Monographs Details:
Authority:
Mori, S. A. 1987. The Lecythidaceae of a lowland Neotropical Forest: La Fumée mountain, French Guiana. Mem. New York Bot. Gard. 44: 1-190.
Mori, S. A. 1987. The Lecythidaceae of a lowland Neotropical Forest: La Fumée mountain, French Guiana. Mem. New York Bot. Gard. 44: 1-190.
Family:
Menispermaceae
Menispermaceae
Description:
Genus Description - Vines, usually of modest size, flowering when herbaceous or only softly woody, the ropelike trunks (in some) clothed in age with furrowed, corky bark, the young branches canaliculate, not or obscurely lenticellate, the foliage varying from glabrous to densely setose-pilose; petioles thickened and twisted at base; leaf-blades of 5 main types: a) laurel-like, i.e. ovate from a rounded or truncate base, with primarily pinnate venation; b) ipomoea-like, i.e. cordate to hastate or suborbicular with descending basal lobes and a primarily palmate venation; c) peltate, a variation of the last in which the descending basal lobes of the blade become fused; d) palmatilobate, a variation of type b) with primarily radiate venation; and e) palmately 3-5-foliolate, the divisions of the blade contracted into a naked costa and appearing petiolulate; leaf-types uniform through all individuals of (so far as known) most species but in one (D. ernstii) pleomorphic, of type b) in fertile branches, of type d) or varying thereto in sterile shoots, the blades then becoming (often) whitish-maculate; inflorescences arising either singly from (or from just above) axils of contemporary leaves or subcorymbosely from leafless short-shoots issuing either from the same points as simple inflorescences or (rarely ) directly from the leafless trunk, of both sexes usually simple, spicate, the sessile, solitary flowers subtended by a small, deflexed bract and the axis of the [female] inflorescence ±thickened under each flower, but in sect. Meximenium the [male] flowers pedicelled and the drupe elevated on a laterally flattened, vanelike pedicel, in sect. Sicyopsis the inflorescences of both sexes composite, the flowers pedicelled and borne on short secondary branchlets accompanied by elongate bracts; flower [male]: sepals 6, rotate or erect-connivent, often but not always carnose, united only at base or (sect. Taubertia, Sphinctonema) through half their length into a cup; petals usually 6, either ± carnose, adnate at base to the sepals and crowded together to form a pseudodisc, their juxtaposed margins then either fused (sect. Disciphania) or free (sect. Sarcostephana), or erect and separated, then variable in form, commonly membranous, or scale-like, sometimes reduced to 3, or (sect. Sphinctonema) obsolete; androecium 3-merous, the stamens free from the base, the filament often greatly dilated upward and passing into a broad connective, rarely linear, or constricted at the middle, or reduced to the connective; anther-sacs either lateral or (with broad connective) lateral at base and introrse distally, opening by vertical or oblique slits; flower [female]: sepals and petals as in but often smaller; staminodes 0; drupe grapelike, oblong-ellipsoid, a little obcompressed, with a leathery, at first green, finally (at least in some) red exocarp and thin, mucilaginous, hardly fibrous pulp; endocarp cartilaginous or crustaceous, with ovoid-ellipsoid, dorsoventrally compressed body prominently 8-ribbed lengthwise (ribs 2 marginal, 1 dorsal, 1 ventral, 4 interposed toward the margins), the ribs in section deltate or (often) expanded into broad wings traversed by stiff radiating, spokelike fibers, these connected by a membrane or sometimes dissolved into a coarse fringe; seed-cavity oblong-ellipsoid, symmetrical or slightly incurved but not moulded over or around a condyle, the dorsal and ventral faces in consequence essentially alike; embryo and albumen of Tinosporeae.
