Monographs Details: Mimosa setosa subsp. setosa var. rupigena
Authors:Rupert C. Barneby
Authority: Barneby, Rupert C. 1991. Sensitivae Censitae. A description of the genus Mimosa Linnaeus (Mimosaceae) in the New World. Mem. New York Bot. Gard. 65: 1-835.
Description:Variety Description - Puberulent throughout but only thinly hispid with plain setae, eglandular below the stipitate-glandular pod; lf-stks 6-9 cm, the pinnae 5-8- jug., the lfts of longer ones 30-3 5-jug., puberulent overall, finely remotely setose-ciliolate; calyx of var. setosa (±2.5 mm); corolla-lobes setose eglandular.
Distribution and Ecology - About rock-outcrops near crest of Sa. do Espinhaço at 1200 m, known only from municipio Gouveia, near 18°30'S in centr. Minas Gerais, Brazil.—Fl. X-XI(-?). Map 28.
The var. rupigena may be merely a casual glandless variant of var. setosa, of which it retains the habit and pappiform calyx, but its occurrence at the far eastern periphery of the range of subsp. setosa in a specialized habitat and in a region of pronounced endemism suggests something more substantial. Further collections, obviously, are needed.
In addition to varieties of subsp. setosa formally described, I must mention two groups of aberrant specimens which deserve further study. Two collections from Chapada dos Veadeiros (Irwin 32231, 33045, distributed as M. setosa fma b, NY) have setose stem-pubescence suppressed or almost so, and corollas setulose but eglandular. These plants, from a locality at the northern known limit of the whole species’ range, were coming into flower in late March at elevations probably above 1200 m. Pods are required for positive identification. Four collections from Chapada da Contagem and vicinity in Distrito Federal (Irwin 11386, 19420, NY; Heringer 13075, NY; Kirkbride 3113, NY) are notable for leaflets of yellowish-green color coarsely 3-nerved on lower face. These have been annotated or distributed as M. setosa fma c.
Distribution:Brazil South America
| Minas Gerais Brazil South America