Senna macrophylla var. gigantifolia (Britton & Killip) H.S.Irwin & Barneby

  • Authors

    Howard S. Irwin, Rupert C. Barneby

  • Authority

    Irwin, Howard S. & Barneby, Rupert C. 1982. The American Cassiinae. A synoptical revision of Leguminosae tribe Cassieae subtrib Cassiinae in the New World. Mem. New York Bot. Gard. 35, part 1: 1-454.

  • Family

    Caesalpiniaceae

  • Scientific Name

    Senna macrophylla var. gigantifolia (Britton & Killip) H.S.Irwin & Barneby

  • Type

    Holotypus, Klug 1622, NY! = NY Neg. 4956; isotypi F, MICH, MO, US; paratypi, Klug 279, F, NY! —Cassia gigantifolia (Britton & Killip) Cowan ap. R. E. Schultes, Bot. Mus. Leaf!. Harvard Univ. 18: 146. 1958.

  • Synonyms

    Chamaefistula gigantifolia Britton & Killip, Cassia gigantifolia (Britton & Killip) R.S.Cowan, Chamaefistula barbinervis Pittier

  • Description

    Variety Description - Variably pubescent, the hornotinous branchlets, lf-stalks, lower face of lfts and axes of inflorescence varying from minutely subappressed strigulose to villosulous-pilose, the hairs up to 0.1-0.6(-1.2) mm, the vesture either pallid or rufescent; stipules highly variable, either setiform and 9-12 mm, less than 1 mm diam, or oblanceolate acute up to 20 x 2 mm, or greatly enlarged and foliaceous, resembling the leaflets and up to 12 x 5 cm; lvs 3-7.5 dm, the petiole including pulvinus (6-)7-28 cm, at middle 2-4.5 mm diam; rachis mostly 5.5-12(-15) cm, shorter than petiole; gland 2-5(-6) mm; distal lfts 18-44 x 7.5-18(-24) cm, the major camptodrome secondary veins 11-18; inflorescence either axillary to living lvs or cauliflorous, consisting either of a condensed leafless branchlet or reduced to 1(-2) shortly pedunculate racemes; sepals of var. macrophylla, but sometimes thinly pilosulous dorsally; petals (11-) 12-25(-34) mm.—Collections: 106. [Key: "Lvs extremely large, the larger cauline ones 3-7.5 dm, with petiole (6-)7-28 and rachis 5.5-12 cm, the blades of the distal pair of lfts 18-37 cm; Orinoco and Amazon basins, in Venezuela extending w. and n. to Cordilleras de Merida (Orinoco slope) and Costanera."]

    Distribution and Ecology - Primary and disturbed Hylaean forest of the upper Amazon and Orinoco basins, commonly on terra firme but occasional in varzea, on a variety of clay and sand soils (sometimes in caatinga), from ±130 up to 400-1300 m on the e. slope of the Andes in Venezuela, Ecuador and Peru, to 800 m on Guayana Highland (Sa. de Parima) and to 800-1400 m in cloud-forest of Cordillera Costanera in n. Venezuela, widespread as scattered individual trees or shrubs over n.-w. Brazil (Terr, do Roraima, Amazonas, Acre, Rondonia) and adjacent Peru (Cuzco, Huanuco, Loreto, San Martin, Amazonas), Ecuador (Napo-Pastaza), Colombia (Caqueta, Putumayo, Vaupes) and Venezuela (Amazonas), n. in Venezuela round the Andean sources of Rio Orinoco in Apure, Barinas and Merida and reappearing near crest of the coastal cordillera in e. Lara, Aragua and Distrito Federal.—Fl. nearly throughout the year.

  • Discussion

    Two collections from the Rio Negro-Orinoco divide in Vaupes, Colombia, are notable for elongate pedicels (up to 5.5-6.5 cm) and large flowers (longest petal 2.6-3.4 cm). One of them (Schultes et al 17964, US) was particularly cited by Cowan when he transferred Chamaefistula gigantifolia to Cassia. Following Cowan, we regard this, with Fernandez 2126 (US), as remarkable but taxonomically insignificant individual variants.

  • Common Names

    Matarro

  • Distribution

    Roraima Brazil South America| Amazonas Brazil South America| Acre Brazil South America| Rondônia Brazil South America| Huánuco Peru South America| Loreto Peru South America| San Martín Peru South America| Amazonas Peru South America| Napo Ecuador South America| Pastaza Ecuador South America| Caquetá Colombia South America| Putumayo Colombia South America| Vaupés Colombia South America| Amazonas Venezuela South America| Lara Venezuela South America| Aragua Venezuela South America| Distrito Federal Venezuela South America|