Mimosa pyrenea

  • Title

    Mimosa pyrenea

  • Authors

    Rupert C. Barneby

  • Scientific Name

    Mimosa pyrenea Taub.

  • Description

    399. Mimosa pyrenea Taubert, Bot. Jahrb. Syst. 21: 430. 1896.—"Habitat in montibus Serra dos Pyreneos: Ule n. 2854—Flor. m. Aug."— Holotypus, +B; no isotypus found at HBG or K in 1984; probable isotypi, Ule 102 in hb. Glaziov., P! R!—Ule 2852, HBG! may be an isotypus misnumbered.

    M. concinna Bentham, Trans. Linn. Soc. London 30: 404. 1875, nom. illeg. & in Martius, Fl. bras. 15(2): 337, descr. ampliat. 1876.—"Habitat ad Corego de Feragua [=Jeraguá, 15°45'S, 49°20'W], provinciae Goyaz: Burchell n. 7445; Pohl; ad Rio Maranhão [±14°05'S, n.-e. of Goianesia] ejusdem provinciae: Burchell n. 7563."—Lectotypus, Burchell 7563, K (hb. Hook.)!; isotypus, GH!; syntypi, Pohl 1210, W (sterilis)! Burchell 7445, K! =M. virgula Barneby.— Non M. concinna Willdenow, 1806.

    M. loeseneriana Glaziou, Bull. Soc. Bot. France 53(Mém.3b): 183. 1906 ex parte, nom. nud.—"Serra Dourada et Serra do Arruda, Goyaz, [Glaziou] 21050 [exclus. 21050a, quae = M. xanthocentra subseri- cea].’’-Specimina authent., +B = F Neg. 1419! K! P! M. pyrenea Glaziou, 1906: 184, nom. nud.—"Corumbá, dans le campo, Goyaz, n° 21051.''''—Specimina authent., C! G! K! M! P! S!

    Slender erect subshrubs from knotty xylopodium, the simple or distally few-branched stems attaining 7-12 dm, at base 2-4 mm diam., in age brittle and proximally defoliate, densely strigose throughout, like the broad stiff pinna-rachises, with appressed tapering setae, these to ± 1 mm long below the inflorescence, longer and silky-flagelliform distally, the very numerous and small, coriaceous, subvertically imbricate lfts facially glabrous, setulose only around thick stramineous margin, the loose open pseudoracemes of globose capitula usually bracteate by diminished lvs, these distally shorter than the subtended peduncle or subobsolete. Stipules erect firm, lanceolate or linear-attenuate 3-6.5 x 0.5-1 mm, dorsally strigose, glabrous within, persistent. Leaf-stalks at and below mid-stem not over 4 mm including pulvinus, that of distal or sometimes of all lvs essentially 0; pinnae 1-jug., their rachis in lvs below inflorescence 4.5-9(-10) cm, rounded dorsally, ventrally carinate between excavated interfoliolar sulci, the longer interfoliolar segments 0.5-1 mm; lfts of longer pinnae 55-90-jug., slightly decrescent at each end of rachis, the first pair close to pulvinus and subequilong, those toward mid-rachis linear-oblong or narrowly lance-elliptic from obtusely semicordate base, apiculate at apex, to 3-6 x 0.7-1.2 mm, 3.3-5.5 times as long as wide, on upper face pruinose, on lower face 5-6-nerved from pulvinule, the midrib subcentric or forwardly displaced to divide blade 1:2, the primary nerve on each side of midrib produced nearly to blade apex, the posterior ones shorter, the 1-seriate setulae of margin free for 0.1-0.6 mm and subappressed. Peduncles solitary 10-28 mm; capitula without filaments 7.5-9 mm diam., prior to anthesis moriform, but the 4-carinate, minutely papillose-puberulent fl-buds sometimes no longer than filamentous flagelliform cilia of bracts, these linear-oblanceolate ±2.5 x 0.4-0.5 mm, dorsally glabrous, ciliate; flowers 4-merous 4-androus, some lower ones smaller and staminate; calyx paleaceous 2.2-3 mm, 4-cleft to below middle into deeply setiform-decompound lobes; corolla narrowly funnelform 3.1-3.7 mm, the thick-textured cymbiform, dorsally pallid-carinate lobes 1-1.4 x 0.6-0.8 mm; filaments monadelphous through 0.8-1.8 mm, exserted 5-7 mm. Pods ±3-10 per capitulum, sessile, piano-compressed, when well fertilized 3(-4)-seeded, in profile oblong, undulately constricted between seeds, attaining 20-25 x 5-6 mm but by abortion of ovules shorter, sometimes broadly elliptic 1-seeded, the forwardly appressed-setose replum 0.4-0.5 mm wide, the papery valves hispid-pilose with ascending, simply tapering or flagelliform, scaberulous setae 1-2.5 mm; dehiscence as in M. venatorum, seeds not seen.

    In stony or sandy campo, sometimes at the gallery-brejo interface, 800-1000 m, known only from Sas. dos Pirineus and Dourada in s.-centr. Goiás, Brazil.-Fl (I-)IV-VIII.