The original description of Ipomoea sphenophylla by Urban in 1908, based upon a fruiting specimen, did not include a description of the flowers. The holotype was subsequently lost and plants in flower were recol- lected in 1994; a neotype was then designated by Howard and McDonald in 1995. An amended description of the species was also supplied, detailing the characteristics of the cotyledons, a swollen root system, and dimorphic flowers. The flowers were described as including a more common morph with a normal funnelform corolla, and an abnormal morph having a 3–5 polypetalous corolla. Presently, both morphs occur together on one sterile indi- vidual that is located in the area where the neotype was collected. We have examined approximately 150 addi- tional plants, and all contain funnelform flowers. The polypetalous morphology is therefore atypical of Ipomoea sphenophylla. The species description is emended and the reference to polypetalous flowers is removed.