| Symbol | Scientific name | Common name/Accepted name (for synonyms) | Family |
| PETIP | Pedilanthus tithymaloides (L.) Poit. ssp. padifolius (L.) Dressler | redbird flower | Euphorbiaceae
|
| PETIP2 | Pedilanthus tithymaloides (L.) Poit. ssp. parasiticus (Klotzsch & Garcke) Dressler | redbird flower | Euphorbiaceae
|
| PETIS | Pedilanthus tithymaloides (L.) Poit. ssp. smallii (Millsp.) Dressler | Small's redbird flower | Euphorbiaceae
|
| PETIT2 | Pedilanthus tithymaloides (L.) Poit. ssp. tithymaloides | redbird flower | Euphorbiaceae
|
| PETIA2 | Pedilanthus tithymaloides (L.) Poit. var. angustifolius (Poit.) Griseb. | Pedilanthus tithymaloides ssp. angustifolius | Euphorbiaceae
|
| PETI | Pedilanthus tithymaloides (L.) Poit. | redbird flower | Euphorbiaceae
|
| PEDIL | Pedilanthus Neck. ex Poit. | pedilanthus | Euphorbiaceae
|
| PEIN16 | Pedinophyllum interruptum (Nees) Kaal. | | Plagiochilaceae
|
| PEDIN | Pedinophyllum (Lindb.) Lindb. | | Plagiochilaceae
|
| PEBR2 | Pediocactus bradyi L. Benson | Brady's hedgehog cactus | Cactaceae
|
| PEDE17 | Pediocactus despainii Welsh & Goodrich | Despain's pincushion cactus | Cactaceae
|
| PEGL14 | Pediocactus glaucus (J.A. Purpus ex K. Schum.) Arp | Sclerocactus glaucus | Cactaceae
|
| PEKN2 | Pediocactus knowltonii L. Benson | Knowlton's miniature cactus | Cactaceae
|
| PEME13 | Pediocactus mesae-verdae (Boissevain ex Boissevain & C. Davids.) Arp | Sclerocactus mesae-verdae | Cactaceae
|
| PEPA20 | Pediocactus papyracanthus (Engelm.) L. Benson | Sclerocactus papyracanthus | Cactaceae
|
| PEPA5 | Pediocactus paradinei B.W. Benson | park hedgehog cactus | Cactaceae
|
| PEPEF | Pediocactus peeblesianus (Croizat) L. Benson var. fickeiseniae L. Benson | Navajo pincushion cactus | Cactaceae
|
| PEPEP2 | Pediocactus peeblesianus (Croizat) L. Benson var. peeblesianus | Navajo pincushion cactus | Cactaceae
|
| PEPE8 | Pediocactus peeblesianus (Croizat) L. Benson | Navajo pincushion cactus | Cactaceae
|
| PESI4 | Pediocactus sileri (Engelm.) L. Benson | Siler's pincushion cactus | Cactaceae
|
| PESIM | Pediocactus simpsonii (Engelm.) Britt. & Rose var. minor (Engelm.) Cockerell | snowball cactus | Cactaceae
|
| PESIR | Pediocactus simpsonii (Engelm.) Britt. & Rose var. robustior (Coult.) L. Benson | snowball cactus | Cactaceae
|
| PESIS | Pediocactus simpsonii (Engelm.) Britt. & Rose var. simpsonii | Simpson hedgehog cactus | Cactaceae
|
| PESI | Pediocactus simpsonii (Engelm.) Britt. & Rose | Simpson hedgehog cactus | Cactaceae
|
| PEWH5 | Pediocactus whipplei (Engelm. & Bigelow) Arp | Sclerocactus whipplei | Cactaceae
|
| PEWI2 | Pediocactus winkleri Heil | Winkler's pincushion cactus | Cactaceae
|
| PEDIO | Pediocactus Britt. & Rose | hedgehog cactus | Cactaceae
|
| PEAR6 | Pediomelum argophyllum (Pursh) J. Grimes | silverleaf Indian breadroot | Fabaceae
|
| PEARB | Pediomelum aromaticum (Payson) W.A. Weber var. barnebyi Welsh | Pediomelum aromaticum | Fabaceae
|
| PEART | Pediomelum aromaticum (Payson) W.A. Weber var. tuhyi Welsh | Pediomelum aromaticum | Fabaceae
|
| PEAR7 | Pediomelum aromaticum (Payson) W.A. Weber | aromatic Indian breadroot | Fabaceae
|
