Monographs Details: Strychnos glabra Sagot ex Progel
Authority: Krukoff, Boris A. 1965. Supplementary notes on the American species of Strychnos VII. Mem. New York Bot. Gard. 12: 1-94.
Family:Loganiaceae
Description:Distribution and Ecology - British Guiana: Schomburgk 957 (W), Forest Dept. 2467 (K). Brazil: Para (Rio Mojú), Froes 33940; Amazonas: basin of Rio Negro (near Manaos), Ducke 1925. (US).Distribution: British Guiana (Essequibo and Berbice); French Guiana and Amazonian Brazil (in the State of Para it was collected on the upper Pam, in the basin of Rio Guama and near Catú; in the State of Amazonas, in the basins of the lower and upper Rio Negro and of Rio Solimoes; in the Territory of Rio Branco). Doubtless occurs also in Surinam, in Peru and Colombia.

Discussion:In our monograph in 1942 we placed this species with reservations in the synonymy under S. guianensis and we reinstated it as a valid species in 1948, once the type coll. (Sagot 829) and good flowering and fruiting material of it (Ducke s.n., Sept. 21, 1945) become available to us. At the same time we placed S. Crevauxiana in the synonymy under S. glabra, this after examination of the type of S. Crevauxiana (Crevaux s.n., June 1879). In his paper (31: 33) Ducke states: “A esta especie, Krukoff atribue, como sinônimo, S. Crevauxiana Baill., uma das classicas plantas de curare. Foi coletada em estado florifero por Crevaux, no alto Rio Parú (Brazil, Estado do Pará e não Guiana francesa!) onde fornecia o veneno dos Indios Urucurianas (“Roucouyen-nes” na Guiana francesa). Fróes encontrou uma planta estéril, atribuida por Krukoff a S. glabra e muito parecida com o desenho da de Crevaux (Rio Negro, fóz do Içana, Froes 21528, “unica usada pelos indios Baniuas, para o veneno irari”) ; no entanto, na casca da S. glabra de Belem a Manaos não se observou atividade curarisante. Bovet e Marini-Bettolo encontraram n’ela um alcaloide de ação central paralisante. Mais material para estudias botânicos e quimicos sera necessario para resolver definitimente a questão da identidade da S. Crevauxiana!" Let us consider carefully Ducke’s suggestion and let us see as to whether or not the paralyzing activity of the extract of bark should enter into consideration in resolving the identity of S. Crevauxiana. First let us quote as to what Ducke himself states on the paralyzing activity of the closely related S. guianensis (31: 33): “estudos quimicos, realizados em varias instituiçoes têm dado resultado muito variável quanto à atividade curarisante, fraquissima n’alguns casos, pelo que parece provável que somente certas raças d’esta polimorfa espécie forneçam veneno de flexas.” In another place in the same paper (31: 8) Ducke states: A espécie S. guianensis (no sentido da monografia de Krukoff) varia não só naqueles caracteres mas ainda, na toxidez das amostras estudadas, forte em algumas, em outras quasi nula; não há no entanto dúvida que esta especie fornece curare a várias tribus de indios. Ignoramos se existe algum parlelismo entre a toxidez, e as caracteres morfológicos das diversas formas da espécie.” The variability in the paralyzing activity in the polymorphic and variable S. guianensis has been suspected and proof of this was obtained on actual experiments with this plant conducted at Merck Research Laboratories in the late thirties. However, this matter of the variability in the paralyzing activity is complicated by the parts of plants from which samples are collected (root bark or stem bark from the lower part of the stem or stem bark from the upper part of the stem), the age of plants, the season of collection, the method of preparation of samples, as well as by the age of samples on which assays are made. Still in another place in the same paper (31: 16) Ducke also states: “Nenhuma relação existe entre as affinidades das espécies segundo os seus caracteres morfológicos, e a sua atividade curarisante.” If Ducke would be consistent then he also should have questioned our disposition of S. Curare H.B.K., the classical curare plant of the Indians at Esmeralda on the upper Rio Orinoco in Venezuela as reported by Humboldt and Bonpland (1: 299), and which is undoubtedly S. guianensis. Ducke is probably correct in that the type collection of S. Crevauxiana was collected on the upper Parú, State of Para, Brazil, and not on the upper Parú, southern French Guiana, as we stated in our monograph (1: 298-299). On a new map of eastern South America (Atlas Plate 27; Sept. 1962; compiled and drawn in the Carthographic Division of the National Geographic Society) Rio Pam is clearly shown as being confined to Brazil. In order to verify the status of S. Crevauxiana, Ducke should have examined the type collections of S. glabra and S. Crevauxiana. If these in his opinion were not sufficient for settling this question, then new collections are needed from the type locality of S. glabra (Karouany, French Guiana) and the type locality of S. Crevauxiana (basin of the upper Parú, Para, Brazil). Froes 21258 from Fóz do Içana, Rio Negro, as well as the collections near Belem and Manaos, to which Ducke refers, are of little consequence for verifying the disposition of S. Crevauxiana. It is most unlikely that it could be reinstated as a good species, in spite of all temptations, as it is one of the historical curare plants. For information on the position of S. glabra in Ducke’s key made on the basis of fruit characters, see under S. rondeletioides. The type of S. Crevauxiana was reported by Crevaux as the main ingredient of curare of the Trios and of the Roucouyennes. Froes states on the label (Froes 21528 from Rio Içana, basin of the upper Rio Negro, Amazonas, Brazil): “unico usado pelos Indios Baniuas para o veneno Trary’.” Fanshawe (34: 67) gives the following information on the local names, on its distribution in British Guiana and on its alkaloids, probably on the authority oí Dr. King: “Local names: Devildoer; kwabanaro (Arawak); kumarawa (Akawaio, Are-kuna, Patamona, Macushi). “A canopy climber. It occurs rarely in wallaba forest on white sandy soil in the Eastern district. “It contains at least two alkaloids, one of which has a strong curare-like action, i.e. causing paralysis of the peripheral nerves.” As per King, the alkaloid content of this species was found to be “ + +,” curare action, “active” (75). This work was done on For. Dept. 2620 (from British Guiana) which we cite under S. glabra (4: 345). In the same paper King also reports tests (the alkaloid content, “0”, curare action, “none”) for For. Dept. 2467 referred to by him as “near S. guianensis” and which is cited as S. glabra in this paper. It is not known what part of the plants was used for this work, presumably stem bark. This species was studied by Marini-Bettolo, Bovet and their coworkers. For the alkaloid content, toxicity and curare activity of the total extracts, see (94: 856; 95: 1142, 1144). In another paper the same authors state: “alcaloides dotés d’une action sur le système nerveux central; activité curarisante, ‘0’ ” (108: 269). The above referred to work was done on stem bark collected by Ducke, one collection on Estrada Aleixo, Manaos, Amazonas, Brazil in April 1953, and another collection near Belem. Para, Brazil in April 1952 (95:1145; 108:269).
Distribution:Guyana South America| Brazil South America| Suriname South America| Peru South America| Colombia South America|