This species is characterized by its medium-sized elliptic to elliptic-oblong leaves with slender tips, somewhat short tubular stipules with two well developed aristas, terminal, usually pedunculate, cymose inflorescences with flowers borne on short to well developed pedicels, short dentate calyx limbs, medium-sized pale to clear sky blue corollas with tubes ca. 6-16 mm long and lobes 3-10 mm long, and blue to black, markedly oblate fruits 5-8 x 8-16 that are also laterally strongly flattened. The leaves have developed undulate submarginal veins, and are thin-textured. The stipules are variously persistent with the leaves to deciduous or sometimes quickly caducous. The inflorescences are rounded in outline, and have reduced to developed bracts. Occasionally the bracts at the top of the peduncle are stipuiform or foliaceous, which produces the inflorescence arrangement Standley referred to as "sessile and tripartite" (that is, with the inflorescence composed of three apparent peduncles, the primary and two secondary, and subtended by leaves that are smaller than average). The calyx limbs range from subtruncate and ca. 0.1 mm long to dentate and ca. 1.2 mm long. The corolla tubes are cylindrical to funnelform, and longer than the lobes; the lobes are flat to somewhat thickened. The fruits are smooth or sometimes have 4 or 8 longitudinal ridges. The specimens dry variously clear green to brownish green or grayish green. This is one of the most widespread and commonly collected Faramea species, and often considered representative of the genus although its tubular stipules and distinctive fruit shape are found in perhaps half or fewer of its species.
As circumscribed here Faramea multiflora includes plants with a range of morphological variation. Steyermark (1967) studied plants from northeastern and Amazonian South America, and recognized a number of varieties. This species is here reviewed broadly and across its range, and circumscribed differently: several of Steyermark's varieties are treated as separate species, and no infraspecific taxa are recognized here (Taylor & Jardim, 2020). This treatment is, like Steyermark's provisional and this species still needs detailed regional study including field observations. The variation and apparent dynamics within Faramea multiflora are discussed in more detail here by geographic region, because the plants have been treated by different authors in different region and presumably have partially different biogeographic and evolutionary dynamics in these different regions. No regional groups of plants can be separated morphologically, though, so these regions are not separated here taxonomically.
Steyermark (1967) separated his 6 varieties based mainly on corolla overall length, inflorescence and degree of development of the inflorescences, and leaf size and details of the visible venation, and he separated similar plants with relatively narrow leaves and few-flowered inflorescences with slender axes into Faramea angustifolia. He did mention a few differences in corolla form, in particular the flowers of his var. amazonica having the lobes about as long as the tube, but he did not separate even this variety based on the corolla form and did not mention it for his other varieties (and the type of his var. maynensis has the same form). Steyermark did unfortunately separate some varieties based on size and position of the anthers within the corolla, apparently without realizing that the flowers of Faramea are distylous so these differences correspond to long-styled and short-styled flowers rather than species-level differences. His var. amazonica is distinctive in its corollas with the much lobes longer than in Faramea multiflora and longer than the tubes, and this flower form is here considered a species-level feature so those plants are separated as Faramea glandulosa.
Plants from the French Guiana, the type region of Faramea multiflora, have rather small to medium-sized, elliptic to lanceolate leaves, corymbiform-rounded lax inflorescences with several dozen flowers on developed pedicels, truncate to undulate calyx limbs 0.3-0.5 mm long, and blue corollas with cylindrical to funnelform tubes 6-8 mm long and somewhat fleshy lobes 3-5 mm long. Many specimens from this region have foliaceous bracts subtending the basalmost inflorescence axes, but these vary in development. Plants from the other Guianas and Pará in adjacent Brazil are similar in these features, as are most plants from eastern and southern Venezuela. Venezuelan plants show a wider range of leaf and inflorescence size, with inflorescences ranging to both smaller and larger. Plants from Caribbean northwestern Venezuela through northern Colombia are also similar to these Amazonian plants, or some Colombian plants have larger corollas similarly to some plants from western Colombia.
Steyermark's var. epedunculata corresponds to the plants with the lowermost inflorescence bracts foliaceous, which gives the inflorescence a sessile or "tripartite" form; the development of the bracts and this detail of the inflorescence arrangement varies frequently within this species, as seen within just the plants from one region in Central America, and within other species of various Rubiaceae genera so this feature is not here considered to distinguish a separate lineage. This inflorescence from is found occasionally across the northern part of the range of this species, from Amazonian Venezuela through Central America, and is common but not the only form found on the Caribbean drainage of South America. The plants of Caribbean South America, in northern Venezuela and Colombia, are included here within Faramea multiflora so this variety is not separated here. Steyermark included various specimens from sporadic localities across the Guianas, Venezuela, and Brazil also in this variety, but those have no other difference from Faramea multiflora and are here considered to show the variation in inflorescence bract development within this species. In any case Steyermark's circumscription of this variety is problematic, because one of the specimens he annotated as var. epedunculata is a collection made by L.C. Richard in French Guiana that appears to be the type of Faramea multiflora.
