Orontium L.
  • Sp. Pl.: 324 (1753) 

Notes: Distribution: E. U.S.A. to Texas

General Description

Laticifers present, simple, articulated. HABIT : seasonally dormant, aquatic herbs, continuation shoot of stem sympodium arising in axil of last foliage leaf of each article and beginning with a foliage leaf rather than a cataphyll, rhizome short, erect, buried deep in soil. LEAVES : several. PETIOLE : terete, sheath long. BLADE : oblong-elliptic, held above water surface or floating on it; primary lateral veins arising at base of blade, arcuately ascending and running into apex, secondary laterals inconspicuous and parallel to primaries, higher order venation transverse-reticulate. INFLORESCENCE : 1-2 in each floral sympodium. PEDUNCLE : absent, spadix supported on elongated stipe. SPATHE : a short, inconspicuous, simple bract, inserted at point of attachment of inflorescence to rhizome, enclosing young spadix, later separated from it and disintegrating. SPADIX : held above water level, conical, slender, flowering acropetally, golden yellow, peduncle-like stipe very long, often partly submerged, greenish to red-brown with white, swollen apical part. FLOWERS : bisexual except for some male flowers at spadix apex, perigoniate, tepals 6, sometimes 4, short, about as long as wide, fornicate, subtruncate, irregularly imbricate. STAMENS : 6, sometimes 4, filaments flattened, connective slender, thecae ellipsoid, dehiscing by broad apical slit. POLLEN : monosulcate, ellipsoid, large (mean 64 µm., range 55-73 µm.), exine densely foveolate-fossulate. GYNOECIUM : ovary depressed-globose, broader than long, 1-locular, ovule 1, hemianatropous, held horizontally, funicle short, placenta basal, style ± absent, stigma small, subsessile, discoid-hemispheric. BERRY : depressed-globose, green, 1-seeded, partially immersed in spadix axis. SEED : ± globose, testa thin, smooth, ± transparent, decaying at maturity, raphe conspicuous in furrow-like depression, hilum reddish, embryo large, almost globose to depressed-globose, with a small internal cavity situated below the hilum, outer cell layers green, plumule well-developed with 1(-2) filiform leaf primordia, endosperm absent.

Diagnostic Description

Seasonally dormant aquatic herbs with short erect rhizome; petiole cylindric, leaf blade oblong-elliptic; spathe not normally visible, inserted at attachment to rhizome, stipe very long, white apically, spadix cylindric, yellow; flowers bisexual, perigoniate, with 6 tepals. Differs from Symplocarpus in inconspicuous spathe, very long stipe, cylindric spadix and basal placentation. Differs from Calla in leaf shape, presence of perigone, and in lacking ligule on petiole sheath.


Temperate wetlands, occurring from sea level to 900m alt.; partly submersed aquatic plant growing in open or partially shaded swamps, marshes, lakes and ponds, in dense stands or scattered colonies.


E. U.S.A. to Texas.

Distribution Map

  • Native distribution
Found in
  • Northern America Northeastern U.S.A. Connecticut
  • Masachusettes
  • New Jersey
  • New York
  • Pennsylvania
  • Rhode I.
  • West Virginia
  • South-Central U.S.A. Texas
  • Southeastern U.S.A. Alabama
  • Delaware
  • District of Columbia
  • Florida
  • Georgia
  • Kentucky
  • Louisiana
  • Maryland
  • Mississippi
  • North Carolina
  • South Carolina
  • Tennessee
  • Virginia

Included Species


  • 1 Govaerts, R. & Frodin, D.G. (2002). World Checklist and Bibliography of Araceae (and Acoraceae): 1-560. The Board of Trustees of the Royal Botanic Gardens, Kew.
  • 2 Gardens, K.""Royal Bot World Checklist of Selected Plant Families. (2008).
  • 3 Mayo, S.J., Bogner, J. & Boyce, P.C. The Genera of Araceae. (Royal Botanic Gardens Kew: 1997).

 Information From

CATE Araceae
Haigh, A., Clark, B., Reynolds, L., Mayo, S.J., Croat, T.B., Lay, L., Boyce, P.C., Mora, M., Bogner, J., Sellaro, M., Wong, S.Y., Kostelac, C., Grayum, M.H., Keating, R.C., Ruckert, G., Naylor, M.F. and Hay, A., CATE Araceae, 14 Dec 2011 . 17 Dec 2011.
  • A All Rights Reserved
eMonocot. (2010, 1st November). Retrieved Wednesday, 8th February, 2012, from http://e-monocot.org.
  • B
  • C Content licensed under Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License
World Checklist of Selected Plant Families
WCSP 2014. 'World Checklist of Selected Plant Families. Facilitated by the Royal Botanic Gardens, Kew. Published on the Internet; http://apps.kew.org/wcsp/ Retrieved 2011 onwards
  • D See http://kew.org/about-kew/website-information/legal-notices/index.htm You may use data on these Terms and Conditions and on further condition that: The data is not used for commercial purposes; You may copy and retain data solely for scholarly, educational or research purposes; You may not publish our data, except for small extracts provided for illustrative purposes and duly acknowledged; You acknowledge the source of the data by the words "With the permission of the Trustees of the Royal Botanic Gardens, Kew" in a position which is reasonably prominent in view of your use of the data; Any other use of data or any other content from this website may only be made with our prior written agreement.