Monographs Details: Mimosa sanguinolenta 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
Synonyms:Mimosa cruenta Benth.
Description:Species Description - Unarmed microphyllidious small shrubs and subshrubs from xylopodium, (4-)5-14 dm tall, with either erect or diffuse-assurgent, distally branched stems, finely villosulous throughout with erect or forwardly curved hairs 0.1-0.35 mm, eglandular, the epidermis of stems exfoliating in second year and the defoliate trunks smooth, the whole plant when dry dark brown or livid, the thick-textured plane lfts concolorous, sometimes glabrate on upper face, nowhere setose, the subglobose capitula single or rarely geminate in a long series of lf-axils on peduncle longer than subtending lf. Stipules erect ovate- or broadly lance-acuminate (1-) 1.5-3.5 x (0.6-)0.8-1.5 mm, bluntly 1-nerved dorsally, persistent. Leaf-stalks including small livid pulvinus 1-11 mm, low-convex dorsally, narrowly winged laterally, the petiole 1—2.5(—3) x 0.4-0.6 mm, the interpinnal segments l-3(-4) mm; pinnae commonly either 2-3- or 1-2-jug., rarely mostly 1- or all 3-4-jug., when more than 1-jug. a little accrescent upward, the rachis of distal (or only) pair 5-18 mm terminating in a lanceolate appendage, the interfoliolar segments 0.3-1 mm; lfts (4-)5-9(-10)-jug., accrescent distally, the first pair 0.6-1.2 mm distant from obliquely obovate or transversely dilated (sometimes unequal) paraphyllidia 0.5-0.9 x 0.6-1 mm, the blades oblong or oblong-obovate from deeply semicordate base, the distal ones (2.1-)2.5—4.5(-5.2) x 0.8-2(-2.2) mm, 2.3-3 times as long as wide, all veinless above, beneath (3-)4-nerved from pulvinule, the slightly displaced midrib 1-branched on each side distally, the inner posterior and (in broader lfts) one anterior primary nerve expiring beyond mid-blade, the rest very short, the venation coarse and bluntly prominulous. Peduncles 14-29 mm; capitula without filaments 6-8 mm diam., prior to anthesis moriform, the obtuse fl-buds thinly gray-hispidulous and rarely in addition with a few claviform, perhaps glandular trichomes; bracts linear, attenuate at each end, 1.2-2 x 0.2-0.3 mm, puberulent and ciliolate, persistent; flowers 4(-5)-merous diplostemonous, all or almost all bisexual; calyx membranous, shallowly campanulate 0.5-0.9 mm, either puberulent or glabrous externally, the low-deltate teeth 0.1-0.2 mm, minutely ciliolate; corolla turbinate 2.5-3.4 mm, the ovate 1-nerved, apically cucullate but not thickened lobes 1.1-1.5 x 0.7-1 mm; filaments pink, united at base into a stemonozone to 0.4 mm, the longer set exserted 5.5-6.5 mm. Pods commonly 3-15 per capitulum, spreading and ascending in loose umbellate cluster, sessile or cuneately pseudostipitate, in profile varying from oblong-elliptic to linear-oblong (7-) 10-23 x 5-6 mm, (l-)2-6(-8)-seeded, the straight or shallowly constricted replum 0.7-1.2 mm diam., short-cuspidate at apex, persistent entire after dehiscence of valves, the stiffly papery nigrescent valves low-colliculate over each seed, when ripe separating entire from replum and from each other except at very base, basipetally dehiscent and gaping to release the seeds, the replum and valves alike finely minutely puberulent eglandular; seeds (few seen) obliquely descending ±4.5 x 3 mm, the testa fuscous.

Distribution and Ecology - In campo, in Paraná attaining 800-1000 m but lower w.- and s.-ward, scattered from n.-e. Argentina (Entre Ríos to Misiones) e. to upland and Atlantic s.-e. Brazil and Uruguay, in Brazil extending rarely n. through centr. Sta. Catarina to the Iguaçú valley in w. Paraná (mun. Marmoleiro and Larangeiras do Sul).—Fl. XI-II(-?).

Discussion:

While accepting without reservation Burkart’s analysis of the original M. cruenta Bentham into two species, one (M. amphigena Burkart) with armed stems and craspedia, the other (M. cruenta sensu Burkart) with unarmed stems and valvately dehiscent pods, I cannot endorse his typification of M. cruenta by Sello 3085 at C, illustrated by Field Museum Negative 21876. It is not disputed that Bentham derived the protologue of M. cruenta from elements of two taxa. In Flora brasiliensis (1876, l.c.) Bentham admitted as much: "Specimina typica Tweedieana omnia aculeata sunt, Selloana aculeata et inermia. Specimina pauca inermia pinnis 4-5-jugis varietatem vel forte speciem distinctam indicant." This forthright statement unequivocally lectotypifies M. cruenta by the aculeate plants collected in Uruguay valley by Tweedie, whose field-note on color of the flowers suggested the epithet. These plants represent in my opinion nothing other than M. amphigena Burkart, which consequently must fall into synonymy. Sello’s unarmed plant that was mentioned by Bentham as found among specimens of M. cruenta has apparently never received a valid name, though it has been described in meticulous detail and well illustrated by Burkart (1948, 1979, 1987, ll.cc.) under the name M. cruenta. The specimen chosen as typus of M. sanguinolenta is among those identified by Burkart as M. cruenta.

I have seen no material corresponding with the plant described by Burkart as: M. cruenta var. glabra Burkart, Darwiniana 7: 522. 1947.—". . . Brasil. Rio Grande do Sul, Morro da Gloria cerca de Porto Alegre, en campo, B. Rambo 30598, 18.IX.1945 "-Holotypus, SI; paratypi, Rambo 175, 26928, 27309, all SI.

According to the protologue this appears to be a completely glabrate state of M. sanguinolenta, unarmed and with valvately dehiscent pods of the species.

Distribution:Uruguay South America| Brazil South America| Paraná Brazil South America| Santa Catarina Brazil South America| Argentina South America| Entre Ríos Argentina South America| Misiones Argentina South America|