According to the information of The Plant List database (as of July 2016), the genus includes 84 species [1] :
- Isoetes acadiensis Kott
- Isoetes aequinoctialis A. Braun
- Isoetes amazonica A. Braun
- Isoetes andicola ( Amstutz ) LD Gómez
- Isoetes andina Spruce ex Hook.
- Isoetes appalachiana df brunt. DM Britton
- Isoetes asiatica Makino
- Isoetes baculata Hickey & HP Fuchs
- Isoes biafrana alston
- Isoetes bischlerae HP Fuchs
- Isoetes bolanderi Engelm.
- Isoetes boliviensis U. Weber
- Isoestes boomii luebke
- Isoetes boyacensis HP Fuchs
- Isoetes bradei Herter
- Isoetes butleri Engelm.
- Isoetes caroliniana ( AA Eaton ) Luebke
- Isoetes chapmanii ( Engelm. ) Small
- Isoetes cleefii HP Fuchs
- Isoetes colombiana ( TC Palmer ) HP Fuchs
- Isoetes cubana Engelm. ex Baker
- Isoetes dispora hickey
- Isoetes echinospora Durieu - Hemispherus
- Isoetes ecuadoriensis Aspl.
- Isoetes engelmannii A. Braun
- Isoestes eshbaughii hickey
- Isoetes flaccida A. Braun
- Isoetes foveolata AA Eaton ex R. Dodge
- Isoetes gardneriana Kunze ex Mett.
- Isoestes georgiana luebke
- Isoetes gigantea U. Weber
- Isoetes herzogii U. Weber
- Isoetes hewitsonii hickey
- Isoetes hieroglyphica AA Eaton
- Isoetes howellii Engelm.
- Isoetes hyemalis DF Brunt.
- Isoetes hypsophila Hand.-Mazz.
- Isoetes karstenii A. Braun
- Isoetes killipii Morton CV
- Isoetes lacustris L. - Hemisphere Lake
- Isoetes lechleri Mett.
- Isoetes lithophila N. Pfeiff.
- Isoestes louisianensis thieret
- Isoetes maritima Underw.
- Isoetes martii A. Braun
- Isoetes melanopoda Gay & Durieu
- Isoetes melanospora Engelm.
- Isoetes mexicana Underw.
- Isoetes montezumae AA Eaton
- Isoetes novo-granadensis HP Fuchs
- Isoetes nuttallii A. Braun ex Engelm.
- Isoetes occidentalis LF Hend.
- Isoetes orcuttii AA Eaton
- Isoetes orientalis Hong Liu & Wang QF
- Isoetes ovata N. Pfeiff.
- Isoetes pallida hickey
- Isoetes palmeri HP Fuchs
- Isoetes panamensis Maxon & CV Morton
- Isoetes parvula hickey
- Isoetes perrieriana iversen
- Isoetes precocia RL Small & Hickey
- Isoetes pringlei Underw.
- Isoetes prototypus DM Britton
- Isoetes ramboi Herter
- Isoetes riparia Engelm. ex A. Braun
- Isoestes saracochensis hickey
- Isoetes savatieri Franch.
- Isoetes schweinfurthii Baker
- Isoetes setacea Lam.
- Isoetes sinensis Palmer
- Isoetes smithii HP Fuchs
- Isoetes stellenbossiensis AV Duthie
- Isoetes storkii TC Palmer
- Isoetes Taiwan De Vol
- Isoetes tegetiformans Rury
- Isoetes transvaalensis jermy & schelpe
- Isoetes triangula U. Weber
- Isoetes truncata ( AA Eaton ) Clute
- Isoetes tuckermanii A. Braun ex Engelm.
- Isoetes vermiculata hickey
- Isoetes virginica N. Pfeiff.
- Isoetes welwitschii A. Braun ex Kuhn
- Isoetes wormaldii R. Sim
- Isoetes yunguiensis Wang QF & WC Taylor
