(1526) Proposal to conserve the name Thalictrum foetidum (Ranunculaceae) with a conserved type

Abstract

The polynomials given by Linnaeus in the protologue of T foetidum in Species Plantarum relate to two taxa as understood today: caule filiformi ramosissimo in paniculam disperso subjectis foliolis cited from Hortus Cliffortianus and the works of van Royen and Sauvages refer to T minus L. subsp. saxatile DC. ex Ces., a taxon occurring in N Africa, S and W Europe, whereas minimum foetidissimum from the works of Bauhin, Morison and Plukenet are applicable to the species currently called T foetidum, which is widely distributed in Europe and Asia. Of the localities given in the protologue, Monspelii probably refers to the former, and Vallesia, Helvetia to the latter. The distribution of the two taxa overlaps in several European mountain ranges, such as the Pyrenees and the Alps. Because of the similarity of many populations the percentage of misidentified specimens in European herbaria is quite high. Hence, it is hardly surprising that Linnaeus adopted a taxonomic concept that combined the two taxa. In the context of the lectotypification of Linnaean generic names Riedl (in Jarvis, Taxon 41: 574. 1992) designated the specimen herb. Clifford 227, Thalictrum 5, BM as the type of Thalictrum foetidum. This choice was followed by Jarvis & al. (Regnum Veg. 127: 93. 1993). On this basis Tfoetidum should apply to the taxon currently known as T minus. However, the application of the name T foetidum has been stabilized since the early 19th century. Candolle (Fl. frang., ed. 3, 5: 633. 1815) was the first author to publish specific epithets for the plants closely related to T minus L.: T saxatile and T pubescens (both illegitimate homonyms). Since then the separation of T foetidum and these other taxa has not been doubted. According to the results of a recently published revision (Hand, Bot. Naturschutz Hessen, Beiheft 9. 2001) these other taxa, widel distributed in the Mediterranean area and W Europe, should be united as T minus subsp. saxatile, a polyploid taxon characterized by, for example, more or less symmetric achenes and glabrous or glandular hairy leaflets. For 200 years all important floras or treatments of the genus Thalictrum have applied the Linnaean name T foetidum to a diploid taxon (2n = 14) characterized by st ngly asymmetric, laterally flattened achenes and, in m st cases, a mixed indumentum of short, glandular and ong, eglandular hairs (e.g., Adler & al., Exkurs.fl. Osterr.: 288. 1994; Akeroyd in Tutin & al. (eds.), Fl. Eur., ed. 2, 1: 291. 1993; Davis & al. in Davis (ed.), Fl. Turkey 1: 201. 1965; Friesen in Malyshev & Peshkova (eds.), Fl. Sibiri 6: 202. 1993; Hess & al., Fl. Schweiz, ed. 2, 2: 44. 1977; Lecoyer, Bull. Soc. Roy. Bot. Belgique 24: 181. 1885; Osva'ilovi in Hejny & Slavik (eds.), Kvet. CSR 1: 460. 1988; Pignatti, Fl. Ital. 1: 337. 1982; Riedl in Rechinger (ed.), Fl. Iran. 171: 122. 1992; Wang & Wang in Agenda Acad. Sin. (ed.), Fl. Reipubl. Popul. Sin. 27: 580. 1979). The taxonomic confusion of the plants of S. Spain has already been clarified by Garcia Adai & al. (in Anales Jard. Bot. Madrid 52: 214-216. 1995). As already mentioned, the re-examined type in the Clifford herbarium selected earlier by Riedl proved to be T minus. This fragmentary specimen, comprising only the upper parts of a flowering stem with some leaflets covered by short, glandular hairs, belongs to the subspecies cited above. Whilst formally correct under Article 9, this choice of the type would lead to much nomenclatural and taxonomic confusion. By accepting it, T foetidum in the current and traditional sense must be replaced by T saxatile Vill. (Hist. P1. Dauphine 3: 714. 1789, non DC.), the next available name which has not been in use since the end