Genus Description - Vines, usually of modest size, flowering when herbaceous or only softly woody, the ropelike trunks (in some) clothed in age with furrowed, corky bark, the young branches canaliculate, not or obscurely lenticellate, the foliage varying from glabrous to densely setose-pilose; petioles thickened and twisted at base; leaf-blades of 5 main types: a) laurel-like, i.e. ovate from a rounded or truncate base, with primarily pinnate venation; b) ipomoea-like, i.e. cordate to hastate or suborbicular with descending basal lobes and a primarily palmate venation; c) peltate, a variation of the last in which the descending basal lobes of the blade become fused; d) palmatilobate, a variation of type b) with primarily radiate venation; and e) palmately 3-5-foliolate, the divisions of the blade contracted into a naked costa and appearing petiolulate; leaf-types uniform through all individuals of (so far as known) most species but in one (D. ernstii) pleomorphic, of type b) in fertile branches, of type d) or varying thereto in sterile shoots, the blades then becoming (often) whitish-maculate; inflorescences arising either singly from (or from just above) axils of contemporary leaves or subcorymbosely from leafless short-shoots issuing either from the same points as simple inflorescences or (rarely ) directly from the leafless trunk, of both sexes usually simple, spicate, the sessile, solitary flowers subtended by a small, deflexed bract and the axis of the [female] inflorescence ±thickened under each flower, but in sect. Meximenium the [male] flowers pedicelled and the drupe elevated on a laterally flattened, vanelike pedicel, in sect. Sicyopsis the inflorescences of both sexes composite, the flowers pedicelled and borne on short secondary branchlets accompanied by elongate bracts; flower [male]: sepals 6, rotate or erect-connivent, often but not always carnose, united only at base or (sect. Taubertia, Sphinctonema) through half their length into a cup; petals usually 6, either ± carnose, adnate at base to the sepals and crowded together to form a pseudodisc, their juxtaposed margins then either fused (sect. Disciphania) or free (sect. Sarcostephana), or erect and separated, then variable in form, commonly membranous, or scale-like, sometimes reduced to 3, or (sect. Sphinctonema) obsolete; androecium 3-merous, the stamens free from the base, the filament often greatly dilated upward and passing into a broad connective, rarely linear, or constricted at the middle, or reduced to the connective; anther-sacs either lateral or (with broad connective) lateral at base and introrse distally, opening by vertical or oblique slits; flower [female]: sepals and petals as in but often smaller; staminodes 0; drupe grapelike, oblong-ellipsoid, a little obcompressed, with a leathery, at first green, finally (at least in some) red exocarp and thin, mucilaginous, hardly fibrous pulp; endocarp cartilaginous or crustaceous, with ovoid-ellipsoid, dorsoventrally compressed body prominently 8-ribbed lengthwise (ribs 2 marginal, 1 dorsal, 1 ventral, 4 interposed toward the margins), the ribs in section deltate or (often) expanded into broad wings traversed by stiff radiating, spokelike fibers, these connected by a membrane or sometimes dissolved into a coarse fringe; seed-cavity oblong-ellipsoid, symmetrical or slightly incurved but not moulded over or around a condyle, the dorsal and ventral faces in consequence essentially alike; embryo and albumen of Tinosporeae.
Discussion:
Type. Disciphania lobata Eichler, Jahrb. Bot. Gart. Berlin 2: 328. 1883; Diels in Pflanzenriech IV. 94: 174-179, Fig. 63. 1910. Species ±25 or more, of which 20 are here described in some detail, several known only from specimens of one sex or from only one collection, widely dispersed through tropical America between lat. 22° N. and 26° S., most abundant in the upper Amazonian Hylaea and along the eastern piedmont of the Andes, extending to the Pacific slope in Ecuador, N to the Caribbean coast of Veneuela and (becoming rare, scattered, and locally endemic) through Central America to southern Mexico, S through interior Bolivia and adjoining Brazil to Paraguay and (again with several local endemics) into southeastern Brazil; one isolated on Hispaniola. Apparently absent from lower Amazonian Brazil, from the Guianas, and the Guyana Highland. Habitats various, but mostly of second-growth forest, or along rivers, avoiding high-canopy forest; pronounced mesophytes. Drupes sometimes sweet and edible. The genus Disciphania was described to accommodate the staminate plant of D. lobata, a species which appears today peripheral to the genus that has grown up around its nucleus. As implied by the name, the feature of D. lobata that seemed at the time generically