We received this plant labeled as Cynanchum viminale, which it clearly is not. Through morphological observation and careful flower dissection, we’ve identified it as Karimbolea macrantha, a species only described in 1998 from Cape Sainte Marie in southern Madagascar. This monotype was a surprising discovery from what is otherwise a relatively well-explored region of the island, especially given its placement within a conspicuous and well-known group of plants. It resembles Cynanchum macrolobum at first glance, but differs in several consistent ways. The flowers are more distinctly cup-shaped, the stems are more strongly modeled with patches of black and waxy greenish white, and the plant takes on a vining habit rather than the more shrub-like form typical of macrolobum.
