is a species of plant in the class Florideophyceae in the family Rhodomelaceae and order Ceramiales.
Polysiphonia acuminata
Polysiphonia aquamara
Polysiphonia bajacali
Polysiphonia beandetti
Polysiphonia binneyi
Polysiphonia brodiaei
Polysiphonia californica
Polysiphonia carettia
Polysiphonia confusa
Polysiphonia decussata
Polysiphonia denudata
Polysiphonia elongata
Polysiphonia farlowii
Polysiphonia fastigiata
Polysiphonia ferulacea
Polysiphonia fibrillosa
Polysiphonia flaccidissima
Polysiphonia flexicaulis
Polysiphonia hancocki
Polysiphonia harveyi
Polysiphonia havanensis
Polysiphonia hendryi
Polysiphonia homoia
Polysiphonia howei
Polysiphonia indigena
Polysiphonia insidiosa
Polysiphonia johnstonii
Polysiphonia macrocarpa
Polysiphonia minutissima
Polysiphonia mollis
Polysiphonia nathaniellii
Polysiphonia nigra
Polysiphonia nigrescens
Polysiphonia novae-angliae
Polysiphonia pacifica
Polysiphonia paniculata
Polysiphonia pentamera
Polysiphonia savatieri
Polysiphonia scopulorum
Polysiphonia setacea
Polysiphonia simplex
Polysiphonia simulans
Polysiphonia snyderae
Polysiphonia sphaerocarpa
Polysiphonia spinulosa
Polysiphonia subtilissima
Polysiphonia tenuistrata
Polysiphonia tepida
Polysiphonia upolensis
Polysiphonia urceolata
Polysiphonia violacea
Polysiphonia yonakuniensis