Monographs Details: Mimosa dicerastes 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 papposa Benth.
Description:Species Description - Arborescent shrubs with knotty defoliate trunks and branches, the densely foliate homotinous stems armed at all nodes with a pair of spreading, erratically up- or down-curved, subterete stramineous aculei to ±(1.5—)2—5 mm long and near base 0.4-1 mm diam., the homotinous stems, lf-stks and peduncles densely strigose-pilose with slender tapering brownish setae to ± 1.5—2 mm, the firm crowded, subconcolorously gray-olivaceous lfts finely densely puberulent on both faces and some proximal ones in addition dorsally appressed-setulose, the peduncles solitary in axils of coeval or immediately hysteranthous lvs, at early anthesis forming a condensed pseudoraceme hardly longer than wide, but this perhaps longer in fruit. Stipules erect firm linear-attenuate 5-7 x 0.3-0.5 mm, caducous before full expansion of associated lf. Leaf-stalks including hard pulvinus 4-11 mm, indistinctly sulcate; pinnae 1-jug., the rachis of each (3-)3.5-7.5 cm, rounded dorsally, carinate ventrally and shallowly excavate laterally between successive pairs of pulvinules, these to 1-2 mm apart; lfts 34-45- jug., decrescent toward each end of rachis but more gradually so distally, the small unequal first pair less than 1 mm distant from pulvinus (paraphyllidia 0), all in outline narrowly lance-oblong from shallowly semicordate base, acute or abmptly apiculate at apex, straight or obscurely arched forward, those near mid-rachis (4-)5-8.5 x 1-2 mm, 4-5 times as long as wide, veinless on upper face, beneath faintly 3-(4)-nerved from pulvinule, the midrib displaced to divide blade ±1:3, the inner posterior nerve produced almost to blade apex, the outer 1 (-2) shorter. Peduncles 15-25 mm; capitula subglobose, without filaments 6.5-7 mm diam., prior to anthesis moriform, the 4-angulate fl-buds minutely papillate-puberulent at apex; bracts linear-spatulate 1.8-2.3 x 0.3-0.4 mm, glabrous and keeled dorsally, the dilated tip setulose-ciliolate; flowers 4-merous 4-androus, only a few distal ones bisexual, the lower staminate and smaller; calyx paleaceous 1.5-2.3 mm, cleft to within ±0.5 mm of base into four setose-decompound lobes; corollas accrescent upward through capitulum, 2.6-3.4 mm, the tube narrowly funnelform, the reddish, callous-thickened cymbiform lobes 0.75-0.9 x 0.5-0.6 mm; filaments pink, monadelphous through ±1 mm, exserted 5-6 mm; pod unknown.

Distribution and Ecology - In campo rupestre, 1000-1250 m, known only from Chapada dos Veadeiros at points 22-25 km n. and 30 km w. of Alto Paraíso, near 14°S in e.- centr. Goiás, Brazil.—Fl. III-V(-?).



Distribution:Brazil South America| Goiás Brazil South America|