| Symbol | Scientific name | Common name/Accepted name (for synonyms) | Family |
| PYSE2 | Pycnanthemum setosum Nutt. | awned mountainmint | Lamiaceae
|
| PYTE | Pycnanthemum tenuifolium Schrad. | narrowleaf mountainmint | Lamiaceae
|
| PYTOL | Pycnanthemum torrei Benth. var. leptodon (Gray) Boomhour | Pycnanthemum verticillatum var. verticillatum | Lamiaceae
|
| PYTO | Pycnanthemum torrei Benth. | Torrey's mountainmint | Lamiaceae
|
| PYTU | Pycnanthemum tullium Benth. | Pycnanthemum pycnanthemoides var. viridifolium | Lamiaceae
|
| PYUM | Pycnanthemum umbratile Fern. | Pycnanthemum setosum | Lamiaceae
|
| PYVEP | Pycnanthemum verticillatum (Michx.) Pers. var. pilosum (Nutt.) Cooperrider | whorled mountainmint | Lamiaceae
|
| PYVEV | Pycnanthemum verticillatum (Michx.) Pers. var. verticillatum | whorled mountainmint | Lamiaceae
|
| PYVE | Pycnanthemum verticillatum (Michx.) Pers. | whorled mountainmint | Lamiaceae
|
| PYVIV | Pycnanthemum virginianum (L.) T. Dur. & B.D. Jackson ex B.L. Robins. & Fern. var. verticillatum (Michx.) Boivin | Pycnanthemum verticillatum var. verticillatum | Lamiaceae
|
| PYVI | Pycnanthemum virginianum (L.) T. Dur. & B.D. Jackson ex B.L. Robins. & Fern. | Virginia mountainmint | Lamiaceae
|
| PYVI2 | Pycnanthemum viridifolium (Fern.) E. Grant & Epling | Pycnanthemum pycnanthemoides var. viridifolium | Lamiaceae
|
| PYCNA | Pycnanthemum Michx. | mountainmint | Lamiaceae
|
| PYPA3 | Pycnothelia papillaria Dufour | | Cladoniaceae
|
| PYCNO2 | Pycnothelia Dufour | pycnothelia | Cladoniaceae
|
| PYRI | Pycnothymus rigidus (Bartr. ex Benth.) Small | Piloblephis rigida | Lamiaceae
|
| PYFL3 | Pycreus flavescens (L.) Reichenb. | Cyperus flavescens | Cyperaceae
|
| PYFL6 | Pycreus flavicomus (Michx.) C.D. Adams | Cyperus flavicomus | Cyperaceae
|
| PYNI | Pycreus niger (Ruiz & Pav�n) Cufod. | Cyperus niger | Cyperaceae
|
| PYPOH | Pycreus polystachyos (Rottb.) Beauv. ssp. holosericeus (Link) T. Koyama | Cyperus polystachyos var. texensis | Cyperaceae
|
| PYPO | Pycreus polystachyos (Rottb.) Beauv. | Cyperus polystachyos var. polystachyos | Cyperaceae
|
| PYRI2 | Pycreus rivularis (Kunth) Palla | Cyperus bipartitus | Cyperaceae
|
| PYSA | Pycreus sanguindentus (Vahl) Nees | Cyperus sanguindentus | Cyperaceae
|
| PYUN3 | Pycreus unioloides (R. Br.) C.B. Clarke | Cyperus unioloides | Cyperaceae
|
| PYHE2 | Pylaisia heteromalla Bruch & Schimp. | Pylaisiella polyantha | Hypnaceae
|
| PYIN5 | Pylaisia intricata (Hedw.) Schimp. in B.S.G. | Pylaisiella intricata | Hypnaceae
|
| PYJA3 | Pylaisia jamesii Sull. & Lesq. | Pylaisiella polyantha | Hypnaceae
|
| PYON | Pylaisia ontariensis C. M�ll. & Kindb. in Mac. & Kindb. | Pylaisiella polyantha | Hypnaceae
|
| PYPOB | Pylaisia polyantha (Hedw.) Schimp. in B.S.G. var. brevifolia (Lindb. & Arnell) Limpr. | Pylaisiella polyantha | Hypnaceae
