M.A.Golobova; 40, 41 – G. micropus Kützing; 42, 43 – G. minusculum Cleve-Euler; 44, 45 – G. minutum (C.Agardh) C.Agardh; 46, 47 – G. minutum f. syriacum Lange-Bertalot & E. Reichardt; 48 – G. olivaceoides Hustedt; 49 – G. olivaceum (Hornemann) Brébisson; 50, 51 – G. parvulum (Kützing) Kützing; 52, 53 – G. productum (Grunow) Lange-Bertalot & E. Reichardt; 54 – G. cf. pseudaffine Levkov, Mitic-Kopanja & E. Reichardt; 55 – G. pseudoaugur Lange-Bertalot; 56 – G. reediae Levkov, Mitic-Kopanja & E. Reichardt; 57, 58 – G. sarcophagus W. Gregory. Scale bar: 10 µm

Plate 4
59, 60 – G. cf subangustatum Lange-Bertalot, Cavacini, Tagliaventi & Alfinito; 61 – G. subcapitatum (Grunow) E. Reichardt & Levkov; 62, 63 – G. subclavatum (Grunow) Grunow; 64, 65 – G. vibrio Ehrenberg; 66 – Gomphonema sp. 1; 67 – Gomphonema sp. 2; 68, 69 – Gomphonema sp. 3; 70, 71 – Gomphonema sp. 4; 72 – Gomphosphenia holmquistii (Foged) Lange-Bertalot. Scale bar: 10 µm