Mimosa coniflora Burkart

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 coniflora Burkart

Type

443. Mimosa coniflora Burkart in Reitz, Fl. ilus- tr. catarin. LEGU(l): 226, est. 36 + map. 1979. —"[Brazil] Santa Catarina: Garuva: Morro do Campo Alegre ... 1200 m . . . Reitz & Klein 10.994 (24.03.1961)."—Holotypus, SI (not seen); isotypi, NY! US!—Para

Description

Species Description - Slender erect unarmed microphyllous shrubs attaining 2 m, with fuscous defoliate annotinous and older stems strictly branched upward, the densely leafy homotinous branchlets and the peduncles silky-tomentulose when young with fine ± entangled, flexuous gray flagelliform setae, the pinna-rachises dorsally strigose with straight, forwardly subappressed, remotely scaberulous setae, the subconcolorous imbricate, ventrally concave lfts either glabrous or minutely puberulent facially, a little paler around the margin and weakly setulose-ciliolate, the small oblong capitula solitary in 3-6 distal lf-axils, in fruit persistent on defoliate trunks. Stipules erect papery castaneous ovate 1.5-4 x 1.1-1.8 mm, finely multistriate and minutely puberulent dorsally, weakly ciliolate, becoming dry but tardily deciduous. Leaf-stalks reduced to the small pulvinus, the one pair of pinnae seemingly sessile within the stipules; pinnae narrowly ascending, mostly 1.5-2.5 (ex char. -4) cm, the interfoliolar segments 0.4-0.7 mm; lfts (17-)20-28(-30)-jug., subequilong, the first pair close to minute setiform paraphyllidia, the blades obovate- or oblong-elliptic obtuse from shallowly semicordate base, the larger ones 2-2.7(-3.2) x 0.7-1.4(-1.8) mm, all imperceptibly venulose when young, finally 3-nerved when old and shrivelled. Peduncles 5-12 mm; capitula without filaments 7-10 x 3.5-4 mm, permanently conelike, the imbricate floral bracts in praefloration as long as or a little longer than the obtuse, apically puberulent fl-buds; bracts resembling stipules in texture, color and venulation, broadly triangular-ovate subacute 1-1.8 x 1-2 mm, glabrous dorsally, weakly arachnoid-ciliolate, persistent; flowers 4-merous, many lower ones staminate and some of these 8-androus, the distal ones bisexual 4-androus; calyx a minute membranous cup 0.2-0.25 mm, the rim truncate or obscurely denticulate; corolla of staminate fls turbinate ±1.8 mm, with shallowly concave 1 -nerved, scarcely thickened lobes ±0.8 x 0.8 mm, that of bisexual fls a little longer and narrower, the lobes ±0.7 x 0.6 mm; filaments pink, free to base, exserted 5.5-7 mm. Pods 1-2 from near top of receptacle, sessile, in profile oblong-elliptic ± 17-20 x 7-8 mm, 2-4- seeded, the replum ±1.2 mm wide, not indented between seeds, mucronulate at apex, densely setose with slender, narrowly ascending flagelliform setae to ±2.5 mm, the firmly papery valves comose with similar but less appressed setae, when ripe breaking up into free-falling indehiscent articles 4.5-5 mm long; seeds not seen.

Distribution and Ecology - On ledges and in crevices of granitic or gneissic rocks along banks of rapid streams at 900-1200 m, local near the crest of Sa. do Mar in municipios Garuva and Campo Alegre in n.-e. Sta. Catarina, Brazil; to be sought in adj. Paraná.— Fl. II-III.

Discussion

Mimosa coniflora resembles distantly allopatric M. microcarpa in broad multistriate stipules and floral bracts, but differs in minute, not paleaceous-pappiform calyx, in one-nerved, not striate corolla-lobes, and in craspedial, not valvate dehiscence of the pod. Mimosa congestifolia, its near neighbor on Sa. do Mar, is likewise similar in striate stipules and has a similar craspedium, but its leaflets (to 4.5-9, not 2-3 mm) and peduncles (15-35, not 5-12 mm) are much longer, its calyx is much deeper (0.7-0.9, not 0.20.25 mm), and its corollas much longer (3-3.8, not 1.8-2 mm). The dimorphic flowers of M. coniflora, as described above (observed in two capitula only), take the form described by Robinson (1898) under so-called subgenus Astatandra.

Distribution

Brazil South America| Santa Catarina Brazil South America|