Gearum N.E.Br.
  • J. Bot. 20: 196 (1882) 

Notes: Distribution: C. Brazil

General Description

HABIT : seasonally dormant, tuberous herbs with aromatic exudate when cut. LEAF : solitary. PETIOLE : sheath distinct, about half length of petiole. BLADE : subpalmatifid, lobes 5, central 3 lobes broader, elliptic, cuspidate, basal 2 narrower, lanceolate; primary lateral veins of each lobe forming submarginal collective vein on each side, higher order venation reticulate. INFLORESCENCE : solitary. PEDUNCLE : very short, much shorter than petiole. SPATHE : erect, slightly constricted, purplish, tube subcylindric, convolute, blade erect, gaping, oblong, cuspidate. SPADIX : shorter than spathe, fertile to apex, female zone shorter than male and separated from it by a sterile zone of synandrodes. FLOWERS : unisexual, perigone absent. MALE FLOWER : 4-androus, consisting of very shallow, subrhombic, truncate, subpeltate synandrium, thecae ± remote, situated near margin of synandrium, globose to oblong-ellipsoid, dehiscing by apical pore or occasionally by an oblique slit. POLLEN : ellipsoid, inaperturate, large (mean 56µm, range 52-60 µm), exine smooth (psilate) to scabrous-granulate. STERILE MALE FLOWERS : composed of irregularly elongated, shallow, truncate synandrodes. FEMALE FLOWER : densely crowded, gynoecium surrounded by usually 4 staminodes, staminodes laterally compressed, thick, rounded to obovoid, ovary subglobose, 3-4-locular, ovules 1 per locule, orthotropous, rather elongate, placenta axile at base of septum, stigma ± discoid, slightly (3-)4-lobed. BERRY : unknown. SEED : unknown.

Diagnostic Description

Seasonally dormant tuberous geophytes; peduncle very short. much shorter than petiole; flowers unisexual, perigone absent; male flower a truncate synandrium; female flowers surrounded by a whorl of free staminodes; ovules orthotropous. Differs from Gorgonidium and Synandrospadix in having pedatisect or subpalmatifid leaf blade, styles and synandria short and squat or synandria very flat, staminodes in female flowers thick, obovoid or subtrapezoid.


Tropical open herbaceous vegetation (“campo cerrado”); geophytes in low-lying sites prone to periodic flooding.


C. Brazil.

Distribution Map

  • Native distribution
Found in
  • Southern America Brazil Brazil North
  • Brazil West-Central

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
  • B 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; Retrieved 2011 onwards
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