| Symbol | Scientific name | Common name/Accepted name (for synonyms) | Family |
| PESU19 | Pertusaria subpertusa Brodo | pore lichen | Pertusariaceae
|
| PESU21 | Pertusaria subplicans Nyl. | Ochrolechia subplicans ssp. subplicans | Pertusariaceae
|
| PESU22 | Pertusaria subpupillaris Vezda | Pertusaria glaucomela | Pertusariaceae
|
| PESU20 | Pertusaria sulcata Dibben | pore lichen | Pertusariaceae
|
| PETA | Pertusaria tabuliformis Erichsen | Pertusaria leioplaca | Pertusariaceae
|
| PETA2 | Pertusaria taeniata Erichsen | Pertusaria zeorina | Pertusariaceae
|
| PETE18 | Pertusaria tetrathalamia (Fee) Nyl. | pore lichen | Pertusariaceae
|
| PETE19 | Pertusaria texana Mull. Arg. | Texan pore lichen | Pertusariaceae
|
| PETO7 | Pertusaria torquata Mull. Arg. | Pertusaria propinqua | Pertusariaceae
|
| PETR12 | Pertusaria trachydactyla Vainio | Ochrolechia trachydactyla | Pertusariaceae
|
| PETR10 | Pertusaria trachythallina Erichsen | pore lichen | Pertusariaceae
|
| PETR11 | Pertusaria trochisea Norman | pore lichen | Pertusariaceae
|
| PETU5 | Pertusaria tuckermanii Erichsen | Pertusaria subobducens | Pertusariaceae
|
| PEVA4 | Pertusaria valliculata Dibben | pore lichen | Pertusariaceae
|
| PEVE7 | Pertusaria velata (Turner) Nyl. | pore lichen | Pertusariaceae
|
| PEVE8 | Pertusaria ventosa Malme | pore lichen | Pertusariaceae
|
| PEVI17 | Pertusaria virensica R. C. Harris | pore lichen | Pertusariaceae
|
| PEWA16 | Pertusaria waghornei Hulting | Waghorne's pore lichen | Pertusariaceae
|
| PEWU2 | Pertusaria wulfenii DC. | Pertusaria hymenea | Pertusariaceae
|
| PEWU | Pertusaria wulfenioides de Lesd. | Wulfen's pore lichen | Pertusariaceae
|
| PEXA | Pertusaria xanthodes Mull. Arg. | pore lichen | Pertusariaceae
|
| PEXA2 | Pertusaria xanthostoma (Sommerf.) Fr. | Ochrolechia xanthostoma | Pertusariaceae
|
| PEZE | Pertusaria zeorina Erichsen | pore lichen | Pertusariaceae
|
| PERTU | Pertusaria DC. | pore lichen | Pertusariaceae
|
| PEBI3 | Perularia bidentata (Ell.) Small | Platanthera flava var. flava | Orchidaceae
|
| PEFL13 | Perularia flava (L.) Farw. | Platanthera flava var. flava | Orchidaceae
|
| PESC7 | Perularia scutellata (Nutt.) Small | Platanthera flava var. flava | Orchidaceae
|
| PEGI3 | Petalonyx gilmanii Munz | Petalonyx thurberi ssp. gilmanii | Loasaceae
|
| PELI5 | Petalonyx linearis Greene | narrowleaf sandpaper plant | Loasaceae
|
| PENI | Petalonyx nitidus S. Wats. | shinyleaf sandpaper plant | Loasaceae
|
| PEPA13 | Petalonyx parryi Gray | Parry's sandpaper plant | Loasaceae
|
| PETHG | Petalonyx thurberi Gray ssp. gilmanii (Munz) Davis & H.J. Thompson | Death Valley sandpaper plant | Loasaceae
|
| PETHT | Petalonyx thurberi Gray ssp. thurberi | Thurber's sandpaper plant | Loasaceae
|
| PETHG2 | Petalonyx thurberi Gray var. gilmanii (Munz) L. Benson | Petalonyx thurberi ssp. gilmanii | Loasaceae
|
| PETH4 | Petalonyx thurberi Gray | Thurber's sandpaper plant | Loasaceae
|