diagnostic lay in the staminate perianth. This consists of six fleshy sepals united at base only and at full anthesis rotately spreading; within the sepals and except for a narrow free margin adnate to them stands a thinly carnose disc contrived out of six broadly wedgeshaped petals united by their margins. At the center of this disc a small round cavity is occupied by three subsessile stamens which consist of a broadly rhombic connective bearing along the distal edges and across the inner face a pair of relatively large vertically dehiscent anther-sacs. This flower, of a dull red color that turns brown or blackish when dried, is associated with a remarkable pubescence of extremely long, lustrous, setiform hairs, retrorse on the young stems and petioles but spreading from the veins of the large, basally cordate leaves which are variably angulate or deeply three-lobed beyond the middle. Altogether D. lobata is a remarkable monotype. The drupe, not known to Eichler, has a hispid exocarp and a straight, dorsoventrally compressed, 8-carinate (but not winged) endocarp. The species next described, D. ernstii, has since proved to represent a substantial group of wide dispersal through tropical South America, here called sect. Sarcostephana. Its members differ collectively from D. lobata in having within the staminate flower a disc of petals greatly thickened and carnose but less strongly adnate to the anteposed sepals and made up of sex separate even though closely juxtaposed parts. The exocarp of the drupe is glabrous, and the eight keels of the otherwise similar endocarp are all developed into wide thin wings yielding a linear section. (The endocarp suggests a large fruit of a peucedanoid umbellifer, e.g. Pteryxia, in consequence.) The leaf-blade of sect. Sarcostephana varies in outline from the ipomoea-type to the laurel-type, and in all but one species is uniform throughout plants of either sex. In D. ernstii, however, the blade of leaves directly associated with an inflorescence, whether staminate or pistillate, is of the ipomoea-type, but gives way, on sterile branches, to leaver astonishingly variable in outline, changing along the stem from pentagonal to deeply palmatilobate. Such leaves are in addition often curiously whitish-maeulate and, detached from the fertile plant, seem to belong to a plant of a different genus. Although it has been suspected that some degree of foliar pleomorphy may occur throughout Disciphania, there is no evidence that this is the case outside of D. ernstii (sens, lat.) and, to the extent described above (but there associated with the inflorescence) D. lobata. More observation in the field is required before we can be sure of the facts. The remaining species of Disciphania, accounting for about half the genus as now known, have flowers of at least superficially different sort. In sect. Taubertia, originally described as a distinct genus and with some claim to be so considered, the staminate flower is much smaller than that of any member of sect. Sarcostephana and different in structure also. The sepals are united through half their length into a little fleshy cup, beyond which the free blades spread stellately in early anthesis, becoming reflexed in age. There are still six petals, but these are erect, not fleshy-thickened, and stand separate from one another; they do not form in any sense a disclike crown such as was thought at first to be characteristic of Disciphania. The fruit of the original Taubertia (D. peltata) is still unknown, but that of the related D. modesta is similar to the fruit of sect. Sarcostephana except that the endocarp is only narrowly winged. The androecium associated with this type of perianth has well-developed, linear or clavately linear filaments and much less prominent connectives. Yet another type of staminate flower is found in sect. Dioscoreopsis. Here the sepals are small as in sect. Taubertia but free almost from the base and they remain permanently erect, often with slightly connivent tips. The accompanying petals are reduced to membranous scales, three of them sometimes obsolete. The filaments are short, linear or clavately dilated upward, but the anther-sacs are collateral or almost so. The fruit of only one (of three) species of sect. Dioscoreopsis is known; it is essentially as in sect. Sarcostephana. The species mentioned so far are South American. There remain four highly localized and strongly characterized Central American and Mexican Disciphaniae and a fifth from Hispaniola which do not fit comfortably into any group described up to this point. One Mexican species, D. cardiophylla, is known only from staminate material. The flower has nearly the sepals of sect. Taubertia but is apetalous; the androecium is unique. The stamens