| Arten: |
| Isoetes abyssinica Chiovenda |
| Isoetes acadiensis Kott |
| Isoetes aequinoctialis Welw. ex A. Braun |
| Isoetes alcalophila Halloy |
| Isoetes alpina Kirk |
| Isoetes andicola (Amstutz) L.D. Gómez |
| Isoetes andina Spruce ex Hook. |
| Isoetes asiatica (Makino) Makino |
| Isoetes attenuata C. R. Marsden & Chinnock |
| Isoetes australis S. Williams |
| Isoetes azorica Dur. |
| Isoetes baculata Hickey & H.P.Fuchs |
| Isoetes biafrana Alston |
| Isoetes bischlerae H.P.Fuchs |
| Isoetes bolanderi Engelm. |
| Isoetes bolanderi var. pygmaea (Engelm.) Clute |
| Isoetes boliviensis Weber |
| Isoetes boomii Luebke |
| Isoetes boryana Durieu |
| Isoetes boyacensis H.P.Fuchs |
| Isoetes bradei Herter |
| Isoetes brasiliensis H.P.Fuchs |
| Isoetes brevicula E.R.L.Johnson |
| Isoetes brochonii Moteley |
| Isoetes butleri Engelm. |
| Isoetes capensis Duthie |
| Isoetes capensis var. stephansenii (A.V.Duthie) Schelpe & N.C.Anthony |
| Isoetes caroli E.R.L. Johnson |
| Isoetes caroliniana (A.A. Eaton) Luebke |
| Isoetes castillonii H. P. Fuchs |
| Isoetes chaeturetii Mendes |
| Isoetes clavata Weber |
| Isoetes cleeffii H. P. Fuchs |
| Isoetes colombiana (T.C. Palmer) H. P. Fuchs |
| Isoetes coreana Y.H. Chung & H.K. Choi |
| Isoetes coromandelina L. f. |
| Isoetes coromandelina subsp. coromandelina L. f. |
| Isoetes coromandelina subsp. macrotuberculata C.R. Marsden |
| Isoetes cristata C. R. Marsden & Chinnock |
| Isoetes cubana Engelm. ex Baker |
| Isoetes dichotoma L.E.Mora & W.Hagemann |
| Isoetes dispora Hickey |
| Isoetes drummondii A. Br. |
| Isoetes drummondii subsp. drummondii A. Br. |
| Isoetes drummondii subsp. anomala C.R.Marsden & Chinnock |
| Isoetes durieui Bory |
| Isoetes echinospora Durieu |
| Isoetes Ekuadoriensis Aspl. |
| Isoetes ekmanii Weber |
| Isoetes elatior F. Muell. & A. Br. |
| Isoetes engelmannii A. Br. |
| Isoetes engelmannii var. georgiana Engelm. |
| Isoetes escondidensis Halloy |
| Isoetes eshbaughii Hickey |
| Isoetes flaccida Shuttlew. |
| Isoetes fuscomarginata H.P.Fuchs |
| Isoetes gardneriana Kunze ex Mett. |
| Isoetes georgiana Luebke |
| Isoetes gigantea U. Weber |
| Isoetes goebelii Weber |
| Isoetes gunnii A. Braun |
| Isoetes habbemensis Alston |
| Isoetes hawaiiensis W.C.Taylor & W.H.Wagner |
| Isoetes heldreichii Wettst. |
| Isoetes herzogii Weber |
| Isoetes hewitsonii Hickey |
| Isoetes hieronymi Weber |
| Isoetes histrix Bory & Dur. |
| Isoetes hopei J. R. Croft |
| Isoetes howellii Engelm. |
| Isoetes humilior F. Muell. ex A. Br. |
| Isoetes hyemalis D.F.Brunt. |
| Isoetes hypsophila Hand.-Mazz. |
| Isoetes inflata E.R.L. Johnson |
| Isoetes jaegeri Pitot |
| Isoetes jamaicensis Hickey |
| Isoetes japonica A. Br. |
| Isoetes killipii C.V. Morton |
| Isoetes kirkii A. Br. |
| Isoetes lacustris L. |
| Isoetes lechleri Mett. |
| Isoetes lithophila Pfeiffer |
| Isoetes louisianensis Thieret |
| Isoetes luetzelburgii Weber ex Luetzelburg |
| Isoetes malinverniana Cesati & De Not. |
| Isoetes maritima Underw. |
| Isoetes martii A. Br. |
| Isoetes melanopoda Gay & Dur. |
| Isoetes melanopoda f. pallida (Engelm.) Fernald |
