Neotropical Typhaceae

Lidyanne Yuriko Saleme Aona

Universidade Federal do Recôncavo da Bahia (UFRB), Brazil. 

Description

Perennial plants with starchy rhizome, emergent from shallow water or growing in wet soil, sometimes completely submersed and floating. Leaves alternate, distichous, base strongly sheathing and elongate, parallel-veined blade, basal in young, sterile plants and forming an erect (false) stem, flowering plants also dispersed along 'stem', rarely bearing only hypsophylls. Inflorescence racemose, with numerous monoecious, hypogynous flowers grouped into very dense cylindric spikes. Flowers male and female, male flowers at base of inflorescence, female flowers near apex; perianth of 1-several inconspicuous tepals or numerous slender bristles; stamens (1-)3(-8), the filaments distinct or connate; anthers basifixed, dithecal; gynoecium pseudo-monomerous, with a single fertile carpel, less often with ca. 2-3 fully developed carpels connate to form a compound ovary; stigmas or branches of common style accordingly 1-3; 1 pendulous ovule/carpel, bitegmic. Fruit small, dry, indehiscent or dorsally dehiscent; seeds with straight embryo.

Notes on delimitation

  • Typhaceae are placed within Poales and, together with the Bromeliaceae, present three-nucleotide deletion in the atpA gene (Stevens 2009).

Distribution in the Neotropics

  • Typha L. (ca. 13 spp. Central and South America).

Distinguishing characters (always present)

  • Flowers monoecious (male and female), hypogynous, grouped into very dense cylindric spikes.
  • Typhaceae are wind pollinated, and have very reduced flowers.

Other important characters

  • Rhizomatous aquatic.
  • Flowers very much reduced.

Key differences from similar families

  • In general morphology the Typhaceae can be confused with Cyperaceae, Juncaceae and Poaceae. However, Typhaceae can be distinguished by the presence of monoecious flowers grouped into very dense cylindric spikes that reach up to 30 cm long, with female flowers at the apex and male flowers towards the base of the spike.

Number of genera

One Neotropical genus: Typha.

Notable genera and distinguishing features

  • Typha is a robust, rhizomatous herb that likes damp conditions.
  • Erect, linear leaves.
  • Distinctive, elongated, dense cylindrical inflorescences.
  • The part containing the carpellate flowers is borne below and separate from the part with the staminate flowers.

(Stevens 2009)

Status

  • Typha is native to the Americas and widespread in the Neotropics.

General notes

  • From the economic point of view, the floral involucre of Typha provides excellent quality fibre to be used in the textile industry.
  • Its leaves can also be used as a source of good quality cellulose to produce paper or for crafts.
  • The starch-rich rhizome is edible and its pollen, which is abundant and nutritious, is used in the pharmaceutical industry.

Important literature

Stevens, P.F. (2001 onwards). Angiosperm Phylogeny Website. Version 9, February 2009 [and more or less continuously updated since]. http://www.mobot.org/MOBOT/research/APweb/.

Stevenson, D.W. 1998. Typhaceae, pp. 457-461. In: K. Kubitzki (ed.) The families and genera of vascular plants volume 4. Springer-Verlag. Berlin.

How to cite

Aona, L.Y.S. (2009). Neotropical Typhaceae. In: Milliken, W., Klitgård, B. & Baracat, A. (2009 onwards), Neotropikey - Interactive key and information resources for flowering plants of the Neotropics. http://www.kew.org/science/tropamerica/neotropikey/families/Typhaceae.htm.