Ten Penstemon species compared through exact Wikimedia Commons photographs of flowers and growth forms. An editorial selection, not a scientific ranking. Original video contributions: CC BY-SA 4.0. Individual photographs retain the licences and credits listed in attribution; public-domain and CC0 photographs remain so. Photograph credits: 1. File:Penstemon digitalis.jpg; Eric Hunt; CC BY-SA 4.0; https://creativecommons.org/licenses/by-sa/4.0; https://commons.wikimedia.org/wiki/File%3APenstemon_digitalis.jpg; Whole-image fit and scaling; title and caption bars added. Photograph licensed under the stated source licence. 2. File:Penstemon barbatus - Wendy McCrady 01.jpg; Wendy McCrady https://www.inaturalist.org/people/wendybirds; CC BY 4.0; https://creativecommons.org/licenses/by/4.0; https://commons.wikimedia.org/wiki/File%3APenstemon_barbatus_-_Wendy_McCrady_01.jpg; Portrait crop of the flowering stem, scaling and caption bars. Original photograph retained as images/02.jpg. 3. File:Penstemon eatonii 3.jpg; Stan Shebs; CC BY-SA 3.0; https://creativecommons.org/licenses/by-sa/3.0; https://commons.wikimedia.org/wiki/File%3APenstemon_eatonii_3.jpg; Whole-image fit and scaling; title and caption bars added. Photograph licensed under the stated source licence. 4. File:Penstemon strictus - Todd Boland 01.jpg; Todd Boland https://www.inaturalist.org/people/todd_boland; CC BY 4.0; https://creativecommons.org/licenses/by/4.0; https://commons.wikimedia.org/wiki/File%3APenstemon_strictus_-_Todd_Boland_01.jpg; Whole-image fit and scaling; title and caption bars added. Photograph licensed under the stated source licence. 5. File:Penstemon grandiflorus - Evan Grimes 01.jpg; Evan Grimes https://www.inaturalist.org/people/evangrimes; CC BY 4.0; https://creativecommons.org/licenses/by/4.0; https://commons.wikimedia.org/wiki/File%3APenstemon_grandiflorus_-_Evan_Grimes_01.jpg; Whole-image fit and scaling; title and caption bars added. Photograph licensed under the stated source licence. 6. File:Penstemon palmeri 5.jpg; Stan Shebs; CC BY-SA 3.0; https://creativecommons.org/licenses/by-sa/3.0; https://commons.wikimedia.org/wiki/File%3APenstemon_palmeri_5.jpg; Whole-image fit and scaling; title and caption bars added. Photograph licensed under the stated source licence. 7. File:Penstemon pinifolius - Patrick Alexander 01.jpg; Patrick Alexander https://www.inaturalist.org/people/aspidoscelis; CC0; http://creativecommons.org/publicdomain/zero/1.0/deed.en; https://commons.wikimedia.org/wiki/File%3APenstemon_pinifolius_-_Patrick_Alexander_01.jpg; Whole-image fit and scaling; title and caption bars added. Photograph licensed under the stated source licence. 8. File:Penstemonheterophyllus0.jpg; Stickpen; Public domain; ; https://commons.wikimedia.org/wiki/File%3APenstemonheterophyllus0.jpg; Whole-image fit and scaling; title and caption bars added. Photograph licensed under the stated source licence. 9. File:Penstemonspectabilis.jpg; Stickpen; Public domain; ; https://commons.wikimedia.org/wiki/File%3APenstemonspectabilis.jpg; Whole-image fit and scaling; title and caption bars added. Photograph licensed under the stated source licence. 10. File:Hairy Beard-tongue, PE Cty.jpg; D. Gordon E. Robertson; CC BY-SA 3.0; https://creativecommons.org/licenses/by-sa/3.0; https://commons.wikimedia.org/wiki/File%3AHairy_Beard-tongue%2C_PE_Cty.jpg; Whole-image fit and scaling; title and caption bars added. Photograph licensed under the stated source licence.