Plectofusulina franklinensis
Plectofusulina fusiformis
Plectofusulina rotunda
Pleotrichophorus pseudoglandulosus
Plesiocystis pacifica
Nannocystaceae
Poa glauca
Greenland Bluegrass — Poaceae > Poales > Magnoliopsida
Poa gracilis
Poa gunni
Poa palustris
Fowl Bluegrass — Poaceae > Poales > Magnoliopsida
Poa secunda
Sandberg bluegrass — Poaceae > Poales > Magnoliopsida
Pogogyne abramsii
Mesa Mint, San Diego — Lamiaceae > Lamiales > Magnoliopsida
Polygonum aviculare
Devils Shoestrings — Polygonaceae > Caryophyllales > Magnoliopsida
Polygonum cuspidatum
Populus deltoides
cottonwood — Salicaceae > Malpighiales > Magnoliopsida
Populus species
cottonwoods —
Potentilla anserina ssp. anserina
silver leaf — Rosaceae > Rosales > Magnoliopsida
Potentilla hippiana × gracilis
Potentilla rubricaulis
Red-stem Cinquefoil — Rosaceae > Rosales > Magnoliopsida
Precis coenia
Preromalus
Primula florindae
Prosimulium exigens
Simuliidae > Diptera > Insecta
Prosimulium fulvum
Simuliidae > Diptera > Insecta
Prosimulium hirtipes
Simuliidae > Diptera > Insecta
Prosimulium uinta
Simuliidae
Proxylocopa olivieri
Prunus persica
peaches — Rosaceae > Rosales > Magnoliopsida
Prunus serotina
Rosaceae > Rosales > Magnoliopsida
Pseudacaudella pseudoglandulosus
Pseudomonas GM17
Pseudomonas GM30
Pseudomonas GM41
Pseudomonas fluorescens GM30
Pseudomonas fluorescens GM41
Pseudostaffella needhami
Pseudowedekindellina
Psiloscops flammeolus
Flammulated owl — Strigidae > Strigiformes > Aves
Pulsatilla patens
Pasqueflower — Ranunculaceae
Purshia tridentata
antelope bitterbrush — Rosaceae > Rosales > Magnoliopsida
Pyrus communis
pear — Rosaceae > Rosales > Magnoliopsida
Quercus aquifolioides
Quercus gambelii
Fagaceae > Fagales > Magnoliopsida
Quercus guyavifolia
alpine oak — Fagaceae
Quercus liaotungensis
Quercus velutina
Fagaceae > Fagales > Magnoliopsida
R. ferrugineum
R. subarcticum
RNA
ribonucleic acid —
Radium 226
Ranunculus alismifolius
Plantainleaf Buttercup — Ranunculaceae > Ranunculales > Magnoliopsida