Monographs Details: Senna dariensis var. smaragdina 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.
Description:Variety Description - Resembling var. gatunensis in pubescence, petiole-length, and relatively long corolla, but the calyx usually smaller and externally glabrous from base or middle upward; pod much broader than that of other vars. of C. dariensis, 8-12 mm diam, the seeds biseriate.—Collections: 10. [Key: "Pod 8-12 mm diam; anthers (usually) hispidulous overall with hairs ±0.2 mm; coastal lowland forest of Ecuador and s.-w. Colombia. Petiole 2-4(-5) cm; lfts densely strigulose beneath; sepals glabrous throughout or beyond middle, the longest 4-8 mm."]

Distribution and Ecology - Humid virgin forest, sometimes along streams, persisting in second-growth woodland, below 650 m, coastal plain and first foothills of the Pacific coast of s. Colombia (Narino) and adjacent Ecuador (Esmeraldas, Imbabura and Los Rios).—Fl. III-IV, VII-VIII, perhaps through the year.

Discussion:A clearly distinct senna, perhaps when better known specifically distinguishable from S. dariensis by the pod alone, in foliage hardly different from var. gatunensis, and resembling distantly allopatric var. hypoglauca (of which the pod is still wanting) in the small glabrate calyx. The densely pubescent anthers furnish a good differential character for flowering specimens. The variety was collected first in 1841 at Tumaco by Hinds and Barclay. Their specimens, consisting of foliage with one damaged pod of the preceding season, were among those cautiously identified by Bentham as "C. bacillari affin." Mistakenly referred (Little 6210) by Killip (in Little, Caribbean Forester 9(3): 243. 1948) to Cassia scandens R. & P. Our one specimen from Los Rios, Ecuador (Dodson 5472, US) differs from the rest in the relatively large calyx (inner sepal to ±8 mm) and glabrescent anthers. Fruit is required to settle the identity of this population. An indifferent specimen from Tumaco, Narino (Romero-Castaneda 2761, F) with a few broken immature flowers detached from the lvs may belong here, but has glabrous anthers.
Distribution:Nariño Colombia South America| Esmeraldas Ecuador South America| Imbabura Ecuador South America| Los Ríos Ecuador South America|