Dissolution of Ipomoea series Anisomerae (Convolvulaceae)

Since the Anisomerae was proposed by House in 1908, all but three species have been moved into other parts of the genus. Morphological study now indicates that these three species should be placed elsewhere. Ipomoea anisomeres belongs in sect. Erpipomoea. Ipomoea squamosa and I. lindenii do not seem to he closely related to each other or to I. anisomeres. Thus, this series was polyphyletic. The species were originally grouped together because of convergent evolution in sepal inequality. Placement is proposed for all names included in 1908. The original species are now placed in Ipomoea sect. Eriospermum (ser. Batatas, ser. Eriospermum, ser. Mirandinae); Ipomoea sect Erpipomoea; Ipomoea sect. Exogonium; Ipomoea sect. Pharbitis ser. Tyrianthinae; to an Australian Ipomoea alliance (section unknown); and to the Old World genus Xenostegia. Several taxa confused with Ipomoea anisomeres and I. squamosa are discussed. Ipomoea pedicellaris is moved from ser. Setosae to sect. Erpipomoea. Nine species are described and illustrated, including the Hawaiian endemic Ipomoea tuboides (sect. Exogonium), and a new Panamanian endemic Ipomoea eremnobrocha D. F. Austin sp. nov. (sect. Eriospermum). A key is provided for identification. A new section and series are proposed for Ipomoea subg. Quamoclit sect. Tricolores J. A. McDonald, sect. nov., and Ipomoea subg. Quamoclit sect. Tricolores ser. Microsepalae D. F. Austin, comb. nov.