| PETAL | Petalonyx Gray | sandpaper plant | Loasaceae
|
| PERA11 | Petalophyllum ralfsii (Wilson) Nees & Gottsche ex Lehm. | | Fossombroniaceae
|
| PETAL3 | Petalophyllum Nees & Gottsche ex Lehm. | | Fossombroniaceae
|
| PEAD2 | Petalostemon adenopodus (Rydb.) Wemple | Dalea adenopoda | Fabaceae
|
| PEAL13 | Petalostemon albidus (Torr. & Gray) Small | Dalea carnea var. albida | Fabaceae
|
| PEAR9 | Petalostemon arenicola Wemple | Dalea purpurea var. arenicola | Fabaceae
|
| PECAO | Petalostemon candidus Michx. var. oligophyllus (Torr.) F.J. Herm. | Dalea candida var. oligophylla | Fabaceae
|
| PECA21 | Petalostemon candidus Michx. | Dalea candida var. candida | Fabaceae
|
| PECA22 | Petalostemon carneus Michx. | Dalea carnea var. carnea | Fabaceae
|
| PECA23 | Petalostemon caroliniensis (Lam.) Sprague | Dalea pinnata var. pinnata | Fabaceae
|
| PECO28 | Petalostemon compactus (Spreng.) Swezey | Dalea compacta var. compacta | Fabaceae
|
| PEDE20 | Petalostemon decumbens Nutt. | Dalea compacta var. compacta | Fabaceae
|
| PEEM4 | Petalostemon emarginatus Torr. & Gray | Dalea emarginata | Fabaceae
|
| PEEX3 | Petalostemon exilis Gray | Dalea exigua | Fabaceae
|
| PEFE5 | Petalostemon feayi Chapman | Dalea feayi | Fabaceae
|
| PEFL9 | Petalostemon flavescens S. Wats. | Dalea flavescens | Fabaceae
|
| PEFO5 | Petalostemon foliosus Gray | Dalea foliosa | Fabaceae
|
| PEGA6 | Petalostemon gattingeri (Heller) Heller | Dalea gattingeri | Fabaceae
|
| PEGL15 | Petalostemon glandulosus Coult. & Fisher | Dalea phleoides var. phleoides | Fabaceae
|
| PEGR17 | Petalostemon gracilis Nutt. | Dalea carnea var. gracilis | Fabaceae
|
| PEGR19 | Petalostemon griseus Torr. & Gray | Dalea villosa var. grisea | Fabaceae
|
| PEMA21 | Petalostemon macrostachyus Torr. | Dalea cylindriceps | Fabaceae
|
| PEMI14 | Petalostemon microphyllus (Torr. & Gray) Heller | Dalea phleoides var. microphylla | Fabaceae
|
| PEMO9 | Petalostemon mollis Rydb. | Dalea purpurea var. purpurea | Fabaceae
|
| PEMU12 | Petalostemon multiflorus Nutt. | Dalea multiflora | Fabaceae
|
| PEOB5 | Petalostemon obovatus Torr. & Gray | Dalea obovata | Fabaceae
|
| PEOC2 | Petalostemon occidentalis (Heller) Fern. | Dalea candida var. oligophylla | Fabaceae
|
| PEOL3 | Petalostemon oligophyllus (Torr.) Torr. ex Smyth | Dalea candida var. oligophylla | Fabaceae
|
| PEOR7 | Petalostemon ornatus Dougl. ex Hook. | Dalea ornata | Fabaceae
|
| PEPHM | Petalostemon phleoides Torr. & Gray var. microphyllus (Torr. & Gray) Barneby | Dalea phleoides var. microphylla | Fabaceae
|
| PEPH3 | Petalostemon phleoides Torr. & Gray | Dalea phleoides var. phleoides | Fabaceae
|
| PEPI6 | Petalostemon pilosulus Rydb. | Dalea albiflora | Fabaceae
|
| PEPIT | Petalostemon pinnatus (J.F. Gmel.) Blake ssp. trifoliatus (Chapman) Wemple | Dalea pinnata var. trifoliata | Fabaceae
|
| PEPI5 | Petalostemon pinnatus (J.F. Gmel.) Blake | Dalea pinnata var. pinnata | Fabaceae
|