Some plants from eastern Bolivia, western Brazil (Mato Grosso), and southeastern Peru are distinctive in their relatively smaller narrower leaves, quite short petioles, corollas with cylindrical tubes on the smaller end of the size range for this species, and somewhat small fruits. These are often collected in gallery forest and somewhat dry vegetation, but are not completely separate morphologically from the typical form of Faramea multiflora, which is the common form in this region. The name Faramea benensis was based on a specimen from northeastern Brazil, but that has somewhat larger leaves with developed petioles and somewhat larger corollas with funnelform tubes and broader lobes; this specimen in fact corresponds quite closely to the type of Faramea multiflora. Faramea multiflora is also found in scattered localities through eastern Peru, western Brazil, eastern Ecuador, and southern Colombia, but is not common in those last areas.
In Central America and Mexico the corollas vary in form and size, with the tubes cylindrical to funnelform and 6-16 mm long and the lobes narrowly triangular to lanceolate, flat to a little thickened, and 3-10 mm long. The plants of this region have two somewhat well marked forms, which have been separated as Faramea multiflora and Faramea glandulosa by Taylor (e.g., Lorence et al. 2012). Plants with persistent stipules, well developed pedicels, reduced bracts, smooth often relatively smaller fruits, and a clear green drying color match the types of Faramea multiflora, Faramea salicifolia, and Faramea talamanacarum, and were treated as Faramea multiflora by Taylor (e.g., Beach 1426, Opler 1946). Plants with caducous stipules, relatively short pedicels subtended by regularly developed bracts, smooth to ridged often larger fruits, and often a gray or brown drying color match the types of Faramea stenura and Faramea hondurae, and were treated by Taylor as Faramea glandulosa (e.g., Folsom 9405, Folsom 5304). Leaf size also varies notably in some areas (e.g., McPherson 11497, 11817), and occasional plants from western Panama have ridged and also verrucose fruits (e.g., Santamaría 7851). A number of plants from eastern Mexico, especially Veracruz, often have few-flowered, sparsely branched inflorescences with unusually well developed pedicels. Further study shows that these features vary continuously within local populations (e.g., the plants at the La Selva Field Station, cf. the specimens collected there, also R. Aguilar, pers. comm.) and the two forms, as far as they are separable, are completely sympatric. Therefore these are combined here.
Plants corresponding to Faramea multiflora from Atlantic forest vegetation in eastern Brazil generally have relatively short, few-flowered inflorescences and corollas on the smaller end of the size range for this species. But, as noted by Steyermark 91967: 394-395), these are not completely distinct in any feature from the variation found in this species in other regions. Steyermark separated these as a variety of Faramea multiflora, but the Flora do Brazil 2020 did not separate them taxonomically and are followed here. The name Faramea salicifolia is based on a specimen from Atlantic forest in Rio de Janeiro; this name was used by Standley in sched. for relatively smaller plants of Faramea multiflora throughout its range, but as noted by Steyermark most of those plants do not correspond biogeographically to the type. Kuntze further expanded the range of Faramea salicifolia by using this name basically for Faramea multiflora and in particular for plants from Costa Rica. He also named two forms based on inflorescence arrangement; these were not described adequately to determine their identity and no original material has been found.
Faramea multiflora is similar to and has been confused with various Faramea species in particular in South America. Faramea multiflora is similar to Faramea brachysiphon of northern Central America, which has shorter corollas with the lobes longer than the tubes. Faramea multiflora is similar to and sometimes confused also with Faramea miconioides of east-central Peru, which has smaller corollas, leaves with well developed submarginal veins, and usually shorter more congested inflorescences. Faramea multiflora is also similar to Faramea platyneura of central Amazonia, which has corollas with cylindrical tubes 8-10 mm long and lobes that are shorter, ovate, and flat with a thin texture along with a dark gray drying color. Faramea multiflora is also very similar to Faramea glandulosa, and Steyermark considered these to belong to one species but they are separated here; Faramea glandulosa has corollas with funnelform tubes generally similar in size to those of Faramea multiflora and ovate, thin-textured lobes that are about equal to or longer than the tube. Faramea multiflora is also similar to Faramea scandens, which comprises plants found in the eastern foothills of the Andes from Colombia to Bolivian and has smaller corollas. Faramea angustifolia differs from all these species in its relatively very narrow leaves, inflorescences with 5-6 fasciculate slender axes, slender long pedicels, and smaller corollas; it may be no more than a particularly slender plant of Faramea multiflora. The recently described species Faramea camposiana and Faramea neilliana also comprise plants that were previously included in Faramea multiflora (Taylor & Jardim, 2020). Fruiting specimens of all these species are very difficult to separate.