All Species in Isoetes
- Acadian Quillwort (Isoetes tuckermanii subsp. acadiensis)
- Appalachian Quillwort (Isoetes appalachiana)
- Appalachian Quillwort (Isoetes engelmannii)
- Big-Spore Quillwort (Isoetes macrospora)
- Blackfoot Quillwort (Isoetes melanopoda)
- Blackspore Quillwort (Isoetes melanospora)
- Bolander's Quillwort (Isoetes bolanderi)
- Boom's Quillwort (Isoetes boomii)
- Evergreen Quillwort (Isoetes hyemalis)
- Georgia Quillwort (Isoetes georgiana)
- Hawai'I Quillwort (Isoetes hawaiiensis)
- Howell's Quillwort (Isoetes howellii)
- Lake Quillwort (Isoetes lacustris)
- Limestone Quillwort (Isoetes butleri)
- Louisiana Quillwort (Isoetes louisianensis)
- Maritime Quillwort (Isoetes maritima)
- Mattaponi Quillwort (Isoetes mattaponica)
- Midget Quillwort (Isoetes minima)
- Nuttall's Quillwort (Isoetes nuttallii)
- Orcutt's Quillwort (Isoetes orcuttii)
- Peidmont Quillwort (Isoetes piedmontana)
- Quillwort (Isoetes × brittonii)
- Quillwort (Isoetes × bruntonii)
- Quillwort (Isoetes × dodgei)
- Quillwort (Isoetes × fairbrothersii)
- Quillwort (Isoetes × foveolata)
- Quillwort (Isoetes × harveyi)
- Quillwort (Isoetes × herb-wagneri)
- Quillwort (Isoetes × hickeyi)
- Quillwort (Isoetes ×altonharvillii)
- Quillwort (Isoetes ×eatonii)
- Quillwort (Isoetes ×echtuckeri)
- Quillwort (Isoetes truncata)
- Rock Quillwort (Isoetes lithophila)
- Rush Quillwort (Isoetes junciformis)
- Shore Quillwort (Isoetes riparia)
- Southern Quillwort (Isoetes flaccida)
- Spike Quillwort (Isoetes prototypus)
- Spiny-Spore Quillwort (Isoetes tenella)
- Strong Quillwort (Isoetes valida)
- Sugar Quillwort (Isoetes riparia f. saccharata)
- Taylor's Quillwort (Isoetes × carltaylorii)
- Tennessee Quillwort (Isoetes tennesseensis)
- Texas Quillwort (Isoetes texana)
- Thin-Wall Quillwort (Isoetes microvela)
- Tuckerman's Quillwort (Isoetes tuckermanii)
- Virginia Quillwort (Isoetes melanopoda subsp. melanopoda)
- Western Quillwort (Isoetes occidentalis)