Manihot Manihotoides (Euphorbiaceae) - CNCFlora

Systematic Position of the Genus 137
4.0-7.0 cm wide, lamina edges purplish, apex obtuse to broadly acute, base of lobes ca
1.0 cm wide; lowest lobes similar to median lobes in size and outline. Inflorescence
monoecious, terminal, a cluster of short racemes arising from one basal point ca 4.0 cm
long, occasionally as long as 8.0 cm; all parts glabrous, sometimes with a bluish bloom;
bracteoles foliaceous, 1.25 cm long, 0.8 cm wide; bractlets foliaceous, 0.75 cm long, 0.4
cm wide. Pistillate flowers restricted to the base of the upper 1/2 of the inflorescence,
pedicels 1.0 cm long, tepal 1.0 cm long, cleft to base into 5 lobes, ovary subglobose.
Staminate buds ovoid-ellipsoid; tepal 1.0 cm long, cleft 1/3 way down into 5 lobes;
stamens 10, in 2 whorls of 5 each. Capsules 1.25 cm long; surface smooth; apex rounded,
dehiscence septicidal. Seeds 0.8 cm long, oblong, with a well-developed caruncle.
Fig 59A, B.
TYPE. Pohl 6040 (and on some specimens also 1657). Brasil, Goias: ad Rio Macaco
et Areas (syntypes, F, G, K, W-2).
DISTRIBUTION. (Fig 58D). Brasil, states of Goias, Minas Gerais and Distrito Federal.
Alt ca 1000 m. BRASIL. Goias: Dawson 14149 (F) region of Chapada dos Veadeiros, 13 Apr 1956;
Irwin, Grear, Souza & dos Santos 12443 (F, MICH, NY, SP, UB, US) Chapada dos Veadeiros, 9 Feb
1966; Irwin, Grear, Souza & dos Santos 13694 (F, G, NY, RB, UB, UC) Cerrado, circa 20 km N df
Cristalina, 7 Mar 1966; Irwin, Grear, Souza & dos Santos 13696 (F, GH, K, MO, NY, SP, UB, US)
Cerrado, circa 20 km N of Cristalina, 7 Mar 1966; Irwin, Grear, Souza & dos Santos 15565 (F, NY,
UB) Corrego Itaquira, circa 30 km N of Formosa, 2 May 1966; Irwin, Souza & dos Santos 10014 (F,
MO, NY, RB, S, SP, UB) 75 km N of Cristalina on road to Brasilia, 6 Nov 1965; Irwin, Souza & dos
Santos 9502 (F, GH, MICH, MO, NY, RB, SP, UB, US, W) near waterfall, 24 km NW of Veadeiros,
road to Cavalcante, 22 Oct 1965;Macedo s n (PUL) Jacuba, Niquelandia, 24 Feb 1956;Pohl Icon Tab.
33 (W); Pobl Icon Tab. 34 (W); Pohl 1183 (F-2, G, W-2) ad Rio Macacco et Areas; Prance & Silva
58227 (NY-2) 5-10 km N of Veadeiros, Valley of Rio Parana, Cerrado, 19 Jul 1964. Distrito Federal:
Irwin, Souza & dos Santos 10723 (F, NY, UB) Campo near Aparecido, circa 50 km W of Brasilia, 29
Nov 1965. Minas Gerais: Macedo 4264 (PUL, RB) Araxa, 5 Feb 1956; Saint-Hilaire 488 (F, P).
49. Manihot irwinii Rogers & Appan, sp nov n
Frutices, ca 1.5 m altus, aliquot ascendens caules ab ligneum basim. Folia coriaceus,
glaucissima in abaxialis pagina; venae rubelli. Inflorescentia aliquot racemi exoriens uno
basalis punctum, bracteolae et ramuli semifoliaceus, ca 1.0 cm longi, ca 0.3 cm lati,
purpurascens; tepalum purpurascens. Capsulae 1.6 cm longae. Semina 1.0 cm longae,
oblongae.
Shrubs, ca 1.5 m tall, with several ascending stems from woody base. Young stems
obtuse-angled in cross section, glabrous, glaucous, purplish tinged; mature stems glabrous.
Leaves alternate; stipules caducous, 0.5 cm long, 0.1 cm wide, glaucous; petioles ca 9.0
cm long, terete, glabrous, reddish, petiole attachment to lamina basal, nonpeltate; lamina
coriaceous, adaxial surface dark green, abaxial surface with a thick bloom, abaxial surface
wax pattern smooth; venation camptodromous, veins glabrous, reddish, lamina 3 lobed,
leaves associated with the inflorescence frequently nonlobed; median lobes ca 6.0 cm
long, ca 1.0 cm wide, elliptic, apex acute, obtuse or caudate, base of lobes ca 1.0 cm
wide, lamina prominently overlapping at sinus; lowest lobes similar in size to median
lobes, nonsymmetric. Inflorencence monoecious, terminal, a cluster of several racemes
arising from one basal point, ca 7.0 cm long, all parts except interior surface of tepals
glabrous, with a thick bloom; bracteoles semifoliaceous, 1.0 cm long, 0.3 cm wide,
purplish tinged, glabrous, margin entire; bracteoles semifoliaceous, 0.7 cm long, 0.2 cm
wide, purplish tinged, margin entire. Pistillate flowers restricted to the base of the upper
half of the inflorescence; pedicels 1.25 cm long; tepal 0.9 cm long, cleft to base into 5
strap-shaped lobes, interior surface of lobes pubescent, yellowish green with considerable
amount of purlish pigmentation; ovary subglobose, slightly elongated, the trifid stigma
moderately lobed and lobulate. Staminate flowers medium sized, tepal 0.9 cm long,
' This species is named in honor of Dr. Howard S. Irwin of The New York Botanical Garden. Dr.
Irwin's studies of the flora of the central Brazilian plateau have contributed greatly to our knowledge
and understanding of this little known region.