Senna candolleana (Vogel) 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


  • Scientific Name

    Senna candolleana (Vogel) H.S.Irwin & Barneby

  • Type

    Holotypus, cult. VII.32, G!—Cassia bicapsularis var. chilensis Bentham, Trans. Linn. Soc. London 27: 526. 1871.—C. quebracho Steudel, Nomenclator Bot. ed. 2, 1: 304, 307, pro syn. 1840.

  • Synonyms

    Cassia candolleana Vogel, Cassia bicapsularis var. chilensis Benth., Cassia quebracho Steud., Cassia frondosa Hook. & Arn., Cassia obtusa Clos

  • Description

    Species Description - Bushy shrubs and small trees at anthesis 2-5 m, with smooth green, obtusely angulate, densely leafy hornotinous branchlets, appearing glabrous but the young stems (often), the pulvinules of lfts and the raceme-axis with pedicels finely strigulose-pilosulous with gray hairs up to 0.2-0.4 mm, the foliage subconcolorous, the racemes all axillary to developed lvs but sometimes crowded toward apex of branchlets to form a small immersed or barely exserted panicle. Stipules erect herbaceous linear-oblanceolate or linear-attenuate 6-14 x 0.6-1.4 mm, entire or rarely toothed on side further from petiole, deciduous before the lf. Lvs 7.5-14 cm; petiole including swollen but firm pulvinus 1.5-2.7 cm, at middle 0.7-1.3 mm diam, obtusely 3-ribbed dorso-laterally, narrowly sulcate ventrally; rachis 3.5-8.5 cm, the longer interfoliolar segments 9-17 mm; gland between proximal pair sessile or stoutly short-stipitate, in profile 1.4-2.3 mm tall, the ovoid or oblong-ovoid obtuse or subacute (much eaten) body 0.4-0.7 mm diam; pulvinules 1.6-2.7 mm; lfts 4-7 pairs, moderately accrescent distally (the penultimate pair sometimes longest), in outline oblong or oblong-obovate emarginate, less often broadly obovate emarginate, the longest pair (2.3-)2.8-4.5 x 0.9-1.7 cm, (2-)2.4-3.1 times as long as wide, at strongly asymmetric base rounded or subcordate on proximal and cuneately decurrent on distal side, the margin plane, the centric midrib immersed or almost so above, cariniform beneath, the 6-9 pairs of major camptodrome and intercalary secondary veins with tertiary connecting and reticular venules all ± raised on both sides, strongly so beneath. Racemes rather densely 15-30-fld, the commonly several simultaneously expanded fls raised nearly to level of the erect buds, the axis together with peduncle becoming ±6-9 cm; bracts subulate or linear-lanceolate 2-5 mm caducous; pedicels at and after anthesis 1.7-2.7 cm; fl-buds subsymmetrically obovoid, glabrous or puberulent at base; sepals subpetaloid yellowish, finely veined, obovate obtuse, strongly graduated, the outermost 4.5-6.5 mm, the longest inner one 7.5-11.5 mm; petals (of Coluteoideae) glabrous golden-yellow drying pale yellow or stramineous brown-veined, the longest 12-17 mm; androecium glabrous, the staminodes 1-1.3 mm wide, the filaments of 4 median stamens 1.4-2.4 mm, of 2 latero-abaxial ones dilated 7.5-10.5 mm, of the sterile centric abaxial one ±4 mm, the anthers of 4 median stamens 4-5 x 1.1-1.3 mm, almost straight, of 2 long abaxial ones lunately lanceolate in profile 5.5-6 x 1.3-1.5 mm, of the centric abaxial one 4-6.5 x 0.5-0.9 mm, the 6 fertile anthers obscurely strangulate just below apex, there truncate and 2-porose; ovary strigulose; style glabrous 2-2.5 mm, slightly incurved and tapering distally, 0.15-0.2 mm diam at the terminal minute stigmatic cavity. Pod erratically ascending or obliquely declined, the stout stipe 3-4 mm, the body linear in outline, commonly a little decurved 6-9.5 x 0.6-0.7 cm, when fully mature terete or strongly turgid, the sutures little prominent often irregularly undulate, the thick green convex, ultimately coriaceous brown or blackish valves corrugated by shallow depressions at each interseminal septum, externally vein- less, the septa usually broad and complete, the pulpless seed-locules 2.5-4 mm long; seeds transverse uniseriate, turned with broader face to the septa, plumply obovoid or oblong-obovoid 4.2-5.3 x (2.6-)2.8-3.6 mm, the smooth testa dark brown around the periphery, paler on the faces, the pale patch sometimes differentiated into a shadowy areole, when fully ripe either dull or lustrous, lacking a waxy exocarp.—Collections: 16.

    Distribution and Ecology - Thickets and open hillsides, 5-800 m, locally plentiful in the coastal Cordillera of Mediterranean Chile, in the provinces of Coquimbo, Valparaiso and Santiago.-Fl. almost throughout the year.

  • Discussion

    Bentham was perplexed by carpological variation within his polymorphic macrospecies Cassia bicapsularis and interpreted the quebracho of coastal Chile as a variety characterized by a narrow pod with uniseriate seeds combined with relatively small firm, prominently venulose leaflets. These features can in fact be almost exactly matched in some local, distantly allopatric forms of our S. pendula, in particular in the brachystylous S. pendula var. ambigua of coastal southeastern Brazil. However, the orifice of the long anthers in all forms of S. pendula takes the form of a U-shaped aperture divided by a septum that remains attached only to its adaxial rim; whereas in S. candolleana the orifice remains biporose, the septum being permanently attached to both rims. This small feature, in conjunction with a remotely allopatric range, serves to liberate S. candolleana from the orbit of S. pendula sens. lat. but does not, of course, obscure the manifest relationship between them. The segregation of S. candolleana usefully reduces the all too protean compass of variation encountered in S. pendula. On the coast of Coquimbo S. candolleana enters the range of S. cumingii sens, lat. which may be similar at anthesis but is very different in the compressed pod and in orientation of the areolate seeds. The flower of S. cumingii var. coquimbensis, which most closely resembles S. candolleana in broad outline and texture of leaflets, differs in the elongated style.

  • Common Names


  • Distribution

    Coquimbo Chile South America| Valparaíso Chile South America| Santiago Chile South America|