Manihot Manihotoides (Euphorbiaceae) - CNCFlora

Systematic Position of the Genus
Key to the Genera Manihot and Manihotoides
1. Inflorescence many flowered; leaves evenly spaced on stem, leaf lobes usually more than 3.0
cm long.
1. Manihot.
1. Inflorescence uniflorous, rarely 2 flowered; leaves borne at the apex of short lateral shoots,
leaf lobes usually less than 3.0 cm long.
2. Manihotoides.
Key to the Sections of Manihot
1. Taxon existing entirely under domestication, not known to be growing wild; cultivated for
its edible roots; nodes on stem distinctly enlarged.
Sect 1. Manihot (p. 25).
1. Taxa existing mostly as wild populations, a few under cultivation, but grown for latex only
and not for edible roots; nodes on stem slightly or not enlarged.
2. Taxa native in North and Central America (USA, Mexico, Guatemala, British Honduras,
Honduras, El Salvador, Nicaragua, Costa Rica and Panama).
3. Shrubs or vines; fruits small (less than 1.75 cm long from base to apex), seeds small (less
than 1.5 cm long).
Sect 2. Parvibracteatae (p. 34).
3. Trees; fruits large (more than 1.75 cm long from base to apex), seeds large (more than
1.5 cm long).
Sect 3. Foetidae (p. 65).
2. Taxa native in South America (Colombia, Venezuela, Trinidad/Tobago, Guyana,
Suriname, Guyane Francaise, Ecuador, Peru, Brasil, Paraguay, Uruguay, Argentina) and
West Indies.
4. Leaves deeply lobed; the sinus greater than half the length of the lobe.
5. Plants caulescent; usually more than 25.0 cm tall; leaves widely spaced on stem;
stipules mostly caducous, rarely persistent, usually less than 1.0 cm long; inflores-
cence with pistillate and staminate flowers, indeterminate, racemose or paniculate.
6. Leaf lobes variously shaped, but not linear or narrowly lanceolate.
7. Erect woody shrubs, usually more than 0.5 m tall, leaves larger, median lobes
usually more than 4.0 cm long.
8. Abaxial surface of leaves glabrous or sparsely to densely pubescent, but not
tomentose.
9. Inflorescence a panicle.
10. Erect shrubs or trees, (except M. filamentosa, a vine-like shrub in section
6-see second 12 of this key).
11. Low to medium tall shrubs or occasionally small trees, usually less
than 5.0m tall; leaves membranaceous; petiole attachment mostly
basal, rarely peltate, when peltate, lamina between petiole-midrib
junction and basal edge of leaf is less than 0.5 cm wide; seeds oblong;
bracts and bracteoles with entire margin.
12. Median lobes entire or shallowly pandurate, when pandurate, the
apical region not prominently dilated; population native in regions
other than the Caribbean coast and the adjoining regions of
Venezuela and Colombia. Sect 4. Heterophyllae (p. 77).
12. Median lobes usually deeply pandurate, rarely entire, apical region
prominently dilated and more or less triangular (Fig 47D); populations
native on the Caribbean coast and the adjoining interior
regions of Venezuela and Colombia. Sect 6. Carthaginenses (p. 113).
11. Trees or tall shrubs, usually more than 5.0 m tall; leaves coriaceous;
petiole attachment mostly peltate, rarely basal, when peltate, lamina
between petiole-midrib junction and basal edge of leaf more than 0.5
cm wide; seeds rounded; bracts and bracteoles if foliaceous (more than
0.5 cm wide) with entire margin, otherwise (less than 0.5 cm wide)
with dentate margin.
Sect 11. Glaziovianae (p. 175).
10. Vine-like shrubs, clambering over other vegetation. Sect 12. Peruvianae (p. 189).
9. Inflorescence a raceme, single or several arising from a common base.
13. Leaf lobe bases usually not extremely constricted, but if constricted the
lobes overlapping at sinus; lamina at lobe bases usually more than 0.3 cm
wide, lamina between base of sinus and petiole-midrib junction usually
more than 0.3 cm wide.
14. Low to medium shrubs; usually less than 3.0 m tall.
15. Erect shrubs.
16. Lamina coriaceous, adaxial surface dark green, abaxial surface
distinctly glaucous, usually violet tinged; midribs usually purplish.
Sect 7. Quinquelobae (p. 118).
23