J. Jpn. Bot. 88: 166–175 (2013) New Combinations in North American Desmodium (Leguminosae: Tribe Desmodieae) Hiroyoshi OHASHI Herbarium, Botanical Garden, Tohoku University, Sendai, 980-0862 JAPAN E-mail:
[email protected] (Accepted on May 11, 2013) Three species groups in Desmodium of North America: D. ciliare group, D. paniculatum group and D. procumbens group are revised for Flora of North America. Each of them is treated as a single species containing one or two varieties. The following four new combinations are published: D. marilandicum var. ciliare (Willd.) H. Ohashi, D. marilandicum var. lancifolium (Fernald & B. G. Schub.) H. Ohashi, D. paniculatum var. fernaldii (B. G. Schub.) H. Ohashi, and D. procumbens var. neomexicanum (A. Gray) H. Ohashi. Desmodium obtusum (Willd.) DC. is regarded to be a synonym of D. marilandicum var. lancifolium; D. glabellum (Michx.) DC. and D. perplexum B.G. Schub. to be synonyms of D. paniculatum; and D. procumbens var. exiguum (A. Gray) B. G. Schub. to be a synonym of D. procumbens var. procumbens. Key words: Desmodium, Fabaceae, Leguminosae, new combinations, North America. Recently, Desmodium of North America can at least identify it with the group.” Under has been the subject of much study, notably by this framework, Isely recognized D. ciliare Schubert (1940, 1950a, 1950b, 1970) and Isely (Willd.) DC., D. paniculatum (L.) DC. and D. (1983, 1990, 1998). “Desmodium traditionally procumbens (Mill.) Hitchc., along with each is considered a ‘difficult’ genus” (Isely 1990, p. of their related taxa, as species groups. The 163). Isely (1990) further stated that Desmodium difficulty in classifying these groups is, however, contains “groups of species whose taxonomy not satisfactorily solved by this approach.