are shaped like an hour-glass, abruptly waisted between the broad connective and the dilated filament proper. Moreover the inner face of each sepal alternating with a stamen bears a conical protuberance that fits neatly into the gap formed by juxtaposition of the filaments’s “waists,” thereby closing the orifice of the flower at a level just below the anthers. I refer D. cardiophylla, which has leaves of the ipomoea-type, to a monotypic sect. Sphinctonema. The four North American species that remain have in common leaf-blades of the palmatipartite type associated with the inflorescences of both sexes and apparently uniform throughout the plant. Three of these, of Mexico and Costa Rica, form the sect. Meximenium. Their fruits resemble that of D. lobata (except for glabrous exocarp), the endocarp being crested but not winged; but the drupes when ripe are elevated on laterally flattened, vanelike pedicels. The staminate flower of sect. Meximenium is known only in D. nesiotes. It introduces to Disciphania the hitherto foreign feature of pedicellate flowers and converts the spike into a raceme. The outer whorls of the staminate perianth in D. nesiotes are much as in sect. Sarcostephana; on the other hand the petals are membranous and free, evoking sect. Taubertia with this difference, that they are marginally involute and embrace the linear filaments. The peculiar D. domingensis, apparently endemic to Hispaniola, closely resembles D. vesiotes in general habit, but the inflorescence of both sexes is composite, the flowers, pedicelled as in D. nesiotes, being borne two or three together on short branchlets of the second order. It seems possible that the branchlets, which are supported by elongate, linear-oblanceolate bracts unlike any seen elsewhere in Disciphania, are in reality greatly reduced whole inflorescences, and the apparent inflorescence a reduced and apocopated homology for the pseudocorymbose inflorescences described above. However this may be, the staminate flower of D. domingensis has sepals of a size and shape suggesting sect. Sarcostephana (but submembranous, and externally hispid); they are united at base into a shallow cup (evoking sect. Taubertia) but rotate distally. The small, mutually free petals are adnate to the sepals by a fleshy claw and then expanded into a minute, submembranous blade. The filaments are linear and intorsely geniculate at apex. The fruit is yet unknown. Without going into further detail it must be obvious that Disciphania, since it was last studied in detail by Diels (1910), has expanded to the point where a new generic definition is required, with emphasis on features not considered formerly to be of great importance. The genus now includes an unforeseen variety of leaf-types, of staminate perianths, of androecia, and even of entire inflorescences. Although the androecium remains constantly trimerous, and the filaments remain free from one another, the stem of the filament varies from broadly cuneiform (as considered typical for Disciphania by Diels) to linear, and its distal prolongation between the anther-sacs (the connective) from broadly deltate to almost obsolete. The petals may now be either fleshy or membranous, and vary greatly in shape and development of the blade. At the same time, but without exact correlation, the staminate perianth varies from rotate to campanulate, its parts variably coalescent into a tube. By contrast the drupe remains (so far as known) essentially constant in form and content, only that of D. lobata (the generitype) standing apart from the rest insofar that the exocarp is charged with hispid bristles. The endocarp is virtually monomorphic, differing only from one group of species to the next in the development of the keels and lateral angles from low crests into wide, submembranous wings. A scheme of classification that depended primarily on the staminate flower would permit recognition within what is here called Disciphania of six or seven small genera corresponding to the sections defined in this paper. Such genera would be obviously interrelated, much more closely so to each other than to any group of Menispermaceae with the possible exception of Aspidocarya Miers. It appears, however, that the menispermaceous flower, at least in tribe Tinosporeae, is highly plastic in its organization, and while it offers traits of capital diagnostic value at the level of species it is unsuited by its very plasticity to form the basis of a generic classification. On the other hand the fruit, within narrow limits, remains static, differing only superficially in ornamentation of the endo-carpic testa but hardly at all in essential form. In Disciphania, as in Odonotocarya, it is the endocarp that expresses the fundamental unity of the genus.
