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 |
|---|---|---|---|
| Houstonia caerulea | L. | 2,502 | documented |
| Houstonia pusilla | Schoepf | 1,053 | documented |
| Houstonia purpurea | L. | 713 | documented |
| Houstonia longifolia | Gaertn. | 435 | documented |
| Houstonia procumbens | (Walter ex J.F.Gmel.) Standl. | 397 | documented |
| Houstonia serpyllifolia | Michx. | 135 | documented |
| Houstonia acerosa | (A.Gray) Benth. & Hook.f. | 105 | documented |
| Houstonia micrantha | (Shinners) Terrell | 105 | documented |
| Houstonia wrightii | A.Gray | 69 | documented |
| Houstonia rubra | Cav. | 37 | documented |
| Houstonia humifusa | (Engelm. ex A.Gray) A.Gray | 22 | documented |
| Houstonia rosea | (Raf.) Terrell | 22 | documented |
| Houstonia canadensis | Willd. | 9 | documented |
| Houstonia subviscosa | (C.Wright ex A.Gray) A.Gray | 6 | documented |
| Houstonia ouachitana | (E.B.Sm.) Terrell | 4 | documented |
| Houstonia parviflora | Holz. ex Greenm. | 4 | documented |
| Houstonia correllii | (W.H.Lewis) Terrell | 0 | below the evidence gate |
| Houstonia croftiae | Britton & Rusby | 0 | below the evidence gate |
| Houstonia macvaughii | (Terrell) Govaerts ex Borhidi | 0 | below the evidence gate |
| Houstonia palmeri | A.Gray | 0 | below the evidence gate |
| Houstonia prostrata | Brandegee | 0 | below the evidence gate |
| Houstonia sharpii | Terrell | 0 | below the evidence gate |
| Houstonia spellenbergii | (G.L.Nesom & Vorobik) Terrell | 0 | below the evidence gate |
| Houstonia teretifolia | Terrell | 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.