Monographs Details: Cassia nanodes H.S.Irwin & Barneby
Authors:Howard S. Irwin, Rupert C. Barneby
Authority: Irwin, Howard S. & Barneby, Rupert C. 1978. Monographic studies in Cassia (Leguminosae, Caesalpinioideae). III. Sections Absus and Grimaldia. Mem. New York Bot. Gard. 30: 1-300.
Family:Caesalpiniaceae
Description:Latin Diagnosis - Cassia nanodes Irwin & Barneby, sp. nov., statura pygmaea C. ciliolatam simulans ac ei verosimiliter affinis, sed foliis magis heteromorphis, petiolo breviori (3-6 nec 5-18 mm), alabastris ellipticis obtuse apiculatis nec globosis, antherisque muticis ut videtur satis absimilis.

Species Description - Diminutive undershrubs with slender simple few-lvd stems arising annually from a xylopodium, 8-17 cm tall, except for the glabrous concolorous faces of the small setose-ciliolate lfts in all parts minutely viscid-puberulent and also hispid with yellow setae up to 1-1.8 mm, the terminal simple few-fld racemes immersed in foliage or very shortly exserted. Stipules erect, subulate or lance-subulate, 1.5-3 mm, persistent. Lvs flexuously ascending, heteromorphic, the lowest much shorter and simpler than the median and upper ones, (1-) 1.5-8 cm, shortly petioled; pulvinus scarcely differentiated, up to 1 mm; petiole 3-6 mm, at middle openly shallow-sulcate, 0.3-0.55 mm diam; rachis of lower lvs 0.3-3 cm, of the rest 3-7 cm; lfts of sub-basal lvs 2-6, of median and upper ones 7-16 pairs, slightly decrescent upward, all divaricate from rachis and resupinately tilted, edgewise to meridian, distal margin up, on scarcely dilated, spirally wrinkled, ventrally sulcate pulvinule ±0.5 mm, in outline elliptic or obovate-elliptic obtuse, (3-)4-11 x (1.5-)2-6.5 mm, minutely mucronulate, at base on adaxial side cuneately decurrent to the rachis, on abaxial side broadly cuneate to sub- cordate, the entire margin plane, setulose -ciliolate, the blades on both faces dull brownish-olivaceous glabrous, perhaps in age glaucescent, the venation except for the slender, dorsally prominulous midrib immersed. Racemes terminal simple 3-16-fld, the axis up to 5.5 cm, usually less, the 1-2 simultaneously expanded fls raised to level of buds; bracts spreading lance-subulate 2-2.5 mm, persistent; pedicels subfiliform 13-24 mm, bracteolate 4-9 mm below calyx; bracteoles subulate 0.8-1.4 mm, persistent; buds ellipsoid, bluntly apiculate by the cucullate tip of outermost sepal, microscopically viscid- puberulent and thinly setose; sepals subpetaloid, the outer reddish, lance-ellipsoid, obtuse, 8-8.5 x ± 3 mm; petals narrowly ascending, the four plane ones obovate-cuneate, only slightly unequal, 10.5-12.5 x 6-9.5 mm, the fifth falcately semi-ovate and coiled; ovary shaggy-setose; ovules 6-7. Pod (seen only immature) linear-oblong, ±2.5 cm, the reddish valves both puberulent and hispid with yellow setae up to ± 2 mm. - Collection: 1. Plate 10.

Distribution and Ecology - Campo, probably near 1200 m, known only from the w. boundary of Distrito Federal with State of Goias, in drainage of Rio Corumba near lat. 16° S. — Fl. X-XI.

Discussion:

The type-collection of Cassia nanodes was distributed by Glaziou as C. ciliolata, the identification probably attributable to Harms. The two species are no doubt closely related. However they differ importantly in the flower, C. nanodes having elliptic bluntly apiculate flower-buds and muticous anthers, wheras C. ciliolata has globose buds and mucronulate anthers, the difference in shape of buds being a function of relatively broader and narrower sepals. The stem pubescence of C. ciliolata is variable, but hispid-setose only in var. pulchella, which is endemic to southern Serra do Espinhaço, thus remotely distant from C. nanodes. The forms of C. ciliolata known to occur in western Minas Gerais have much shorter pubescence, not only on the stems but also throughout the inflorescence and on the pod. There appears to be some difference in the ontogeny of the raceme, only one or two flowers simultaneously reaching full anthesis in C. nanodes, several in C. ciliolata.

Distribution:Goiás Brazil South America| Brazil South America|

Narratives:Cassia nanodes