Cassia catharticoides

  • Title

    Cassia catharticoides

  • Author(s)

    Howard S. Irwin, Rupert C. Barneby

  • Scientific Name

    Cassia catharticoides H.S.Irwin & Barneby

  • Description

    6.  Cassia catharticoides Irwin & Barneby, sp. nov., habitu toto sed imprimis floribus solitariis e folii normalis axillo ortis corollaque magna valde asymmetrica C. catharticae, foliolisque 2-6-jugis ejus var. paucijugae propius affinis, sed foliolis elliptico-oblanceolatis eximie revolutis (nec obovatis fere planis) costa ventre alte depressa canaliculatis dorso crasse carinatis cito distinguenda. - BRAZIL. Minas Gerais: prope Serra de Ibitipoca, mun. Bias Fortes, distr. Ibitipoca, VI. 1896, fl. cum fr. jun., H. de Magalhaes in herb. Commissao Geografica e Geologica de Minas 1377. - Holotypus, R (no. 102228); clastotypus (fragm). NY.

    Shrubs of unknown stature, in habit resembling C. cathartica var. paucijuga, with soon naked, blackish trunks branched distally into a dense crown of foliage, except for the glabrate, glutinously glossy upper face of the lfts densely viscous-pilosulous throughout with weak spreading gray hairs up to ± 0.5-0.7 mm with many shorter, grossly bulbous-based setules, the lfts much differentiated dorsoventrally, the blades strongly revolute, densely pilosulous along the midrib beneath.

    Stipules weak setiform 4-8 mm, early caducous.

    Lvs spreading-ascending 2.5-5.5 cm; pulvinus moderately dilated 1.5-2.5 mm; petiole 6-12 mm, at middle 0.7-1 mm diam, obscurely sulcate ventrally; rachis 5-32 mm; lfts 2-6 pairs, ascending from rachis face upward on slightly dilated pulvinule 0.4-0.9 mm, commonly accrescent upward, in outline narrowly elliptic or elliptic-oblanceolate, 9-24 x (2.5-)3-7 mm. at base subsymmetrically cuneate, at apex abrubtly contracted into a weak (often deciduous) pilosulous acumen 0.5-1.2 mm, the blades firmly membranous, when dry nigrescent and glossy above, dull brown and minutely bulbous-setulose beneath, the midrib above impressed- canaliculate, beneath prominent cordlike, densely pilosulous, the 4-8 pairs of very slender secondary veins faintly raised on both faces, tertiary venulation imperceptible.

    Pedicels 2.5-3.5 cm, like the sepals densely gray-pilosulous, bracteolate 4-5 mm below calyx; bracteoles lanceolate cymbiform 6.5-8 mm caducous; buds ovoid, acute, pilosulous and setulose; sepals 10-11 mm, the outer firm, broadly lanceolate, the inner oblong-oblanceolate membranous-marqined; petals yellow, heteromorphic, the adaxial one largest, broadly cuneate- flabelliform 17x11 mm, three ±13 mm, 2 of them oblanceolate x 6 mm, 1 obovate x 9 mm, the fifth ± 11.5 mm, dimidiately obovate, coiled over androecium; ovary gray-pilosulous; style 6.5 mm, linear; ovules ± 5.

    Pod oblong, ± 2.5-3 x 0.8 cm, the nigrescent valves gray-puberulent and minutely viscid-setulose; seeds unknown. — Collections: 3.

    Sandy rock ledges near or above 1200 m, local, known only from the southernmost spurs of Sa. do Espinhago near the Minas Gerais-Rio de Janeiro boundary (Sas. Negra and Ibitipoca). — Fl. II—VI.

    Serras Negra and del Ibitipoca, situated at 43° 55' W, 21° 45' and 21° 58' S near the boundary between the states of Rio de Janeiro and Minas Gerais, are isolated heights rising to 1760 m near the confluence of the transverse Serra da Mantiqueira and the vertically aligned axis of Serra do Espinhaço. In the southernmost spurs of the latter mountain system C. cathartica, as shown above, has undergone substantial morphological fragmentation, and it seems likely that C. catharticoides is a detached terminal product of this line of differentiation. With the floral structure of C. cathartica sens. lat. it closely resembles in habit, in paucifoliolate leaves, and in short broad pod those races of C. cathartica var. paucijuga found immediately northward in the serras around Barbacena and Sao Joao del Rei, but differs greatly from all of them in the form of the leaflets. These, instead of being flat and slenderly costate, are strongly inrolled marginally, with stout midrib so far depressed ventrally and so prominent dorsally as to divide the blade above into two convex and beneath into two concave halves. The dense gray pubescence of the costa beneath furnishes a visually arresting but perhaps unimportant differential character. In general aspect the foliage of C. catharticoides resembles that of C. paniculata, though lacking the dilated wing of the leaf-stalk and combined with an entirely different inflorescence and flower. Collected first in 1821 by Auguste de Saint Hilaire (no. D/75, P).