Kitagawia Pimenov.

Herbs perennial. Rootstock short, crown usually bearing remnant leaf sheaths. Stem finely striate, dichotomously branched above. Leaves petiolate; petioles sheathing. Umbels loosely compound, terminal and lateral; bracts numerous or absent; rays numerous or few; bracteoles numerous, rarely few or absent. Calyx teeth short or obsolete. Petals usually white, occasionally pinkish or purplish, rarely pale yellow, orbicular to obovate, with a narrow inflexed apex. Stylopodium low-conic. Fruit ellipsoid, oblong to suborbicular, dorsally compressed; dorsal ribs filiform, slightly prominent, lateral ribs thickened and narrowly winged, wings closely appressed to one another; vittae 1 to several in each furrow, 2 to several on commissure. Seed face plane or slightly concave. Carpophore bipartite.

The taxonomy of this widespread, heterogeneous genus has long been problematic. The broad circumscription of Peucedanum adopted here includes some 100–120 species from many parts of the Old World that are weakly united by basic (especially external) fruit structure. These fruit characters are undoubtedly the result of several lines of convergent evolution, and some authors prefer to recognize several segregate genera and reduce Peucedanum to only 8–10 Eurasian species based around the nomenclatural type, P. officinale Linnaeus. As the taxonomy of this genus is still unresolved (it is currently the focus of an international, multi-disciplinary study), a traditional treatment is adopted for the following account. Several Chinese taxa are represented by only a few herbarium specimens, a few (particularly species nos. 32–40) are recorded only from the type gatherings, and specific boundaries are not always clear. The Chinese members of this genus would benefit from a detailed revision augmented with new collections. The following key excludes P. lhasense (species no. 40) because there are insufficient data.

Between 100 and 200 species: Africa, Asia, Europe; 40 species (33 endemic) in China.

(Authors: She Menglan (佘孟兰 Sheh Meng-lan); Mark F. Watson)