Chamaecrista desvauxii var. peronadenia

  • Title

    Chamaecrista desvauxii var. peronadenia

  • Author(s)

    Howard S. Irwin, Rupert C. Barneby

  • Scientific Name

    Chamaecrista desvauxii var. peronadenia H.S.Irwin & Barneby

  • Description

    1b. Chamaecrista desvauxii (Colladon) Killip var. peronadenia Irwin & Barneby, var. nov., adspectu toto et praesertim stipulis magnis obtusis var. glaucae (Hassler) Irwin & Barneby praesimilis sed glandula petiolari parvula eximie stipitata 1.5-2.4 mm usque longa foliolisque rachi valde abbreviato subpalmatim dispositis diversa.—BRAZIL. Goiás: frequent among sandstone rocks about summit of Sa. Dourada, 800 m, 20 km s.-e. of Goiás Velho, 18.I.1966 (fl, fr), Irwin, Souza & Reis dos Santos 11696.—Holotypus, UB; isotypi, F, GH, K, LE, NY, RB, S, US.

    Foliage glabrous; larger stipules forwardly imbricated or nearly as long as intemodes, obovate obtuse up to 10-21 x 6-14 mm; lf-stalk of larger lvs 5-8 mm, the rachis only 1-1.5 mm; gland urceolate 0.4-0.7 mm diam, slenderly stipitate, in profile pin- or slenderly trumpet-shaped 1.5-2.4 mm tall, at least 1 mm longer than diam of head; larger lfts cuneate-obovate obtuse up to 15-27 x (7—)9—16 mm; pedicels 17-26 mm, ± as long as lf; longest sepal 14-18 mm; longer petals 16-20 mm; pod (little known) ±40 x 7 mm, glabrous or sparsely ciliolate along sutures; ovules 14-18.—Fig. 2 (petiolar nectary).

    Stony slopes in cerrado and about sandstone outcrops, locally abundant on caprock of Sa. Dourada near 800 m, known only from the type-locality s.-e. of Goiás Velho near 50°W, 16°15'S in s.-centr. Goiás.—Fl. XII-II.

    A striking variation on the theme of var. glauca, notable for the pin-shaped gland whose stipe is two to three times as tall as its head (whence the epithet) and for the subpalmately disposed leaflets separated by a rachis only 1-1.5 mm long. The var. latifolia, similar in the gland, has the habit, stipules and foliage of var. desvauxii and, like var. pirebebuiensis, which has the foliage of var. langsdorfii, is interpreted as a parallel but independent mutant. Additional material of var. peronadenia, all from the summit of Sa. Dourada (NY): 10.I.65 (fl) Heringer 10857; 18.XII.68 (fl), Harley & Barroso 11320 = Barroso et al. 790.