Sabicea includes twining vines or sometimes erect shrubs found in Africa, Madagascar, and the Neotropics, which are characterized by their generally ovate, well developed stipules; opposite to verticillate leaves; axillary or regularly pseudoaxillary, generally rather short inflorescences; bisexual, homostylous or distylous flowers; five-lobed calyx limb; salverform to funnelform, white to pink corollas with five valvate lobes; five-locular ovaries; and five-locular, baccate, generally red to purple or black fruits with numerous small seeds. A number of species have white arachnoid to floccose pubescence and some, including several in Madagascar, have leaves in somewhat to markedly unequally sized pairs. The arrangement of the inflorescences, whether pseudoaxillary (i.e., developed in only one axil at a node) or axillary (in both axils) seems to vary in some species, but this character has not been studied in detail or comprehensively in the genus.
In Madagascar Sabicea has its center of diversity in the north and is characterized by pectinate stipules and sessile glomerulate or capitate inflorescences, except Sabicea marojejyensis has well developed peduncles. These peduncle initially are short but then elongate markedly, to several times their initial length when the flowers first open; in many Sabicea plants in Madagascar the calyx lobes also elongate markedly as the fruits develop, which is problematic because Wernham distinguished several species based on calyx lobe length, without specifying the flowering or fruiting stage. The species of Sabicea in Madagascar also generally have leaves that are oblique at the base. Sabicea diversifolia is the most widespread and commonly collected species. Wernham separated some of the Madagascar species by their calyx lobe form, "acicular" vs. "flattened"; however the calyx lobes are very narrowly triangular and flattened or laminar in all of these, apparently the calyx lobes he considered acicular are the particularly narrow ones. Sabicea has apparently not been studied in Madagscar since Wernham's world monograph of this genus, which is now a bit out of date, and with more material available now it appears that the separation and circumscripiton of several of the Sabicea species he recognized is problematic. For example, the specimen Malcomber et al. 1085 has been identified with three different names by different taxonomists at different times. This particular specimen is one of the two Madagascar Sabiceas included in the molecular analysis of Khan et al. (2008), which found them to be most closely related to each other.
Sabicea verticillata probably actually belongs to Danais, even though it was excluded from that genus by Puff & Buchner (1994); see additional comments on the species page.