ISI 2003-23. Cynanchum pachycladon Choux

An unusual member of this genus of milkweeds, it is named for its exceptionally succulent stems. It could just as well have been called Cynanchummacrophyllum”, as it also has unusually well-developed leaves for the genus. These are cordate (heart-shaped) and two to three inches long. When rubbed, they emit a curious musty aroma reminiscent of mouse. This smell is the same produced by the inflorescences of Peperomia graveolens, which in the latter may serve to attract fly pollinators. What purpose it serves the Cynanchum is unknown, except perhaps its rankness deters herbivores. Rooted cuts of HBG 89142, a plant collected Oct. 30, 1995, by Lavranos (30078), Barad, James, Kimnach & Linden in Didierea forest ca. 35 km. N of Tulear on the road to Morombe, Madagascar. $5.

Photo © 2003 by John N. Trager. Images may not be used elsewhere without permission.

Published in the Cactus and Succulent Journal, Vol. 75 (2), March - April, 2003