|
| PYPOJ | Pylaisia polyantha (Hedw.) Schimp. in B.S.G. var. jamesii (Sull. & Lesq.) Rau & Herv. | Pylaisiella polyantha | Hypnaceae
|
| PYPOP | Pylaisia polyantha (Hedw.) Schimp. in B.S.G. var. pseudoplatygyria (Kindb.) Grout | Pylaisiella polyantha | Hypnaceae
|
| PYPO4 | Pylaisia polyantha (Hedw.) Schimp. in B.S.G. | Pylaisiella polyantha | Hypnaceae
|
| PYSC3 | Pylaisia schimperi Card. | Pylaisiella selwynii | Hypnaceae
|
| PYSE8 | Pylaisia selwynii Kindb. | Pylaisiella selwynii | Hypnaceae
|
| PYSU7 | Pylaisia subdenticulata Schimp. in B.S.G. | Pylaisiella polyantha | Hypnaceae
|
| PYVE3 | Pylaisia velutina Schimp. in B.S.G. | Pylaisiella intricata | Hypnaceae
|
| PYRE2 | Pylaisiadelpha recurvans (Michx.) Buck | Brotherella recurvans | Sematophyllaceae
|
| PYRO3 | Pylaisiadelpha roellii (Ren. & Card. in R�ll) Buck | Brotherella roellii | Sematophyllaceae
|
| PYTE4 | Pylaisiadelpha tenuirostris (Bruch & Schimp. ex Sull.) Buck | pylaisiadelpha moss | Hypnaceae
|
| PYLAI | Pylaisiadelpha Card. | pylaisiadelpha moss | Hypnaceae
|
| PYIN4 | Pylaisiella intricata (Hedw.) Grout | intricate pylaisiella moss | Hypnaceae
|
| PYPO3 | Pylaisiella polyantha (Hedw.) Grout | pylaisiella moss | Hypnaceae
|
| PYSE7 | Pylaisiella selwynii (Kindb.) Crum et al. | Selwyn's pylaisiella moss | Hypnaceae
|
| PYST2 | Pylaisiella steerei Ando & Higuchi | Steere's pylaisiella moss | Hypnaceae
|
| PYLAI2 | Pylaisiella Kindb. | pylaisiella moss | Hypnaceae
|
| PYAR4 | Pylostachya arenicola Small | Polygala smallii | Polygalaceae
|
| PYBA2 | Pylostachya balduinii (Nutt.) Small | Polygala balduinii var. balduinii | Polygalaceae
|
| PYCA4 | Pylostachya carteri (Small) Small | Polygala balduinii var. carteri | Polygalaceae
|
| PYCY | Pylostachya cymosa (Walt.) Small | Polygala cymosa | Polygalaceae
|
| PYLU2 | Pylostachya lutea (L.) Small | Polygala lutea | Polygalaceae
|
| PYNA | Pylostachya nana (Michx.) Raf. | Polygala nana | Polygalaceae
|
| PYRA3 | Pylostachya ramosa (Ell.) Small | Polygala ramosa | Polygalaceae
|
| PYRU | Pylostachya rugelii (Shuttlw. ex Chapman) Small | Polygala rugelii | Polygalaceae
|
| PYAN | Pyracantha angustifolia (Franch.) Schneid. | narrowleaf firethorn | Rosaceae
|
| PYCO2 | Pyracantha coccinea M. Roemer | scarlet firethorn | Rosaceae
|
| PYCR | Pyracantha crenatiserrata (Hance) Rehd. | Pyracantha fortuneana | Rosaceae
|
| PYCR7 | Pyracantha crenulata (D. Don) Roemer | | Rosaceae
|
| PYFO | Pyracantha fortuneana (Maxim.) Li | Chinese firethorn | Rosaceae
|
| PYKO | Pyracantha koidzumii (Hayata) Rehd. | Formosa firethorn | Rosaceae
|
| PYRAC | Pyracantha M. Roemer | firethorn | Rosaceae
|
| PYTE5 | Pyramidula tetragona (Brid.) Brid. | pyramid moss | Funariaceae
|
| PYRAM | Pyramidula Brid. | pyramid moss | Funariaceae
|
| PYCU4 | Pyrenastrum cubanum Mull. Arg. | Pyrenula cubana | Pyrenulaceae