| PEPR8 | Petalostemon prostratus Woot. & Standl. | Dalea scariosa | Fabaceae
|
| PEPU3 | Petalostemon pulcherrimus (Heller) Heller | Dalea compacta var. pubescens | Fabaceae
|
| PEPUM | Petalostemon purpureus (Vent.) Rydb. var. mollis (Rydb.) Boivin | Dalea purpurea var. purpurea | Fabaceae
|
| PEPU15 | Petalostemon purpureus (Vent.) Rydb. | Dalea purpurea var. purpurea | Fabaceae
|
| PERE9 | Petalostemon reverchonii S. Wats. | Dalea reverchonii | Fabaceae
|
| PESA14 | Petalostemon sabinalis S. Wats. | Dalea sabinalis | Fabaceae
|
| PESC6 | Petalostemon scariosus (S. Wats.) Wemple | Dalea scariosa | Fabaceae
|
| PESE14 | Petalostemon searlsiae Gray | Dalea searlsiae | Fabaceae
|
| PEST10 | Petalostemon stanfieldii Small | Dalea tenuis | Fabaceae
|
| PETE16 | Petalostemon tenuifolius Gray | Dalea tenuifolia | Fabaceae
|
| PETE13 | Petalostemon tenuis (Coult.) Heller | Dalea tenuis | Fabaceae
|
| PEVI12 | Petalostemon villosus Nutt. | Dalea villosa var. villosa | Fabaceae
|
| PEAL16 | Petasites alaskanus Rydb. | Petasites frigidus var. frigidus | Asteraceae
|
| PEAR5 | Petasites arcticus Porsild | Petasites frigidus var. palmatus | Asteraceae
|
| PECO24 | Petasites corymbosus (R. Br.) Rydb. | Petasites frigidus var. frigidus | Asteraceae
|
| PEDE19 | Petasites dentatus Blank. | Petasites sagittatus | Asteraceae
|
| PEFRA3 | Petasites frigidus (L.) Fries ssp. arcticus (Porsild) Cody | Petasites frigidus var. palmatus | Asteraceae
|
| PEFRN2 | Petasites frigidus (L.) Fries ssp. nivalis (Greene) Cody | Petasites frigidus var. nivalis | Asteraceae
|
| PEFRP2 | Petasites frigidus (L.) Fries ssp. palmatus (Ait.) Cody | Petasites frigidus var. palmatus | Asteraceae
|
| PEFRC | Petasites frigidus (L.) Fries var. corymbosus (R. Br.) Cronq. | Petasites frigidus var. frigidus | Asteraceae
|
| PEFRF | Petasites frigidus (L.) Fries var. frigidus | arctic sweet coltsfoot | Asteraceae
|
| PEFRH | Petasites frigidus (L.) Fries var. hyperboreoides Hult�n | Petasites frigidus var. frigidus | Asteraceae
|
| PEFRN | Petasites frigidus (L.) Fries var. nivalis (Greene) Cronq. | arctic sweet coltsfoot | Asteraceae
|
| PEFRP | Petasites frigidus (L.) Fries var. palmatus (Ait.) Cronq. | arctic sweet coltsfoot | Asteraceae
|
| PEFR5 | Petasites frigidus (L.) Fries | arctic sweet coltsfoot | Asteraceae
|
| PEGR18 | Petasites gracilis Britt. | Petasites frigidus var. frigidus | Asteraceae
|
| PEHO7 | Petasites hookerianus (Nutt.) Rydb. | Petasites frigidus var. palmatus | Asteraceae
|
| PEHY | Petasites hybridus (L.) P.G. Gaertn., B. Mey. & Scherb. | pestilence wort | Asteraceae
|
| PEHY5 | Petasites hyperboreus Rydb. | Petasites frigidus var. nivalis | Asteraceae
|
| PEJA3 | Petasites japonicus (Sieb. & Zucc.) Maxim. | Japanese sweet coltsfoot | Asteraceae
|
| PENIV | Petasites nivalis Greene ssp. vitifolius (Greene) Toman | Petasites vitifolius | Asteraceae
|
| PENI4 | Petasites nivalis Greene | Petasites frigidus var. nivalis | Asteraceae
|