Isoetes

Isoetes
Temporal range: Jurassic–Recent
Isoetes tegetiformans with U.S. penny for scale
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Lycophytes
Class: Lycopodiopsida
Order: Isoetales
Family: Isoetaceae
Genus: Isoetes
L.
Species

See text

Isoetes, commonly known as the quillworts, is a genus of lycopod. It is the only living genus in the family Isoetaceae and order Isoetales. There are currently [when?] 192 recognized species,[1] with a cosmopolitan distribution mostly in aquatic habitats but with the individual species often scarce to rare. Species virtually identical to modern quillworts have existed since the Jurassic epoch,[2] though the timing of the origin of modern Isoetes is subject to considerable uncertainty.[3]

The name of the genus may also be spelled Isoëtes. The diaeresis (two dots over the e) indicates that the o and the e are to be pronounced in two distinct syllables. Including this in print is optional; either spelling (Isoetes or Isoëtes) is correct.[4]

  1. ^ Troia, Angelo; Pereira, Jovani B.; Kim, Changkyun; Taylor, W. Carl (2016). "The genus Isoetes (Isoetaceae): a provisional checklist of the accepted and unresolved taxa". Phytotaxa. 277 (2): 101. doi:10.11646/phytotaxa.277.2.1. ISSN 1179-3163.
  2. ^ Wood, Daniel; Besnard, Guillaume; Beerling, David J.; Osborne, Colin P.; Christin, Pascal-Antoine (18 June 2020). "Phylogenomics indicates the "living fossil" Isoetes diversified in the Cenozoic". PLOS ONE. 15 (6): e0227525. Bibcode:2020PLoSO..1527525W. doi:10.1371/journal.pone.0227525. ISSN 1932-6203. PMC 7302493. PMID 32555586.
  3. ^ Wikström, Niklas; Larsén, Eva; Khodabandeh, Anbar; Rydin, Catarina (January 2023). "No phylogenomic support for a Cenozoic origin of the "living fossil" Isoetes". American Journal of Botany. 110 (1): e16108. doi:10.1002/ajb2.16108. ISSN 0002-9122. PMC 10108322. PMID 36401556.
  4. ^ International Code of Nomenclature for algae, fungi, and plants (Melbourne Code) see section 60.6: "The diaeresis, indicating that a vowel is to be pronounced separately from the preceding vowel (as in Cephaëlis, Isoëtes), is a phonetic device that is not considered to alter the spelling; as such, its use is optional."