(1244‐1246) Proposals to reject the names Trifolium agrarium, T. filiforme and T. procumbens (Leguminosae)

Abstract

The names Trifolium aureum Pollich 1777, T. campestre Schreb. 1804, T. dubium Sibth. 1794, and T. micranthum Viv. 1824 have for over half a century been in almost universal use for four related, widespread Eurasian and North African species belonging to T. sect. Chronosemium Ser. (Zohary & Heller, Gen. Trifolium. 1984). The protologues and, where designated, lectotypes of these names provide a clear and firm basis for their taxonomic application. However, they are threatened by three earlier names published in 1753 by Linnaeus in Species plantarum: T. agrarium, T. filiforme and T. procumbens. No formal designations of lectotypes could be traced for these names. Upon lectotypification, they would become senior taxonomic synonyms of up to three of the later names because their original material (at least that which is taxonomically determinable) belongs to the species currently known as T. aureum, T. campestre, T. dubium, and T. micranthum. No protection may be sought from Art. 57 of the Code since none of the Linnaean names has been widely and persistently used in a sense not including its type. They have simply fallen out of use, and only in a few isolated instances do they appear in the literature of the last 50 years as accepted names rather than synonyms. (For older usage of the names see the extensive discussion by Celakovsky in Osterr. Bot. Z. 22: 245-253. 1872, and the account by Gams in Hegi, Ill. Fl. Mitt.-Eur. 4: 1288-1294. 1923). Therefore, rejection of the three Linnaean names, rather than lectotypification, seems appropriate in order to avoid undesirable nomenclatural changes. All relevant original elements have been examined carefully in order to ascertain their taxonomic identities. The specimens among them mostly comprise good quality material, and nearly all could be determined satisfactorily. The illustrations are much more variable in quality, and few could be identified with any confidence. Trifolium aureum is distributed through much of Europe, extending into central Asia, and also occurs as an introduction in N. America, Australia and New Zealand. T campestre is more widespread, extending from Macaronesia through Europe and N. Africa to the western Himalayan region. It is also introduced in Ethiopia, Madagascar, the Cape region, N. America, Chile and New Zealand. T. dubium has a similar distribution to T. aureum but also occurs in South Africa, whereas T micranthum is restricted to Europe and N. Africa, extending eastwards to the Caucasus. Full distributions for all four species are mapped by Hulten & Fries (Atlas N. Eur. Vasc. PI. 2: 620-621. 1986).