Pellaea


Penthorum
sedoides


Persicaria
sp_Kawagoeanum
sp_Sao_Paulo


Philydrum
lanuginosum


Phyllanthus
fluitans


Physostegia
purpurea

Pilularia
americana


Pistia
stratiotes


Plagiochila


Podostemum
ceratophyllum
sp_Vietnam_nano

Only one species, P. ceratophyllum found in North America.



Polygonum
barbatum
maharastransii


Polypleurum



Prionium
serratum


Proserpinaca
palustris

"Mermaid weed"