Senna pendula var. pendula

  • Title

    Senna pendula var. pendula

  • Authors

    Howard S. Irwin, Rupert C. Barneby

  • Scientific Name

    Senna pendula (Willd.) H.S.Irwin & Barneby var. pendula

  • Description

    126i. Senna pendula (Willdenow) Irwin & Barneby var. pendula. Cassia pendula Humboldt & Bonpland ex Willdenow, 1809, l.c., sens. str.—"Habitat in America meridionals or, more exactly, fide Kunth in H.B.K., Nov. Gen. & Sp. 6(qu): 343. 1824,". . . in Nova Granata, prope Guaduas [Cundinamarca, Colombia], alt. 590 hex . . ."—Holotypus, collected by Humboldt & Bonpland in VII. 1801, B-WILLD 7948! isotypi, P- HBK!, Bonpland 1754, P!—Chamaefistula pendula (Willdenow) G. Don, Gen. Hist. Diehl. PI. 2: 452. 1832.

    Adipera bicapsularis sensu Britton & Killip, 1936, p. 177, ex parte, quoad syn.Arborescent at maturity but precociously flowering, at anthesis 1-7(-10) m, the foliage glabrous or the lfts sometimes weakly barbate dorsally in anterior angle of midrib; petiolar gland between proximal pair of lfts only; lfts 4-5(-6) pairs, the distal pair narrowly or broadly obovate 21—46 x 9-19 mm, the secondary camptodrome veins 6-8 pairs, tertiary venulation faint and irregular or 0; longest sepal 11-14.5 mm; longest petal 16-19 mm; long filaments 15-20 mm, their anther 89.2 x 1.4-1.8 mm, its beak 0.8-1.1 x 0.8-1 mm; blade of staminodes inversely deltate ±2 x 2.2-3 mm; ovary glabrous; style 6.5-10 mm; ovules 80-104; pod not seen mature, but seeds evidently 2-seriate.—Collections: 6.

    Riverbanks, thickets along streams, sometimes weedy on roadsides, 525-1250 m, apparently local in the Cordilleras of n. and centr. Colombia, from Santa Marta s. to Antioquia and Cundinamarca.—Fl. VI-XII.

    In its large flower, greatly elongated latero-abaxial filaments and long style var. pendula closely resembles the much commoner but distantly allopatric var. glabrata, from which it is weakly but consistently differentiated by the absence of sharp reticular venulation of the leaflets and by the broadly deltate blade of the staminodes. The var. hemirostrata is at least as close in proportions of flower parts and leaf-venulation, but is separable technically by the beaklike attenuation of the long anthers and physically by its habitat remotely distant in the Maya Mountains region of Belize and Guatemala. The discontinuities in range between these three intimately related forms are far from unprecedented. Examples from Cassieae are Chamaecrista desvauxii var. langsdorfii (Vogel) Irwin & Barneby, almost ubiquitous over the Brazilian Planalto, which reappears locally in the eastern Cordillera of Colombia; or Chamaecrista desvauxii (Colladon) Killip and Ch. zygophylloides (Taubert) Irwin & Barneby which survive in the Maya Mountain region as remnants of formerly widespread savanna floras.