Araceae

Gonatopus Engl.

First published in A.L.P.P.de Candolle & A.C.P.de Candolle, Monogr. Phan. 2: 208 (1879)
This genus is accepted
The native range of this genus is Kenya to S. Africa.

Descriptions

Araceae, S.J. Mayo. Flora of Tropical East Africa. 1985

Morphology Reproductive morphology Inflorescences
Spadix subequal to spathe, lower part bearing pistillate flowers, upper part cylindric to clavate, bearing staminate flowers, separated from pistillate part by short constricted zone bearing sterile flowers Inflorescences 1–several, appearing before leaf but often persisting during its early development, subtended by several cataphylls, borne on erect very short to long penduncles Spathe convolute in lower part, forming a subglobose, cylindric or suburceolate tube, upper part an oblong to elliptic expanded limb reflexed at maturity
Morphology Reproductive morphology Flowers
Flowers unisexual, with perigon of 4(–6) decussate, fleshy, truncate to cucullate tepals Staminate flowers with stamens connate into a tube surrounding a central, cylindric to clavate pistillode; anthers dehiscing by apical pores, often exserted above tepals at dehiscence Pistillate flowers usually lacking staminodes, occasionally a solitary subcylindric staminode present between tepals and ovary; pistil ± laterally compressed; ovary 2-locular; ovules solitary in each locule, attached to base of septum; style short, thick; stigma discoid-capitate
sex Male
Staminate flowers with stamens connate into a tube surrounding a central, cylindric to clavate pistillode; anthers dehiscing by apical pores, often exserted above tepals at dehiscence
sex Female
Pistillate flowers usually lacking staminodes, occasionally a solitary subcylindric staminode present between tepals and ovary; pistil ± laterally compressed; ovary 2-locular; ovules solitary in each locule, attached to base of septum; style short, thick; stigma discoid-capitate
Morphology Reproductive morphology Fruits
Berry ovoid-ellipsoid, fleshy, 1–2-seeded
Morphology Reproductive morphology Seeds
Seed ovoid-ellipsoid, without endosperm; embryo macropodal, meristem lateral, superficial; testa smooth.
Morphology General Habit
Small to large, seasonally dormant, tuberous herbs
Morphology Stem
Stem an underground rhizome or subglobose tuber
Morphology Leaves
Leaf solitary, subtended by several basal cataphylls, glabrous, rarely pilose or scabrous; petiole pulvinate at base or centrally; blade broadly triangular to oblanceolate in outline, pinnately to quadri-pinnately lobed, ultimate lobes broadly elliptic to linear, often decurrent
[FTEA]

CATE Araceae, 17 Dec 2011. araceae.e-monocot.org

Distribution
E. Trop. Africa to S. Africa.
Diagnostic
Seasonally dormant geophytes; leaf solitary; petioles geniculate apically or centrally; leaf blade usually trisect with the three main divisions further subdivided; flowers unisexual, perigoniate; tepals usually 4, free, thick, truncate. Differs from Zamioculcas in having bipinnatifid to quadripinnatifid leaf blades (at least in lower pinnae), and connate stamen filaments.
General Description
HABIT : Seasonally dormant herbs, stem subterranean, a subglobose tuber or a cylindric, horizontal rhizome. LEAF : solitary, rarely pilose or scabrous, preceded by lanceolate cataphylls. PETIOLE : geniculate basally or centrally. BLADE : usually trisect, rarely not ( G. petiolulatus), primary divisions trifid to trisect or pinnatifid, or pinnatisect to quadri-pinnatifid, pinnae geniculate at junction with rachis, ultimate lobes varying from linear to broad-elliptic, often decurrent; primary lateral veins of each lobe pinnate, forming arching submarginal collective vein, higher order venation reticulate. INFLORESCENCE : 1-4 in each floral sympodium, appearing before or with leaves, subtended by several cataphylls. PEDUNCLE : erect, very short to long. SPATHE : constricted between tube and blade, tube convolute, subglobose, cylindric or suburceolate, blade oblong to elliptic, reflexed at anthesis, marcescent. SPADIX : subequal to spathe, female zone subcylindric, separated from male zone by very short, constricted zone of sterile flowers, male zone longer than female, cylindric to clavate, fertile to apex. FLOWERS : unisexual, perigoniate; tepals 4(-6), in 2 decussate whorls, fleshy, truncate to ± cucullate. MALE FLOWER : stamens with connate filaments forming tube around central, cylindric to clavate pistillode, often exserted above tepals at anthesis, connective slender, thecae dehiscing by apical pore. POLLEN : extruded in strands, extended monosulcate or fully zonate, hamburger-shaped, large (mean 76 µm., range 73-79 µm.), exine thick, foveolate, the foveolae scattered or grouped in fossulae, apertural exine psilate to ± verrucate. FEMALE FLOWER : usually lacking staminodes, exceptionally 1 staminode present, ovary 2-locular, ovules 1 per locule, anatropous, placenta basal-axile, style thick, somewhat attenuate, stigma large, discoid-hemispheric. BERRY : ovoid-ellipsoid, 1-2-seeded, red or orange to yellow, or whitish. SEED : ovoid-ellipsoid, testa thin, smooth, embryo large, plumule lateral, superficial, endosperm absent.
Habitat
Tropical evergreen forest; geophytes, on forest floor, also in rocky crevices with humus deposits.
[CATE]

Sources

  • 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, 17 Dec 2011.
    • http://creativecommons.org/licenses/by-nc-sa/3.0

  • Flora of Tropical East Africa

    • Flora of Tropical East Africa
    • http://creativecommons.org/licenses/by-nc-sa/3.0

  • Herbarium Catalogue Specimens

    • 'The Herbarium Catalogue, Royal Botanic Gardens, Kew. Published on the Internet http://www.kew.org/herbcat [accessed on Day Month Year]'. Please enter the date on which you consulted the system.

  • Kew Backbone Distributions

    • The International Plant Names Index and World Checklist of Vascular Plants 2026. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0

  • Kew Names and Taxonomic Backbone

    • The International Plant Names Index and World Checklist of Vascular Plants 2026. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 International Plant Names Index and World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0

  • Kew Science Photographs

    • Copyright applied to individual images