As a consequence of the recently established polyphyly of American Cynanchum (Apocynaceae - Asclepiadoideae), the former section Macbridea is analyzed in detail using molecular, karyological and morphological data.  Three of the five species, C. angustifolium, C. peninsulare and C. utahense, are transferred to Funastrum: F. angustifolium, F. peninsulare and F. utahense.  The remaining two species, C. grisebachii and C. wrightianum are known from the type only and it is suggested to cite them as "Cynanchum" grisebachii and "C." wrightianum until analyzable material becomes available.

Keywords: Cynanchum, Funastrum, Karyology, Molecular systematics, Morphology, trnT-L spacer, trnL intron, trnL-F spacer, Apocynaceae, Asclepiadoideae