Mimosa debilis var. vestita (Benth.) 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

  • Scientific Name

    Mimosa debilis var. vestita (Benth.) Barneby

  • Type

    326d. Mimosa debilis Humboldt & Bonpland ex Willdenow var. vestita (Bentham) Barneby, comb. nov. M. rixosa var. (?) vestita Bentham, J. Bot. (Hooker) 4: 362. 1841.-"[e] Rio Janeiro [misit] Langsdorff."—Holotypus, Riedel 52 (vix florens), collected at Cuia

  • Synonyms

    Mimosa rixosa var. vestita Benth., Mimosa platyphylla Benth.

  • Description

    Variety Description - Subshrubs at first erect from xylopodium, with stems solitary or few and wandlike, simple or strictly few-branched distally, nowhere aculeate, including the leafless or depauperately leaf-bracteate pseudoraceme (6—)8—12 dm but sometimes in age frutescent and attaining 2(-2.5) m, densely hispid or loosely strigose with smooth or subscaberulous setae to 0.6-1.5 mm mixed with minute puberulence (exceptionally glabrate), the lfts usually setose on both faces, sometimes (in Bolivia) beneath only, then either glabrous or puberulent above, the inflorescence (fresh) sometimes clammy to touch but eglandular; leaf-stalks 6-35(-45) mm; distal pair of lfts obliquely obovate 2-5(-5.5) x l-2.6(-3) cm; capitula without filaments 4.5-6.5 mm diam., prior to anthesis conelike, the bracts 1.5-3.5 mm, dorsally sericeous or puberulent, setose-ciliolate; pods 11— 20 x 4-4.5 mm, the valves concealed or almost so by a dense mane of tapering setae to 2.5—4 mm.

    Distribution and Ecology - In low, often seasonally wet places in campo cerrado or open shrub-woodland, sometimes colonial on roadsides, ±250-500 m, locally plentiful on both slopes of the Paraguai-Guaporé watershed, from the Pantanal in Mato Grosso do Sul and s. Mato Grosso w. to Sta. Cruz and adj. Beni, Bolivia.—FL. II-VI(-?). Map 53.

  • Discussion

    The var. vestita has been set off from polymorphic var. debilis principally by the precarious character of unarmed stems, but the growth-habit, more evident in the field than in the herbarium, is clearly different. Near Cuiabá I saw var. debilis (Anderson 11343) and var. vestita (Anderson 11346, both NY) growing together, and at the time it did not occur to me that they could represent forms of one species. Despite a distinct growth-form, var. vestita is otherwise variable in detail. Around the margin of the Pantanal in Brazil the foliage is densely pubescent, the capitula are silky and conelike prior to anthesis, and the cauline setae are minutely scaberulous. In Bolivia the foliage tends to be more thinly pubescent or even glabrescent while the capitula remain silky, but the cauline setae are often smooth. Less than half the known specimens of var. vestita have grown pods, and it would be premature to claim that the long dense indumentum of the valves will prove a constant feature of the variety.

  • Distribution

    Brazil South America| Mato Grosso Brazil South America| Mato Grosso do Sul Brazil South America| Bolivia South America| Beni Bolivia South America| Santa Cruz Bolivia South America|