Monographs Details: Cassia obtusifolia L.
Authority: Irwin, Howard S. 1966. Contributions to the botany of Guiana. IV. Legumonosae Caesalpinioideae. Mem. New York Bot. Gard. 15: 112-128.
Description:Distribution and Ecology - BRITISH GUIANA. Atkinson Field, Irwin 34, 614.
As has been pointed out by DeWit^15 and Brenan,16 C. obtusifolia, long relegated to synonymy under C. tora L., is in fact distinct on the basis of several characters which show some correlation with geography. However, the neatness of the distinctions between these species as given by Brenan is somewhat reduced by the presence of at least one population, represented by the cited collections, having seed and pedicel characters of C. obtusifolia and the gland characters of C. tora, but differing from both species by a haploid chromosome number (n=12) probably representing an aneuploid loss of one from the n =14 common to both C. obtusifolia and C. tora, and a distinctive mode of growth.17 C. paraensis Ducke and a biglandular population in Colombia (Killip & Smith 14038) also represent deviations from typical C. obtusifolia. Nomenclatural adjustments, if any, should await the results of a planned investigation of variability in Brazilian populations.
Distribution:Guyana South America