Cassia itabiritoana

  • Title

    Cassia itabiritoana

  • Authors

    Howard S. Irwin, Rupert C. Barneby

  • Scientific Name

    Cassia itabiritoana H.S.Irwin & Barneby

  • Description

    99.  Cassia itabiritoana Irwin & Barneby, sp. nov., habitu, foliolorum numero formaque ac inflorescentia C. adenophyllae similis et forsan propiuscule affinis sed robustior, petiolis validioribus 2-4 (nec 0.8-2) cm longis, pedicellis elongatis 2.4-4 (nec 1.6-2.1) cm longis, floribus majoribus (sepalibus 11-14 nec 6-8 mm, petalis 12-15 nec 8.5-10 mm longis) primo intuitu distinguenda. - BRAZIL. Minas Gerais: Serra do Itabirito ±45 km s.-e. of Belo Horizonte, near 1600 m, 12.11.1968 (fl, fr), Irwin, Maxwell & Wasshausen 19874. — Holotypi UB; isotypi, C, F, GH, K, NY, RB, S, US. - Plate 13.

    Shrubs of rounded outline 1.5-2.5 m, with several black primary stems paniculately branching and leafy distally, the young growth patently hirsutulous and setulose throughout, the stems of the season, lf-stalks, and inflorescence very densely so, moderately viscid, the foliage more thinly so, green, the terminally racemose inflorescence scarcely exserted.

    Stipules erect or at length recurved, narrowly subulate, 1-2 mm, pallid, persistent.

    Lvs arcuately ascending, 6-14 cm, petiolate; pulvinus moderately dilated, discolored, 1.5-2.5 mm; petiole (1.5-)2-4 cm, tapering from a broad base, narrowly sulcate ventrally; rachis 2-7 cm; lfts 3-5 pairs, tilted a little forward from the rachis on oblong, ventrally canaliculate pulvinule 1.5-2.5 mm, not or feebly imbricate when pressed, scarcely graduated in size, in outline amply elliptic- obovate, obtuse but mucronulate by the excurrent costa, (1.3-)1.7-3.8 x 0.7-1.7 cm, at asymmetric base rounded at both sides, the blades firmly chartaceous, dull olivaceous, concolorous, on both sides inconspicuously papillate and villosulous with fine erect hairs mixed with scattered setules, the margins entire or minutely gland-crenulate, plane or subrevolute, the costa and 4-5 pairs of secondary veins almost immersed above, prominulous beneath but very slender, the reticualtion invisible.

    Inflorescence terminal to branchlets, shortly but loosely racemose, the fls at anthesis about at level of the buds, the axis including peduncle 5-8 cm; bracts submembranous, yellowish, sometimes brown in age, narrowly lance-subulate, 2-3 mm, perisitent or tardily deciduous; pedicels ascending (2-)2.4-4 cm, bracteolate (0.5-) 1-3.5 mm below calyx; bracteoles resembling bracts but only 1-1.5 mm, persistent; buds ovoid, subacute, densely villosulous and setulose; sepals ovate or ovate-elliptic, obutse to subacute, 11-14 mm x 4-5.5 mm, the inner ones with broad petaloid margins; petals yellow, up to 1 mm longer than the sepals, 4 broadly oblanceolate to flabellate-cuneate 5-9 mm wide, the fifth thickened at base, falcately convolute; ovary viscid villosulous and setulose; ovules 5-7.

    Pod oblong, 2.5-3 x 0.7-0.75 cm, the stiffly chartaceous, purplish-green valves densely viscid- villosulous and purplish-setulose; seed unknown. — Collections: 3.

    Steep rocky slopes, 1050-1750 m, locally common, known only from the upper slopes of Sa do Itabirito, Minas Gerais. — Fl. I-III.

    A bushy cassia of marked individuality, resembling in many technical details the distantly allopatric C. adenophylla, but readily distinguished by the generally coarser habit of growth, the longer petiole and ampler leaflets, and the long-pedicellate, much larger flowers.