| Isoetes melanospora Engelm. |
| Isoetes melanotheca Alston |
| Isoetes mexicana Underw. |
| Isoetes microvela D.F. Brunt & D.M. Britton |
| Isoetes mongerensis E.R.L. Johnson |
| Isoetes montana Weber |
| Isoetes muelleri A. Br. |
| Isoetes neoguineensis Baker ex F. v. M. |
| Isoetes neoguineensis var. rheophila J. R. Croft |
| Isoetes novo-granadensis H.P. Fuchs |
| Isoetes nuttallii A. Braun ex Engelm. |
| Isoetes occidentalis Hend. |
| Isoetes olympica A. Braun |
| Isoetes orcuttii Eaton |
| Isoetes organensis Weber |
| Isoetes ovata N. Pfeiff. |
| Isoetes pallida Hickey |
| Isoetes palmeri H.P.Fuchs |
| Isoetes panamensis Maxon & C.V. Morton |
| Isoetes parvula Hickey |
| Isoetes pedersenii H.P. Fuchs ex Hickey |
| Isoetes perrieriana Iversen |
| Isoetes philippinensis Merrill & Perry |
| Isoetes piedmontana (N. Pfeiffer) C. Reed |
| Isoetes pitotii Alston |
| Isoetes pringlei Underw. |
| Isoetes prototypus D.M. Britton |
| Isoetes pseudojaponica M. Takamiya & al. |
| Isoetes pusilla C.R.Marsden & R.J.Chinnock |
| Isoetes quilindanensis H. P. Fuchs |
| Isoetes ramboi Herter |
| Isoetes rimbachii H.P.Fuchs |
| Isoetes riparia Engelm. ex A. Br. |
| Isoetes riparia var. amesii (Eaton) Proctor |
| Isoetes riparia var. canadensis Engelm. |
| Isoetes riparia var. palmeri (Eaton ) Proctor |
| Isoetes riparia var. reticulata (Eaton) Proctor |
| Isoetes riparia var. robbinsii (Eaton) Proctor |
| Isoetes saracochensis Hickey |
| Isoetes savatieri Franchet |
| Isoetes schinzii H.P. Fuchs |
| Isoetes schweinfurthii A. Braun |
| Isoetes sehnemii H.P.Fuchs |
| Isoetes semilocularis J. E. Smith |
| Isoetes setacea Lam. |
| Isoetes sinensis Palmer |
| Isoetes sinensis var. coreana (Y. H. Chung & H. K. Choi) M.
Takamiya & al. |
| Isoetes smithii H.P.Fuchs |
| Isoetes spannagelii H.P.Fuchs |
| Isoetes spinulospora Jermy & Schelpe |
| Isoetes stellenbossiensis A.V. Duthie |
| Isoetes stevensii J. R. Croft |
| Isoetes steyermarkii H. P. Fuchs |
| Isoetes storkii T.C. Palmer |
| Isoetes taiwanensis De Vol |
| Isoetes tegetiformans P. M. Rury |
| Isoetes tenuifolia Jermy |
| Isoetes transvaalensis Jermy & Schelpe |
| Isoetes triangula U. Weber |
| Isoetes tripus A. Br. |
| Isoetes tuckermanii A. Braun ex Engelm. |
| Isoetes tuerckheimii Brause |
| Isoetes ulei Weber |
| Isoetes velata A. Braun |
| Isoetes velata subsp. velata A. Braun |
| Isoetes velata f. baetica (Willk.) Prada |
| Isoetes velata f. lereschii (Rchb.f. ex Leresche & Levier) Prada |
| Isoetes velata subsp. adspersa (A. Braun) Batt. & Trabut |
| Isoetes velata subsp. asturicensis (Lainz) Rivas Martinez & Prada |
| Isoetes velata subsp. dubia (Genn.) Batt. & Trabut |
| Isoetes velata subsp. intermedia (Trabut) Maire & Weiller |
| Isoetes velata subsp. longissima (Bory) Greuter & Burdet |
| Isoetes velata subsp. perralderiana (Milde) Batt. & Trabut |
| Isoetes velata subsp. tegulensis Batt. & Trabut |
| Isoetes velata subsp. tenuissima (Boreau) O. Bolós & Vigo |
| Isoetes vermiculata Hickey |
| Isoetes virginica Pfeiffer |
| Isoetes weberi Herter ex Weber |
| Isoetes welwitschii A. Braun ex Kuhn |
| Isoetes wormaldii R. Sim |