|
| PYFU5 | Pyrenastrum fuscum Mont. | Pyrenula septicollaris | Pyrenulaceae
|
| PYPY4 | Pyrenastrum pyrenastraeum (Nyl.) Zahlbr. | Pyrenula septicollaris | Pyrenulaceae
|
| PYHY3 | Pyrenidium hyalosporum Alstrup,D. Hawksw. & R. Sant. | | Dacampiaceae
|
| PYOC5 | Pyrenidium octosporum Looman | Chromatochlamys muscorum var. octospora | Thelenellaceae
|
| PYREN | Pyrenidium Nyl. | pyrenidium | Dacampiaceae
|
| PYAC2 | Pyrenidum actinellum Nyl. | | Dacampiaceae
|
| PYREN6 | Pyrenidum Nyl. | pyrenidum | Dacampiaceae
|
| PYAT | Pyrenocollema atlanticum (Vainio) R. C. Harris | | Pyrenulaceae
|
| PYCA7 | Pyrenocollema caesium (Nyl.) R. C. Harris | | Pyrenulaceae
|
| PYEL4 | Pyrenocollema elegans R. Sant. | | Pyrenulaceae
|
| PYHA | Pyrenocollema halodytes (Nyl.) R. C. Harris | | Pyrenulaceae
|
| PYPR2 | Pyrenocollema prospersellum (Nyl.) R. C. Harris | | Pyrenulaceae
|
| PYST | Pyrenocollema strontianensis (Swinscow) R. C. Harris | | Pyrenulaceae
|
| PYSU8 | Pyrenocollema sublitorale (Leighton) R. C. Harris ex Fletcher | | Pyrenulaceae
|
| PYTI | Pyrenocollema tichothecioides (Arnold) R. C. Harris | | Pyrenulaceae
|
| PYREN2 | Pyrenocollema Reinke | pyrenocollema | Pyrenulaceae
|
| PYAL4 | Pyrenodesmia albovariegata de Lesd. | Caloplaca albovariegata | Teloschistaceae
|
| PYEL3 | Pyrenodesmia elaeodes E. D. Rudolph | Caloplaca pelodella | Teloschistaceae
|
| PYMO3 | Pyrenodesmia montana de Lesd. | Caloplaca montana | Teloschistaceae
|
| PYGR4 | Pyrenopsidium granuliforme (Nyl.) Forss. | Cryptothele granuliformis | Lichinaceae
|
| PYHO | Pyrenopsidium homoeopsis (Nyl.) Forss. | Pyrenopsis furfurea | Lichinaceae
|
| PYCO8 | Pyrenopsis compacta Willey | | Lichinaceae
|
| PYFU2 | Pyrenopsis furfurea (Nyl.) Th. Fr. | | Lichinaceae
|
| PYFU3 | Pyrenopsis fuscoatra Fink | | Lichinaceae
|
| PYGR5 | Pyrenopsis granatina (Sommerf.) Nyl. | Euopsis granatina | Lichinaceae
|
| PYGR3 | Pyrenopsis grumulifera Nyl. | | Lichinaceae
|
| PYHA2 | Pyrenopsis haemalella (Nyl.) Blomb. & Forss. | | Lichinaceae
|
| PYHO2 | Pyrenopsis homoeopsis Nyl. | Pyrenopsis furfurea | Lichinaceae
|
| PYLE2 | Pyrenopsis lecidella Fink | | Lichinaceae
|
| PYME2 | Pyrenopsis melambola (Tuck.) Tuck. | Metamelaena melambola | Lichinaceae
|
| PYMU3 | Pyrenopsis multispora E. Dahl | Pyrenopsis grumulifera | Lichinaceae
|
| PYMY | Pyrenopsis myriospora E. Dahl | Pyrenopsis grumulifera | Lichinaceae
|
| PYPH | Pyrenopsis phaeococca Tuck. | | Lichinaceae
|
| PYPH2 | Pyrenopsis phylliscina (Tuck.) Tuck. | Cryptothele permiscens | Lichinaceae
|
| PYPO2 | Pyrenopsis polycocca (Nyl.) Tuck. | | Lichinaceae
|
| PYPU5 | Pyrenopsis pulvinata (Schaerer) Th. Fr. | Euopsis pulvinata | Lichinaceae
|
| PYSA2 | Pyrenopsis sanguinea Anzi | | Lichinaceae
|
| PYSC2 | Pyrenopsis schaereri A. Massal. | Psorotichia schaereri | Lichinaceae
|