Taxonomic Notes on Cimicifuga purpurea, Stat. Nov. (Ranunculaceae)

Examination of type specimens and other collections of Cimicifuga acerina f. purpurea and forma strigulosa revealed that they are not separable from one another but are very distinct from C. acerina and other related species of the genus in many morphological characters, including sepal color, stamen number, anther structure, and presence of cauline leaves. Therefore, these two formae are combined and recognized here as a distinct species, C. purpurea. The genus Cimicifuga L. (Ranunculaceae) consists of ca. 18 species (Tamura, 1966, 1990) that usually occupy shady, moist habitats in rich mountain woods. The species of Cimicifuga are distributed in temperate to cold temperate regions of the Northern Hemisphere including Europe, Asia, and North America, with the center of diversity in eastern Asia. They are readily distinguished by their large ternately compound leaves that are long-petioled, racemose or paniculate inflorescences bearing many small flowers, and follicular fruits with 4 to 15 seeds (Ramsey, 1965; Tamura, 1966, 1990). Hsiao (in Wang & Hsiao, 1965) described four formae of C. acerina (Siebold & Zuccarini) Tanaka from China on the basis of differences in leaf puhescence and sepal color; these include f. acerina, f. hispidula, f. purpurea, and f. strigulosa. During a comprehensive systematic study of the genus Cimicifuga, we examined the type specimens and other collections of forma purpurea and forma strigulosa and found that they are very distinct from C. acerina (= C. japonica (Thunberg) Sprengel; see Hara (1985)) in having purple sepals, five to eight stamens with dorsifixed and introrsely dehiscent anthers (Fig. 1A-C), somewhat elongated styles with narrowly capitate stigmas (Fig. 1D), and cauline leaves. Furthermore, the stamen number of forma purpurea and forma strigulosa is significantly lower than that of all other species in the genus, which usually have 20 to 70 stamens. In addition, anthers are usually basifixed and latrorsely dehiscent in other species of the genus. Although Hsiao (in Wang & Hsiao, 1965) stated that forma strigulosa differs from forma purpurea in having strigulose leaves, it does not seem to be consistently distinguishable by any characters other than leaf pubescence, which shows variation and some degree of overlap. Therefore, it can hardly be considered as distinct from forma purpurea, and we believe that they should be united. Based on the above observations, it is concluded that the appropriate taxonomic treatment regarding forma purpurea and forma strigulosa is to combine them and to raise the combined taxon to species rank. Since these names were published simultaneously by Hsiao (in Wang & Hsiao, 1965) and since their synonymy has not been previously recognized, we have selected the name forma purpurea (Article 11.5 of ICBN (Greuter et al., 1994)) as a basionym for this species, as the distinguishing characters mentioned above seem to be correlated with purple sepals. The necessary nomenclatural change, along with an expanded description, is provided here in advance of our monograph of the genus to make it available for use in the forthcoming paper on pollen morphology of the genus Cimicif-