Monographs Details: Mimosa heringeri Barneby
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.
Synonyms:Mimosa setosissima Taub., Mimosa decorticans Barneby
Description:Species Description - Unarmed, amply microphyllidious shrubs and treelets attaining 2.5—4 m with trunk 8 cm diam., the ascending branches densely clad distally with crowded, narrowly ascending lvs, proximally defoliate and following prompt exfoliation of epidermis forming a framework of naked cinnamon-brown stems ±2.5-9 mm diam., the cauline and foliar axes strigose-hispid with forwardly subappressed tapering setae to 1-1.5 mm mixed with subsessile or short-stalked glands, the brownish-olivaceous, moderately lustrous lfts facially glabrous or dorsally puberulent, ascending-setulose- or glandular-ciliolate, the peduncles solitary axillary or passing upward into a short condensed, scarcely emergent pseudoraceme of ellipsoid capitula. Stipules broadly lanceolate to 10x3 mm, the firm blades early dry caducous. Leaf-stalks 4.5-18 cm, low-convex dorsally, narrowly continuously sulcate ventrally (spicules 0), the petiole including or reduced to the obese livid pulvinus 4.5-8(-15) mm, 1-3 mm diam., the longer interpinnal segments of distally tapering lf-stk 6-10 mm; pinnae (5—)7—18-jug., proximally decrescent, the axis of longer ones 4-7 cm, the longer interfoliolar segments 1-2 mm; lfts of longer pinnae 31-57-jug., markedly decrescent proximally and less so distally, the blades narrowly oblong obtuse or subapiculate, the larger ones 3.5-5.5 x 1—1.3(—1.5) mm, all lustrous smooth above, prominulously 3-nerved beneath, the centric midrib with 1-2 secondary venules. Peduncles mostly solitary 5-8 cm; capitula without filaments 10-13 mm diam., prior to anthesis moriform or incipiently conelike; bracts oblanceolate 2.5-4 mm, dorsally setose and stipitate- glandular; flowers 4-merous 8-androus, some proximal ones staminate but scarcely smaller; calyx ±0.5 mm, its subtruncate orifice ciliolate with fine, at times partly gland-tipped setulae 0.6-1 mm; corolla 4.8-5.4 mm, the ovate 1-nerved lobes 1.2-1.5 mm, densely appressed-setulose dorsally; filaments pinkish-lavender fading whitish, monadelphous through 0.5-0.6 mm, exserted to 9-17 mm. Pods 1-3 per capitulum subsessile, in profile broadly linear-oblong 45-55 x 10-11 mm, the replum ±1.5 mm wide, the convex valves consisting of livid exocarp ±0.05 mm and crustaceous endocarp to 0.2 mm thick in section, the replum and valves alike densely hispid-strigose and viscid with forwardly ascending bulbous-based setae intermingled with subsessile or short-stipitate glands, the valves when ripe separating entire from replum and falling in one piece; seeds ±7-9, transverse, plumpy obovoid 5-6 x 4.5 mm, the testa lustrously castaneous.
Distribution and Ecology - In moist stony soils of brejo and on creek- banks, 950-1100 m, known only from the sources of Ribeira do Gama immediately to the s. and s.-w. of the city of Brasília, in Distrito Federal, Brazil.-Fl. II-V(-VIII).
Closely akin to M. setosissima and M. decorticans; for comment see under the former. This handsome species is dedicated to Dr. Ezechias Paulo Heringer (IBGE, Brasília), whose numerous, judiciously chosen, beautifully prepared and widely distributed collections of planaltine Mimosae have provided invaluable information on the morphology and dispersal of the genus.
Distribution:Brazil South America
| Distrito Federal Brazil South America