| PEBR16 | Pediomelum brachypus Rydb. | Pediomelum rhombifolium | Fabaceae
|
| PECA33 | Pediomelum californicum (S. Wats.) Rydb. | California Indian breadroot | Fabaceae
|
| PECA25 | Pediomelum canescens (Michx.) Rydb. | buckroot | Fabaceae
|
| PECA24 | Pediomelum castoreum (S. Wats.) Rydb. | beaver Indian breadroot | Fabaceae
|
| PECO21 | Pediomelum coryi Tharp & Barkl. | Pediomelum rhombifolium | Fabaceae
|
| PECU3 | Pediomelum cuspidatum (Pursh) Rydb. | largebract Indian breadroot | Fabaceae
|
| PECY7 | Pediomelum cyphocalyx (Gray) Rydb. | turniproot | Fabaceae
|
| PEDIP | Pediomelum digitatum (Nutt. ex Torr. & Gray) Isely var. parvifolium (Shinners) Gandhi & L.E. Brown | Pediomelum digitatum | Fabaceae
|
| PEDI9 | Pediomelum digitatum (Nutt. ex Torr. & Gray) Isely | palmleaf Indian breadroot | Fabaceae
|
| PEEP | Pediomelum epipsilum (Barneby) Welsh | Pediomelum megalanthum var. epipsilum | Fabaceae
|
| PEES | Pediomelum esculentum (Pursh) Rydb. | large Indian breadroot | Fabaceae
|
| PEGO3 | Pediomelum goughiae Tharp & Barkl. | Pediomelum hypogaeum var. scaposum | Fabaceae
|
| PEHU6 | Pediomelum humile Rydb. | Rydberg's Indian breadroot | Fabaceae
|
| PEHYH | Pediomelum hypogaeum (Nutt. ex Torr. & Gray) Rydb. var. hypogaeum | subterranean Indian breadroot | Fabaceae
|
| PEHYS | Pediomelum hypogaeum (Nutt. ex Torr. & Gray) Rydb. var. scaposum (Gray) Mahler | subterranean Indian breadroot | Fabaceae
|
| PEHYS2 | Pediomelum hypogaeum (Nutt. ex Torr. & Gray) Rydb. var. subulatum (Bush) J. Grimes | subterranean Indian breadroot | Fabaceae
|
| PEHY4 | Pediomelum hypogaeum (Nutt. ex Torr. & Gray) Rydb. | subterranean Indian breadroot | Fabaceae
|
| PELAA | Pediomelum latestipulatum (Shinners) Mahler var. appressum (D.J. Ockendon) Gandhi & L.E. Brown | Texas Plains Indian breadroot | Fabaceae
|
| PELAL2 | Pediomelum latestipulatum (Shinners) Mahler var. latestipulatum | Texas Plains Indian breadroot | Fabaceae
|
| PELA18 | Pediomelum latestipulatum (Shinners) Mahler | Texas Plains Indian breadroot | Fabaceae
|
| PELI10 | Pediomelum linearifolium (Torr. & Gray) J. Grimes | narrowleaf Indian breadroot | Fabaceae
|
| PEMEE | Pediomelum megalanthum (Woot. & Standl.) Rydb. var. epipsilum (Barneby) J. Grimes | Intermountain Indian breadroot | Fabaceae
|
| PEMEM2 | Pediomelum megalanthum (Woot. & Standl.) Rydb. var. megalanthum | Intermountain Indian breadroot | Fabaceae
|
| PEMER | Pediomelum megalanthum (Woot. & Standl.) Rydb. var. retrorsum (Rydb.) J. Grimes | Intermountain Indian breadroot | Fabaceae
|
| PEME7 | Pediomelum megalanthum (Woot. & Standl.) Rydb. | Intermountain Indian breadroot | Fabaceae
|
| PEME8 | Pediomelum mephiticum (S. Wats.) Rydb. | skunktop | Fabaceae
|
| PEPA41 | Pediomelum pariense (Welsh & Atwood) J. Grimes | Paria River Indian breadroot | Fabaceae
|
| PEPES | Pediomelum pentaphyllum (L.) J. Grimes var. scaposum (Gray) J. Grimes | Pediomelum hypogaeum var. scaposum | Fabaceae
|
| PEPE27 | Pediomelum pentaphyllum (L.) J. Grimes | small Indian breadroot | Fabaceae
|
| PERE10 | Pediomelum reverchonii (S. Wats.) Rydb. | rock Indian breadroot | Fabaceae
|
| PERH2 | Pediomelum rhombifolium (Torr. & Gray) Rydb. | Gulf Indian breadroot | Fabaceae
