Every accepted species in the genus is listed. A name links to its page when we hold at least three commercially licensed photographs of it. Where we do not, the row shows how many we actually found, which is usually none.
| Species | Authority | Usable photographs | Page |
|---|---|---|---|
| Hydrogonium croceum | (Brid.) Jan Kučera | 5 | documented |
| Hydrogonium amplexifolium | (Mitt.) P.C.Chen | 0 | below the evidence gate |
| Hydrogonium angustifolium | (Hook. & Grev.) Jan Kučera | 0 | below the evidence gate |
| Hydrogonium arcuatum | (Griff.) Wijk & Margad. | 0 | below the evidence gate |
| Hydrogonium bolleanum | (Müll.Hal.) A.Jaeger | 0 | below the evidence gate |
| Hydrogonium consanguineum | (Thwaites & Mitt.) Hilp. | 0 | below the evidence gate |
| Hydrogonium crozalsii | (H.Philib.) Podp. | 0 | below the evidence gate |
| Hydrogonium cruegeri | (Sond. ex Müll.Hal.) Jan Kučera | 0 | below the evidence gate |
| Hydrogonium dorrii | (Renauld & Cardot) Hilp. | 0 | below the evidence gate |
| Hydrogonium fontanum | (Müll.Hal.) A.Jaeger | 0 | below the evidence gate |
| Hydrogonium gregarium | (Mitt.) Jan Kučera | 0 | below the evidence gate |
| Hydrogonium hiroshii | (K.Saito) Jan Kučera | 0 | below the evidence gate |
| Hydrogonium inflexum | (Duby) P.C.Chen | 0 | below the evidence gate |
| Hydrogonium javanicum | (Dozy & Molk.) Hilp. | 0 | below the evidence gate |
| Hydrogonium leucobasis | (Dixon) W.Schultze-Motel | 0 | below the evidence gate |
| Hydrogonium leucodontoides | Gangulee | 0 | below the evidence gate |
| Hydrogonium majusculum | (Müll.Hal.) P.C.Chen | 0 | below the evidence gate |
| Hydrogonium mamatkulovii | Laz. | 0 | below the evidence gate |
| Hydrogonium novoguinense | (Broth.) P.C.Chen | 0 | below the evidence gate |
| Hydrogonium orientale | (F.Weber) Jan Kučera | 0 | below the evidence gate |
| Hydrogonium patulifolium | J.Froehl. | 0 | below the evidence gate |
| Hydrogonium pseudoehrenbergii | (M.Fleisch.) P.C.Chen | 0 | below the evidence gate |
| Hydrogonium rechingeri | (Broth.) W.Schultze-Motel | 0 | below the evidence gate |
| Hydrogonium subcomosum | (Broth.) P.C.Chen | 0 | below the evidence gate |
| Hydrogonium subpellucidum | (Mitt.) Hilp. | 0 | below the evidence gate |
| Hydrogonium williamsii | P.C.Chen | 0 | below the evidence gate |
This site is commercial, so it can only publish photographs licensed for commercial use. Roughly three quarters of the photographs on iNaturalist are CC BY-NC, which excludes them. A species needs at least three usable photographs before we will build it a page, because a page with one picture and no traits tells you nothing you could not get from a search result, and generating hundreds of thousands of those is precisely the practice that got the previous version of this site deleted.
So the species above without a link are not errors and they are not omissions. They are real, accepted plants that we cannot yet document to the standard we hold ourselves to, and the count in the photographs column is exactly how far short we fall.