Type. Disciphania lobata Eichler, Jahrb. Bot. Gart. Berlin 2: 328. 1883; Diels in Pflanzenriech IV. 94: 174-179, Fig. 63. 1910. Species ±25 or more, of which 20 are here described in some detail, several known only from specimens of one sex or from only one collection, widely dispersed through tropical America between lat. 22° N. and 26° S., most abundant in the upper Amazonian Hylaea and along the eastern piedmont of the Andes, extending to the Pacific slope in Ecuador, N to the Caribbean coast of Veneuela and (becoming rare, scattered, and locally endemic) through Central America to southern Mexico, S through interior Bolivia and adjoining Brazil to Paraguay and (again with several local endemics) into southeastern Brazil; one isolated on Hispaniola. Apparently absent from lower Amazonian Brazil, from the Guianas, and the Guyana Highland. Habitats various, but mostly of second-growth forest, or along rivers, avoiding high-canopy forest; pronounced mesophytes. Drupes sometimes sweet and edible. The genus Disciphania was described to accommodate the staminate plant of D. lobata, a species which appears today peripheral to the genus that has grown up around its nucleus. As implied by the name, the feature of D. lobata that seemed at the time generically diagnostic lay in the staminate perianth. This consists of six fleshy sepals united at base only and at full anthesis rotately spreading; within the sepals and except for a narrow free margin adnate to them stands a thinly carnose disc contrived out of six broadly wedgeshaped petals united by their margins. At the center of this disc a small round cavity is occupied by three subsessile stamens which consist of a broadly rhombic connective bearing along the distal edges and across the inner face a pair of relatively large vertically dehiscent anther-sacs. This flower, of a dull red color that turns brown or blackish when dried, is associated with a remarkable pubescence of extremely long, lustrous, setiform hairs, retrorse on the young stems and petioles but spreading from the veins of the large, basally cordate leaves which are variably angulate or deeply three-lobed beyond the middle. Altogether D. lobata is a remarkable monotype. The drupe, not known to Eichler, has a hispid exocarp and a straight, dorsoventrally compressed, 8-carinate (but not winged) endocarp. The species next described, D. ernstii, has since proved to represent a substantial group of wide dispersal through tropical South America, here called sect. Sarcostephana. Its members differ collectively from D. lobata in having within the staminate flower a disc of petals greatly thickened and carnose but less strongly adnate to the anteposed sepals and made up of sex separate even though closely juxtaposed parts. The exocarp of the drupe is glabrous, and the eight keels of the otherwise similar endocarp are all developed into wide thin wings yielding a linear section. (The endocarp suggests a large fruit of a peucedanoid umbellifer, e.g. Pteryxia, in consequence.) The leaf-blade of sect. Sarcostephana varies in outline from the ipomoea-type to the laurel-type, and in all but one species is uniform throughout plants of either sex. In D. ernstii, however, the blade of leaves directly associated with an inflorescence, whether staminate or pistillate, is of the ipomoea-type, but gives way, on sterile branches, to leaver astonishingly variable in outline, changing along the stem from pentagonal to deeply palmatilobate. Such leaves are in addition often curiously whitish-maeulate and, detached from the fertile plant, seem to belong to a plant of a different genus. Although it has been suspected that some degree of foliar pleomorphy may occur throughout Disciphania, there is no evidence that this is the case outside of D. ernstii (sens, lat.) and, to the extent described above (but there associated with the inflorescence) D. lobata. More observation in the field is required before we can be sure of the facts. The remaining species of Disciphania, accounting for about half the genus as now known, have flowers of at least superficially different sort. In sect. Taubertia, originally described as a distinct genus and with some claim to be so considered, the staminate flower is much smaller than that of any member of sect. Sarcostephana and different in structure also. The sepals are united through half their length into a little fleshy cup, beyond which the free blades spread stellately in early anthesis, becoming reflexed in age. There are still six petals, but these are erect, not fleshy-thickened, and stand separate from one another; they do not form in any sense a disclike crown such as was thought at first to be characteristic of Disciphania. The fruit of the original Taubertia (D. peltata) is still unknown, but that of the related D. modesta is similar to the fruit of sect. Sarcostephana except that the endocarp is only narrowly winged. The androecium associated with this type of perianth has well-developed, linear or clavately linear filaments and much less prominent connectives. Yet another type of staminate flower is found in sect. Dioscoreopsis. Here the sepals are small as in sect. Taubertia but free almost from the base and they remain permanently erect, often with slightly connivent tips. The accompanying petals are reduced to membranous scales, three of them sometimes obsolete. The filaments are short, linear