Mimosa pseudotrachycarpa 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 pseudotrachycarpa Barneby

  • Type

    151. Mimosa pseudotrachycarpa Barneby, sp. nov., hucusque in herbariis cum M. trachycarpa Bentham (quae eadem est ac M. cruenta vera) commutata, sed ab ea imprimis stipulis margine revolutis foliolisque subenerviis diversa.—Brazil. Paraná: Tamanduá, 24.XI

  • Synonyms

    Mimosa trachycarpa Benth.

  • Description

    Species Description - Stiffly branched microphyllous shrubs attaining 9-12(-?) dm, armed either close below or far below each node with one infrapetiolar and two infrastipular, straight or recurved, stout vulnerant aculei 3-5.5 mm (one or more of each triad sometimes wanting), the young stems, lf-stks and peduncles densely viscid-puberulent with minute, forwardly incurved hairs and erect gland-tipped setulae 0.1-0.2 mm tall, the foliage (dry) brown-olivaceous concolorous, the thick-textured plane lfts glabrous on ventral or on both faces, minutely ciliolate, the globose or plumply ellipsoid capitula single in primary lf-axils or in lf-axils of a succession of lateral short-shoots, forming an effuse leafy thyrse or panicle. Stipules firm ovate-deltate 1-2 x 1-2 mm, those of primary lvs spreading-recurved, ventrally convex, becoming dry deciduous, those of axillary brachyblasts smaller ascending. Leaf-stalks (1-)2-11 mm, the petiole often reduced to livid pulvinus, potentially attaining 2 mm, the interpinnal segments 0.5-4 mm, the ventral groove continuous (spicules 0); pinnae of most lvs 2-4-jug. (of some small distal lvs 1-jug., no further described), accrescent distally, the rachis of furthest pair 5-9.5 mm, the interfoliolar segments 0.4-1 mm; lfts of distal pinnae 7-12(-13)-jug., sube- quilong except at base of rachis, the first pair 0.2-1.2 mm distant from ovate paraphyllidia 0.30.5 mm, the blades oblong obtuse from semicordate base, the longer ones 2-3 x 0.85-1.2 mm, 2-3 times as long as wide, the venation immersed. Peduncles 5-30 mm; capitula without filaments ±7 x 5-6 mm, prior to anthesis moriform, the plumply obovoid fl-buds either glabrous or gray-puberulent; bracts elliptic or oblanceolate 1-1.5 x 0.3-0.6 mm, either puberulent dorsally or merely ciliolate, caducous; flowers 4-merous 8-androus, all or almost all bisexual; calyx submembranous campanulate 0.6-0.8 mm, externally either glabrous or puberulent, the broadly triangular or depressed-deltate teeth 0.1-0.25 mm, the rim microscopically ciliolate; corolla narrowly turbinate 2.1-3 mm, the membranous, shallowly concave, ovate lobes 0.7-1 x 0.8 mm, the central nerve faintly branched; filaments lilac-pink, united at very base into a stemonozone below the ovary, exserted 4-5.5 mm; pod not seen.

    Distribution and Ecology - In dry stony campo and at edge of gallery woodland, best known from ±700-900 m in n.- e. Paraná (Jaguariaiva, Arapoti, Ponta Grossa), Brazil; not reported from Sta. Catarina (Burkart, 1979), but reappearing near 700 m in n.-e. Rio Grande do Sul (mun. Vaccaria).—Fl. IX-XII(- ?).

  • Discussion

    The type-collection of M. pseudotrachycarpa was misidentified by Dusen as M. trachycarpa Bentham, a name that is here interpreted as a synonym of M. cruenta Bentham. From the latter it is clearly different in strongly or at least incipiently revolute stipules and in almost nerveless leaflets.

  • Distribution

    Brazil South America| Santa Catarina Brazil South America| Rio Grande do Sul Brazil South America| Paraná Brazil South America|