Chamaecrista flexuosa var. flexuosa

Root variable in thickness, sometimes slender and monocarpic, sometimes (especially in savanna) developing a dilated crown or xylopodium, but not tuberously thickened or giving rise to subterranean caudex; stems prostrate or erect (1—) 1.5—12(—30), commonly 2-7 dm; pubescence highly variable, of lvs commonly scanty, sometimes 0, less often densely gray-pilosulous; lvs 4-ll(-14) cm, the expanded blades mostly narrowly lance- to linear-oblong; petiolar glands 1—4(—5), 0.2-0.9(-l) mm diam; lfts of adult lvs 20-65, of some upper lvs at least 25 pairs, (1—) 1.5—11(—13) x (0.4-)0.5-2.1(-3) mm; pedicels 11—28(—31) mm; sepals mostly 7-13 mm; petals either pale or bright yellow, up to (10.5—) 11.5—18(—19) mm.—Collections: 323.

Open sandy or grassy places, native in seasonally arid grassland (savanna, llano, campo), maritime sands, open pine-forest, and on rock-outcrops, becoming weedy and locally abundant in disturbed woodland, pasture, waysides, lakeshores and seasonally inundated river-banks or flood-plains, mostly below 450 m but ascending to 700 m in Guayana Highland and to 1300 m on the Brazilian Planalto in Goiás and Minas Gerais, discontinuously widespread from s. Mexico (s.-w. Mexico and the Pacific slope of Guerrero to Veracruz and Tabasco) and w. Cuba (Pinar del Río and Isla de Pinos) to n. Colombia (Magdalena), Venezuela (Maracaibo Basin and middle and lower Orinoco valleys, there extending to the Colombian shore in Vichada) and periphery of Guayana Highland in Venezuela (Bolívar, Amazonas), n. Brazil (Terr. do Roraima) and interior Guyana; lower Amazon valley in Brazil, downstream from mouth of Rio Tapajós (Pará); interruptedly on sandy shores and restinga of the Atlantic coast from Surinam to s.- e. Brazil (Rio Grande do Sul); and widely dispersed in caatinga, cerrado, campo, and capoeira over much of the Brazilian Planalto, from Maranhão, Rio Grande do Norte and Paraíba to São Paulo and n.-e. and s. Mato Grosso, thence feebly into the upper Madeira basin in Terr. Rondônia, Brazil, e. Bolivia (Sta. Cruz), Paraguay, and Argentina (Corrientes).—Fl. almost throughout the year, but most prolifically toward the end of the wet season and into the months following its end.—Tepeguajito (Oaxaca); canela de Macarico (Roraima); espadim de Mata (R. Grande do Norte); estrella matutina (Bolivia).

The synonymy listed under var. flexuosa, much of it already established in the literature, is of two sorts, based on: exactly typical plants (Colombian C. arenaria; Mexican C. amplistipulata) encountered in places remote from the original Brazilian one, this not exactly known but surmised to be one of the early Atlantic coastal settlements; or minor variants, almost certainly of independent origin, that differ in more or less densely pilosulous stems and foliage, the Brazilian vars. pubescens and cuyabensis, the Mexican C. picachensis. Other notable but unnamed variants not involving pubescence characters are a few examples (e.g. Lundell 6990 from Belize, GH) with conspicuously stipitate petiolar glands, and a notable population from La Jagua, Magdalena, Colombia (Haught 3575, NY, US) remarkable for its immense foliaceous stipules and correspondingly ample leaflets. The majority of populations from the Brazilian Planalto are characterized by very numerous and very small, firm leaflets coupled with relatively large flowers that open pale yellow (as in Ch. parvistipula) and fade pinkish-brown; but golden yellow petals that fade orange-brown have been noted from this region and appear to be commoner in the maritime habitats (as in restinga near Rio de Janeiro!) and in Central America. An unusual erect, fruticose form with stems up to 3 m tall (Irwin et al. 31262) encountered once in Sa. Agua de Rega in interior highland Bahia is not otherwise different from sympatric herbaceous or lowly suffruticose ones. A variant completely glabrous, even to the ovary, is known from Venezuela only (Pittier 14283, US).