Senna kurtzii

  • Title

    Senna kurtzii

  • Author(s)

    Howard S. Irwin, Rupert C. Barneby

  • Scientific Name

    Senna kurtzii (Harms) H.S.Irwin & Barneby

  • Description

    181.  Senna kurtzii (Harms) Irwin & Barneby, comb. nov. Cassia kurtzii Harms, Feddes Repert. Sp. Nov. 18: 94. 1922.-"Argentina: Mendoza, oberer Rio Salado, La Cienegita ... (F. Kurtz no. 7093 u. 7666-I. u. II. 1892-1893)."-Lectoholotypus, Kurtz 7093, †B = F Neg. 1696; no isotypus seen; paratypus, Kurtz 7666, NY!

    Cassia egregia Sandwith, Kew Bull. 1927: 181. 1927.-"[Argentina. Gob. Neuquen:] Near Chos Malal ... at 1200 m., November 20th, 1925, [H. F.] Comber 163 . . ."-Holotypus, K! = NY Neg. 1572.-Equated by Sandwith himself (K, annotation, 1929) with C. kurtzii, the synonymy accepted by Burkart, 1952, p. 166, in clave.

    Cassia conjugata sensu Kurtz, Verhandl. Bot. Ver. Brandenburg 35: 102. 1894; non Ruiz & Pavon.

    Cassia kurtzii sensu Bravo, 1981, p. 259, fig. 1, 5 (A-D).Stiffly many-stemmed xeromorphic microphyllous suffrutex ±2.5-4 dm, with woody caudex and ascending or diffusely incurved-ascending terete striate pale green hornotinous and basally persistent brown leafless annotinous branches, finely inconspicuously strigulose with appressed straight hairs up to 0.2-0.3 mm, but one or both faces of lfts glabrous and the calyx sometimes thinly hirsute, the lvs mostly 4-foliolate shorter than the internodes, the concolorous thick-textured lfts commonly livid-speckled, the pseudo-racemose inflorescence consisting of l(-2)-fld, shortly pedunculate racemes arising from axils of small distal lvs.

    Stipules livid-reddish glanduliform, tumidly convex dorsally, in outline ovate- apiculate 1-1.6 mm, persistent.

    Lvs 7-23 mm; petiole including slender yellowish pulvinus 1-7 mm, at middle 0.25-0.5(-0.6) mm diam, obscurely sulcate; gland between proximal pair, slenderly fusi- or subuliform 0.4-0.7 x 0.1-0.4 mm, yellowish or orange; pulvinules 0.5-0.8 mm; lfts of almost all lvs 2 pairs, occasionally only 1 pair or subpalmately 3-foil, the distal pair longer, these narrowly or broadly obovate obtuse apiculate or shallowly emarginate 4-13 x 2.2-6 mm, ±1.5-2.2 times as long as wide, at base inequilaterally rounded, the margin plane pallid or discolored, the midrib bluntly prominulous beneath, the venation otherwise fully immersed.

    Peduncles ascending (1.5-)5-26 mm; racemes all 1- or partly 2-fld, the axis then 1-7 mm; bract subtending the first (or only) fl resembling a stipule in shape and texture 1.5-2.2 mm, of the second fl obsolete; pedicels 12-20 mm; fl-buds globose, either glabrous above the puberulent base or erratically setose-hirsute with weak straight hairs up to ±1 mm; sepals submembranous, obovate or suborbicular, the small outer ones often dark at middle, the inner membranous-margined, well graduated, the smallest outer one 3-5 mm, the largest inner one 6-9.5(-10) mm; petals glabrous golden- then orange-yellow, 4 oblong-obovate obtuse, one abaxial one with thickened claw and oblong-elliptic blade turned almost at right-angles to it, this petal a little longer than the rest ±15.5-17 mm; androecium glabrous, the staminodes ±2 mm wide, the filaments of 4 median anthers 1.8-2 mm, of 3 abaxial ones very unequal 3-.9(-10) mm, that of the centric stamen shortest, the anthers of 4 median stamens 3.6-4 mm up to the very short (±0.3 mm) ascending beak, those of the 3 abaxial stamens subequal lunately lanceolate in outline 4-5.5 x 1.3-1.7 mm, tapering at summit but not beaked, dehiscent by oblique short slits; ovary strigulose and sometimes also loosely ascending-pilose; style glabrous 1-1.4 x 0.25-0.3 mm almost straight; ovules 20-22.

    Pod (not well known) ascending and curved outward, the stipe 6-9 mm, the body 6.5-9 x 0.8-1 cm compressed linear bicarinate by the sutures, the firmly papery valves elevated over seeds in the form of simple transverse ridges, the interseminal septa very narrow, the locules ±3 mm long; seeds transverse, narrowly ovate in outline 4.7-5 x 2.7-2.8 mm, compressed parallel with the valves, the moderately lustrous brown dark-spotted testa rugulose, the elliptic or almost round areole 0.4-0.8 x 0.2-0.35 mm; 2n = 24.-Collections: 9.

    Dry rocky hillsides and along intermittent stream beds, ±650-1600(-1700) m, locally plentiful in the e. foothills of the Andes drained by rios Atuel, Colorado and Neuquen, lat. 35°15'-39°S in Mendoza and Neuquen, Argentina.-Fl. XI-III.-Cacho carnero; yerba loca.