Monographs Details: Mimosa nycteridis 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.
Family:Mimosaceae
Synonyms:Mimosa trichocephala Benth.
Description:Species Description - Rank, erect or scrambling, openly branched shrubs to 2 m, the terete stramineous stems and lf-stks either simply minutely puberulent or both puberulent and hispid with erect rufescent setae to 1-1.5 mm, the stems in addition armed with scattered recurved broad-based intemodal aculei to 1-2.5 mm, the back of pinna-rachises always ascending-hispid but unarmed, the thin-textured lfts bicolored, glabrous except for discontinuously appressed-setose margin, bright green above, pallid beneath, the solitary or 2-3-nate globose capitula both axillary on peduncle no longer than subtending lf-stk and forming either a short terminal pseudoraceme or several axillary ones. Stipules subherbaceous lanceolate incurved 2-4 x 0.6-1 mm, 1-nerved, glabrous dorsally, caducous. Leaf-stalks including livid pulvinus 1.5-4 cm, at middle 0.4-0.5 mm diam., openly grooved ventrally; spicules 0; pinnae 1-jug., the axis of each (2.5-)3-7 cm, the longer interfoliolar segments 2-6 mm, rounded dorsally, 2-sulcate and low-carinate ventrally; lfts 10-14 jug., accrescent distally, the first very unequal pair less than 1 mm distant from minute subulate paraphyllidia, the blades all narrowly oblong from obtusangulate base, at apex low-deltate apiculate, those near and beyond mid-rachis 11-24 x 2.5-5.5 mm, ±4.5 times as long as wide, the plane, when dry brittle blades delicately (4-)5 (-6)-nerved from pulvinule, the subcentric midrib 3-5-branched on each side, the nerves on either side expiring beyond mid-blade, the outer posterior ones much shorter, the whole venation scarcely prominulous on either face. Peduncles slender ±10-15 mm; capitula without filaments ±5 mm diam., prior to anthesis moriform, the 4-angulate fl-buds glabrous sublustrous; bracts linear-oblanceolate ±1.5 x 0.2 mm, keeled dorsally, thinly setulose-ciliolate; flowers 4-merous dimorphic, the lowest ones 8-androus sterile, their four longer filaments exserted 4-5 mm, spatulately dilated at tip, their four shorter ones filiform, the upper fls 4-merous bisexual, the filaments all exserted ±4 mm, tapering to the anther; calyx of all fls shallowly campanulate membranous, obscurely lobulate and minutely ciliolate, that of sterile fls 0.15-0.2 mm, that of fertile ones to 0.4 mm; corollas turbinate, those of sterile fls 1.5-1.9 mm, with lobes 0.6-0.8 mm, those of fertile fls 2.2-2.5 mm, with lobes ±0.9 x 0.4 mm, the lobes of all submembranous 1-nerved; filaments of all fls monadelphous through ±0.5 mm, lavender-pink distally. Pods (not seen fully mature) numerous in subspherical capitula, sessile, in profile narrowly oblong ± 10-14 x 3—4 mm, 4-6-seeded, the replum hispid with stout divaricate compressed tapering stramineous setae to 4-5 mm, the thin-textured valves green glabrous, presumably breaking when ripe into free-falling articles.

Distribution and Ecology - In disturbed forest at ±800 m, known only from Sa. do Morcêgo n.-w. of Formosa (an e. spur of Sa. Geral do Paranã) near 14°40'S in e.- centr. Goiás, Brazil.—Fl. III-IV(-?). Map 56.

Discussion:

 

Distribution:Brazil South America| Goiás Brazil South America| Paraná Brazil South America|