Chamaecrista desvauxii var. circumdata

Title

Chamaecrista desvauxii var. circumdata

Authors

Howard S. Irwin, Rupert C. Barneby

Scientific Name

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

Description

1d. Chamaecrista desvauxii (Colladon) Killip var. circumdata Irwin & Barneby, var. nov., a var. mollissima, cum qua foliolorum ambitu adspectuque toto bene convenit, foliolis subcoriaceis nervo marginali crasso cartilagineo albicanti circumdatis, a var. langsdorfii imprimis foliolis late ellipticis 6-8 (nec 2-6) mm latis multo crassius marginatis diversa.— BRAZIL. Bahia: ±45 km w. of Vanderlei along BR-242 (near 12°S, 44°30'W, 7.IV. 1976 (fl, fr), G. Davidse, T. P. Ramamoorthy & D. M. Vital 12040.—Holotypus, US = NY Neg. 10495.

Glabrous throughout, the foliage dull olivaceous, the stiffly chartaceous lfts paler beneath, all margined with a pallid cordlike nerve 0.25-0.4 mm diam; stipules 9-16 x 6-9 mm, a little shorter than the internodes, at apex obtusely deltate, persistent; lf-stalk stout 4.5-5.5 mm; gland 0.7-0.9 mm diam, obscurely stipitate, broader than tall; larger lfts ±20-24 x 6—8 mm; pedicels 25-30 mm; longer petals ±16 mm; ovules 12.—Collections: 1. Cerrado, in sandy soils near 800 m, known only from the type-locality in the middle Rio São Francisco valley in n.-w. Bahia.—Fl. II-IV.

This striking variant on the theme of Ch. desvauxii resembles the glabrous state of var. mollissima in general aspect and in the broadly elliptic outline of the leaflets, but these differ in their stiff texture and in the pallid nerve that forms a blunt raised rim around the blade. Occasional leaflets of var. langsdorfii show a similar but less pronounced marginal thickening, but are then of substantially narrower outline.