Monographs Details: Mimosa fonticola 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 fonticola Barneby
Synonyms:Mimosa dolens Vell.
Description:Species Description - Erect virgate subshrubs of unknown height (6 + dm), unarmed eglandular, the terete striate, densely leafy stems, lf-stks and peduncles densely villosulous and hispid with mixed short gray hairs and spreading-ascending rufous setae to 1-2 mm, the foliage bicolored, the firm lfts when dry dull brown above, leaden-gray beneath, loosely strigose on both faces, finely continuously callous-marginate and ascending-setose-ciliate, the inflorescence a simple efoliate indeterminate pseudoraceme of solitary globose capitula exserted to 2(-?) dm beyond foliage. Stipules firm ascending, narrowly lanceolate ±5 7 x 0.5 mm (lower lvs unknown); pinnae 1-jug., the rachis ±3.5 cm, the interfoliolar segments 1.5-3 mm; lfts 12-15-jug., the small first pair close to subulate paraphyllidia ±1.5 mm, thence scarcely graduated, the blades oblong-elliptic from semicordate base, abruptly acuminulate, those at mid-rachis 8-10.5 x 2.7-3.3 mm, ±3 times as long as wide, the marginal nerve ±0.1 mm thick, the ascending cilia mostly less than 1 mm, the blades all nerveless above, faintly 1-nerved beneath by the slightly displaced midrib. Peduncles at anthesis 3-8 mm; capitula without filaments ±9 mm diam., prior to anthesis conelike, the glabrous fl-buds concealed by imbricate oblance-elliptic hispid-ciliate bracts ±4 mm; flowers 4-merous 4-androus; calyx obsolete; corolla narrowly vase-shaped 3.3 mm, the ovate concave, scarcely thickened lobes ±0.7 x 0.5 mm, 1 -nerved dorsally, glabrous; filaments (probably pink) free to base, exserted 4.5 mm; ovary before fertilization glabrous; pod unknown.

Distribution and Ecology - In unrecorded habitat, known only from the above-cited locality in upland e. S. Paulo.—Fl. I(-?).

Discussion:

The plant provisionally described as M. fonticola is in the earliest stage of anthesis and insufficient as a basis for formal description. It was mistaken by Glaziou for M. dolens, but is unarmed and eglandular, and has a long, apparently indeterminate virgate inflorescence of a type usually associated with a craspedially dehiscent fruit. Its characters are given here in detail in order to draw attention of Brazilian botanists to the existence of an undescribed mimosa in need of study in the field. It bears a strong likeness in most characters to the Paraguayan M. custodis, but has developed leaf-stalks, one-nerved leaflets, and very short peduncles. Mimosa dolens var. latifolia is also similar except in the determinate inflorescence.

Distribution:Brazil South America| São Paulo Brazil South America|

Narratives:Mimosa fonticola