or clavately dilated upward, but the anther-sacs are collateral or almost so. The fruit of only one (of three) species of sect. Dioscoreopsis is known; it is essentially as in sect. Sarcostephana. The species mentioned so far are South American. There remain four highly localized and strongly characterized Central American and Mexican Disciphaniae and a fifth from Hispaniola which do not fit comfortably into any group described up to this point. One Mexican species, D. cardiophylla, is known only from staminate material. The flower has nearly the sepals of sect. Taubertia but is apetalous; the androecium is unique. The stamens are shaped like an hour-glass, abruptly waisted between the broad connective and the dilated filament proper. Moreover the inner face of each sepal alternating with a stamen bears a conical protuberance that fits neatly into the gap formed by juxtaposition of the filaments’s “waists,” thereby closing the orifice of the flower at a level just below the anthers. I refer D. cardiophylla, which has leaves of the ipomoea-type, to a monotypic sect. Sphinctonema. The four North American species that remain have in common leaf-blades of the palmatipartite type associated with the inflorescences of both sexes and apparently uniform throughout the plant. Three of these, of Mexico and Costa Rica, form the sect. Meximenium. Their fruits resemble that of D. lobata (except for glabrous exocarp), the endocarp being crested but not winged; but the drupes when ripe are elevated on laterally flattened, vanelike pedicels. The staminate flower of sect. Meximenium is known only in D. nesiotes. It introduces to Disciphania the hitherto foreign feature of pedicellate flowers and converts the spike into a raceme. The outer whorls of the staminate perianth in D. nesiotes are much as in sect. Sarcostephana; on the other hand the petals are membranous and free, evoking sect. Taubertia with this difference, that they are marginally involute and embrace the linear filaments. The peculiar D. domingensis, apparently endemic to Hispaniola, closely resembles D. vesiotes in general habit, but the inflorescence of both sexes is composite, the flowers, pedicelled as in D. nesiotes, being borne two or three together on short branchlets of the second order. It seems possible that the branchlets, which are supported by elongate, linear-oblanceolate bracts unlike any seen elsewhere in Disciphania, are in reality greatly reduced whole inflorescences, and the apparent inflorescence a reduced and apocopated homology for the pseudocorymbose inflorescences described above. However this may be, the staminate flower of D. domingensis has sepals of a size and shape suggesting sect. Sarcostephana (but submembranous, and externally hispid); they are united at base into a shallow cup (evoking sect. Taubertia) but rotate distally. The small, mutually free petals are adnate to the sepals by a fleshy claw and then expanded into a minute, submembranous blade. The filaments are linear and intorsely geniculate at apex. The fruit is yet unknown. Without going into further detail it must be obvious that Disciphania, since it was last studied in detail by Diels (1910), has expanded to the point where a new generic definition is required, with emphasis on features not considered formerly to be of great importance. The genus now includes an unforeseen variety of leaf-types, of staminate perianths, of androecia, and even of entire inflorescences. Although the androecium remains constantly trimerous, and the filaments remain free from one another, the stem of the filament varies from broadly cuneiform (as considered typical for Disciphania by Diels) to linear, and its distal prolongation between the anther-sacs (the connective) from broadly deltate to almost obsolete. The petals may now be either fleshy or membranous, and vary greatly in shape and development of the blade. At the same time, but without exact correlation, the staminate perianth varies from rotate to campanulate, its parts variably coalescent into a tube. By contrast the drupe remains (so far as known) essentially constant in form and content, only that of D. lobata (the generitype) standing apart from the rest insofar that the exocarp is charged with hispid bristles. The endocarp is virtually monomorphic, differing only from one group of species to the next in the development of the keels and lateral angles from low crests into wide, submembranous wings. A scheme of classification that depended primarily on the staminate flower would permit recognition within what is here called Disciphania of six or seven small genera corresponding to the sections defined in this paper. Such genera would be obviously interrelated, much more closely so to each other than to any group of Menispermaceae with the possible exception of Aspidocarya Miers. It appears, however, that the menispermaceous flower, at least in tribe Tinosporeae, is highly plastic in its organization, and while it offers traits of capital diagnostic value at the level of species it is unsuited by its very plasticity to form the basis of a generic classification. On the other hand the fruit, within narrow limits, remains static, differing only superficially in ornamentation of the endo-carpic testa but hardly at all in essential form. In Disciphania, as in Odonotocarya, it is the endocarp that expresses the fundamental unity of the genus.