Mimosa artemisiana Heringer & Paula

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 artemisiana Heringer & Paula

Type

87. Mimosa artemisiana Heringer & Paula, Anais Soc. Bot. Brasil Congr. Nac. Bot. 30: (Campo Grande): 75, figs. 1, 3-7. 1979.-"E. P. Heringer 15506 . . . 5.V.1975. Crescit sponte in [Coronel Pacheco] status Minas Gerais ... in hortis culta ad Universita Br

Description

Species Description - Amply leafy unarmed trees 12-25 m with trunk 5 dm diam. and rough fissured pale yellow bark 4 mm thick, the homotinous branchlets together with all lf- and inflorescence-axes brownish-tomentellous with stellate trichomes, the thin-textured olivaceous, when dry brownish lfts minutely thinly puberulent above with mostly simple (or scattered few-branched) villi, beneath a trifle paler and sprinkled with golden glands ±0.1 mm diam., the midrib charged with stellate scales like those of stem, the lateral and terminal pseudoracemes or amply branched panicles of pliantly amentiform fl-spikes either efoliate or few-leaved at base only, commonly well exserted from foliage. Stipules linear-attenuate incurved-ascending, attaining 8-10 x 1 mm, caducous (consequently little known). Leaf-stalks 8-19 cm, the petiole including elongate pulvinus 2-3 cm, at middle 1-2 mm diam., the longer interpinnal segments 9-14 mm, the ventral groove continuous between pinna-pairs (spicules 0); pinnae 71 l(-12)-jug., decrescent proximally, the axis of distal ones 7-12.5 cm, the interfoliolar segments (2-)3-4.5 mm; lfts of longer pinnae 26-33-jug., a little decrescent at both ends of rachis, the first pair 0.5-0.8 mm distant from subulate paraphyllidia 0.4-0.9 mm, the blades subsigmoidally oblong, obtuse-mucronulate or deltately subacute, at base auriculate on posterior side, those near mid-rachis 7.5-11 x 2-3(-"5") mm, 3-4.2 times as long as wide, almost veinless above, beneath carinate by the slender prominulous subcentric, pinnately branched costa, one posterior nerve from pulvinule produced nearly to mid-blade. Flower-spikes mostly 2-4 per node of panicle, without filaments 6-8 mm diam., the axis including very short peduncle 5-12.5 cm, the fl-buds narrowly obovoid obtuse, densely ochroleucous-stellulate; bracts linear-oblanceolate 0.7-1.3 mm, stellate-tomentulose dorsally, caducous before anthesis; flowers 4(-"5")-merous 8-androus, mostly bisexual; calyx campanulate 1-1.5 mm, densely stellate-tomentulose externally, the depressed-deltate teeth 0.15-0.2 mm; corolla narrowly campanulate 2.8-4.1 mm, the erect ovate 1 -nerved lobes 0.7-1.3 x 0.6-0.8 mm; filaments white, free to base, the longer ones exserted 3.3-4.2 mm; ovary commonly puberulent, sessile. Pods (Lewis, 1987, fig. 8G) sessile linear-oblong to 8 x 1 cm and ±7-8-seeded, the valves ferrugineous-stellate-tomentulose, dehiscent as in M. schomburgkii.

Distribution and Ecology - In moist forest, sometimes in varzea, mostly below 500 m, scattered along the Atlantic slope of Brazil in lat. 16°-22°30'S, from the lower Jequitinhonha valley in s.-e. Bahia s.-w. through the basins of rios Mucurí and Doce to the s. slope of Sa. da Mantequeira in s.-e. Minas Gerais and Sa. do Camborí in Rio de Janeiro; cultivated in Brasília and Rio de Janeiro.—Fl. IV-VI. —Anjico bravo; monjoleiro. Map 14.

Discussion

This is a handsome tree of rapid growth, with ample panicles of white, honey-scented flowers. In the protologue it was distinguished from distantly vicariant but morphologically similar M. schomburgkii, grown side by side with it over a period of twelve years under cerrado conditions at Brasilia, principally by features of petiole- and wood-anatomy, but the longer corollas and longer basal auricle of the leaflets are more readily accessible differential characters. Kuhlmann (s.n., RB) noted that the bruised foliage of M. schomburgkii cultivated at Rio de Janeiro was resinously scented, a fact noted also by Ducke (1222, NY) at Manaus, whereas that of M. artemisiana was scentless. In material studied I could not find any pentamerous flowers as indicated in the protologue of M. artemisiana; I think they must occur only sporadically in this species, as they do in M. schomburgkii. The epithet artemisiana commemorates Dra. Maria Artemísia Arraes Hermans.

Distribution

Brazil South America| Rio de Janeiro Brazil South America| Bahia Brazil South America|