Monographs Details: Cassia cathartica Mart. var. cathartica
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
Synonyms:Cassia cathartica Mart., Cassia hirsuta L., Cassia pachycalyx Vogel, Cassia cathartica var. angustifolia Benth.
Description:Species Description - Primary lvs 6-16 cm; petiole 6-22(-25) mm; rachis mostly 6-14 cm; lfts of subuniform size or commonly a little decrescent distally, in outline oblong- or lance-elliptic to ovate or oblong-ovate, rarely narrowly oblong, mostly obtuse and mucronulate, sometimes subacute or emarginate, the larger ones 8-21 (-24) x (2-)3.5-8.5 mm. — Collections: 136.

Distribution and Ecology - Campo, cerrado, in red sandy clay, quartzite, and ferruginous soils, widespread and locally abundant at 900-1300(-1500) m in Serra do Espinhapo, Minas Gerais, from near Grao Mogol and Montes Claros (near 15° 30' S) s. to the n. foot of Serra de Mantequeira, w. around the headwaters of R. Sao Francisco into the Triangulo Mineiro and (rarely) to n.-w. Minas (Sa. das Araras) and s.-w. and s.-centr. Goia^ (Sas. dos Cristais and Dourada), s.-e., still locally abundant (but depleted by destruction of the campo) and descending to 600 m, through n.-w., w.-centr. and s.-e. Sao Paulo into the n.-e. corner of Parana (mun. Jaguariaiva and Ortigueira, near 24° S), formerly cultivated as a purgative herb and collected, probably as an adventive, in the lowlands of e.-centr. Bahia (Cruz das Almas). — Fl primarily X—VI, but sporadically through the year.

Discussion:

Variation in var. cathartica appears partly clinal, partly sporadic. The largest leaves and amplest leaflets are found mostly at relatively low elevations in Sao Paulo and Parana,the smallest and narrowest (var. angustifolia Benth.) toward the variety's northwestern limit; but the extremes are connected by an uninterrupted series. The typus of C. taubertiana represents a form in which many or most uppermost leaves are reduced in size, giving rise to a relatively showy, because less leafy, panicle. In general, relatively large leaves and large flowers go hand in hand, but the correlation is imperfect. An example of marked intra- populational variation in flower size was collected on Morro das Pedras northeast of Patrocinio in western Minas (Irwin & al 25849); here, among many plants that would be considered normal var. cathartica in Serra do Espinhapo was a self-perpetuating strain notable for the exceptional amplitude of the f label late adaxial and abaxial petals, the latter reaching a length and width of about 2.5 cm. Flowers of equal size occur in uniform populations southward.

Most of the early synonymy of var. cathartica, already tentatively established by Vogel (1837) and confirmed by Bentham (1870, 1871) requires no comment. The still controversial C. aprica Veil., referred here by Bentham, is mentioned in Appendix I.

Distribution:Minas Gerais Brazil South America| Goiás Brazil South America| São Paulo Brazil South America| Paraná Brazil South America| Bahia Brazil South America| Brazil South America|