Manihot Manihotoides (Euphorbiaceae) - CNCFlora

46 Flora Neotropica
its leaves during the dry periods, and some of the younger stems may die back during the
same periods. Its altitudinal distribution, one of the highest of any species of the genus,
makes it a potential donor of useful genetic materials for breeders interested in increasing
the tolerance of Manihot esculenta to drought and cool temperatures.
Key to the Subspecies of Manihot rubricaulis
1. Fruits smaller, less than 1.5 cm in length; seeds shorter, less than 1.0 cm in length.
5a. M. rubricaulis subsp rubricaulis.
1. Fruits larger, more than 1.5 cm in length; seeds longer, more than 1.0 cm in length.
5b. M. rubricaulis subsp isoloba.
5a. Manihot rubricaulis I.M. Johnston subsp rubricaulis
Manihot rubricaulis I. M. Johnston, Contr. Gray Herb. 68: 90. 1923; Croizat, Jour. Arnold Arb.
23: 222. 1942.
This subsp differs from subsp isoloba with respect to the size of fruits and seeds. The
fruits are relatively smaller, less than 1.5 cm in length from base to apex. The seeds are
also shorter, less than 1.0 cm in length. The leaf lobes are generally narrower, mostly less
than 1.0 cm in width. Fig 12D; 13A, B.
TYPE. Palmer 224: Mexico, Durango: City of Durango and vicinity (holotype, GH;
isotypes, (BM, F, GH, NY, UC, US-2).
DISTRIBUTION. (Fig 12C). Mexico, States of Sinaloa and Durango. MEXICO. Sinaloa:
Brandegee s n (UC) vicinity of Culiacan, Cerro Colorado, 1 Nov 1904.
5b. Manihot rubricaulis I. M. Johnston subsp isoloba (Standley) Rogers & Appan, stat
nov
Manihot isoloba Standley, Publ. Field Mus. Bot. 17: 197. 1937; Croizat, Jour. Arnold Arb. 23:
223. 1942.
This subspecies differs from the subsp rubricaulis with respect to the size of fruits
and seeds. The fruits are relatively larger, more than 1.5 cm in length (from base to apex).
The seeds are also bigger, over 1.0 cm in length. The leaf lobes are generally wider, mostly
not less than 1.0 cm in width. Fig 13C, D.
TYPE. Gentry 2372: Mexico, Chihuahua: Guasaremos, Rio Mayo 10 Aug 1936
(holotype, F; isotypes, ARIZ, MO, UC, US).
DISTRIBUTION. (Fig 12C). Mexico, States of Sonora, Chihuahua and Sinaloa. Alt
1000 to 2750 m. MEXICO. Sonora: Gentry 1468 (ARIZ, F, MO, UC, US) Bakachaka, Rio Mayo, 6
Jul 1935; Muller 3696 (NA, UC) Nacore Chico, Slopes above El Rio Bonito, 7 Oct 1939; Shreve
6753A (ARIZ, MICH) Santa Margarita Mountains, 6 miles E of Mina Verde, 23 Sep 1934; White 2758
(MICH) Cation de Los Apaches, N of Aribabi, 6 Sep 1939; White 2930 (GH, MICH, NA) La Palmita
between Granados and Bacadehuachi, 7 Jul 1940; White 3103 (ARIZ, GH, MICH) Cation de Bavispe,
Jul-Aug 1940; White 3647 (DS, GH, MICH) Piedra Parada, Sep 1940. Chihauhua: Gentry, Correl &
Arguelles 18083 (US) Rio San Juan Valley, 29 Oct 1959; Jones s n (POM-2) Guayanopa Canyon,
Sierra Madre Mountains, 24 Sep 1903; Knobloch 1335 (MICH) vicinity of Areponapuchie, Slopes of
Barranca de Urique, 23 Aug 1954; Lesueur 1249 (F, GH, MO, TEX, UC, US) Rio Aros, 6 Aug 1937;
Townsend & Barber 404 (BM, F-2, NY) Sierra Madres, near Seven Star Mine, 5 Sep 1899. Sinaloa:
Gentry 6583 (ARIZ, GH, MICH, MO, NY) Quebrado de Mansana, Sierra Surotato, Sep 1941.
VERNACULAR NAME. pato de gallo (Gentry 2372).
6. Manihot oaxacana Rogers & Appan, sp nov.
Frutices 2.0-5.0 m altae, glabrae; folia septemloba, lobus medianus ca 10.0 cm
longus, ca 4.0 cm latis; inflorescentia racemosa, brevis, ca 5.0 cm longa; flores staminati
conici; capsulae ca 1.5 cm longae; semina ca 0.9 cm longa.
Arborescent shrubs, 2.0-5.0 m tall, trunk diam ca 10.0 cm, branching begins above