|
| PESU5 | Pediomelum subacaule (Torr. & Gray) Rydb. | whiterim scurfpea | Fabaceae
|
| PESU11 | Pediomelum subulatum (Bush) Rydb. | Pediomelum hypogaeum var. subulatum | Fabaceae
|
| PETR8 | Pediomelum trinervatum Rydb. | Pediomelum pentaphyllum | Fabaceae
|
| PEDIO2 | Pediomelum Rydb. | Indian breadroot | Fabaceae
|
| PEHA | Peganum harmala L. | harmal peganum | Zygophyllaceae
|
| PEME | Peganum mexicanum Gray | garbancillo | Zygophyllaceae
|
| PEGAN | Peganum L. | peganum | Zygophyllaceae
|
| PEBA8 | Peiranisia bahamensis (P. Mill.) Britt. & Rose ex Britt. & Wilson | Senna ligustrina | Fabaceae
|
| PEPO5 | Peiranisia polyphylla (Jacq.) Britt. & Rose | Senna polyphylla | Fabaceae
|
| PECA13 | Pelargonium capitatum (L.) L'H�r. ex Ait. | rose scented geranium | Geraniaceae
|
| PEDO2 | Pelargonium �domesticum Bailey (pro sp.) | regal pelargonium | Geraniaceae
|
| PEGR11 | Pelargonium graveolens L'H�r. ex Ait. | sweet scented geranium | Geraniaceae
|
| PEGR12 | Pelargonium grossularioides (L.) L'H�r. ex Ait. | gooseberry geranium | Geraniaceae
|
| PEHO2 | Pelargonium �hortorum Bailey (pro sp.) | zonal geranium | Geraniaceae
|
| PEIN6 | Pelargonium inodorum Willd. | scentless geranium | Geraniaceae
|
| PEIN7 | Pelargonium inquinans (L.) L'H�r. ex Ait. | scarlet geranium | Geraniaceae
|
| PEOD | Pelargonium odoratissimum (L.) L'H�r. ex Ait. | apple geranium | Geraniaceae
|
| PEPA52 | Pelargonium panduriforme Ecklon & Zeyh. | oakleaf garden geranium | Geraniaceae
|
| PEPE6 | Pelargonium peltatum (L.) L'H�r. ex Ait. | ivyleaf geranium | Geraniaceae
|
| PEQU5 | Pelargonium quercifolium (L. f.) L'H�r. ex Ait. | oakleaf geranium | Geraniaceae
|
| PERA14 | Pelargonium radens H.E. Moore | rasp-leaf pelargonium | Geraniaceae
|
| PERA13 | Pelargonium radula (Cav.) L'Her | Pelargonium radens | Geraniaceae
|
| PEVI8 | Pelargonium vitifolium (L.) L'H�r. ex Ait. | grapeleaf geranium | Geraniaceae
|
| PEZO | Pelargonium zonale (L.) L'H�r. ex Ait. | horseshoe geranium | Geraniaceae
|
| PELAR2 | Pelargonium L'H�r. ex Ait. | geranium | Geraniaceae
|
| PEAD | Pelea adscendens St. John & Hume | Melicope adscendens | Rutaceae
|
| PEAH | Pelea ahiaensis St. John | Melicope volcanica | Rutaceae
|
| PEAN7 | Pelea anapanapaensis St. John | Melicope volcanica | Rutaceae
|
| PEANH | Pelea anisata Mann var. haupuana B.C. Stone | Melicope anisata | Rutaceae
|
| PEAN8 | Pelea anisata Mann | Melicope anisata | Rutaceae
|
| PEAP | Pelea apoda St. John | Melicope lydgatei | Rutaceae
|
| PEBA3 | Pelea balloui Rock | Melicope balloui | Rutaceae
|
| PEBA4 | Pelea barbigera (Gray) Hbd. | Melicope barbigera | Rutaceae
|
| PECA31 | Pelea cauliflora St. John | Melicope pseudoanisata | Rutaceae
|
| PECH2 | Pelea christophersenii St. John | Melicope christophersenii | Rutaceae
|
| PECIM | Pelea cinerea (Gray) Hbd. var. mauiana B.C. Stone | Melicope cinerea | Rutaceae
|
| PECIS | Pelea cinerea (Gray) Hbd. var. skottsbergii B.C. Stone | Melicope cinerea | Rutaceae
|
| PECI5 | Pelea cinerea (Gray) Hbd. | Melicope cinerea | Rutaceae
|
| PECI6 | Pelea cinereops St. John & Hume | Melicope sandwicensis | Rutaceae
|