The genus Sanicula L. possesses many medically important plants, belonging to the family Apiaceae. It is one of the most taxonomically difficult taxa, largely due to the great variability in habit, foliage, flowers and fruits. Previous studies have mainly focused on the molecular studies of this genus, and the morphological research for this genus was limited, especially in the micromorphological research. In the current study, we newly obtained leaf materials from twenty-two Sanicula members, fruit and pollen materials from twenty Sanicula members and performed comprehensively micromorphological analyses for this complicated genus. The results of the leaf epidermis showed that the upper and lower epidermis were smooth and glabrous, and the cell shape was polygonal or irregular. The patterns of anticlinal wall were shallowly undulating, deeply undulating, subflat or flat. The cuticular membrane ornamentations were diverse, and some species had epidermal appendage. All Sanicula species observed the stomata in the lower epidermis, and only five species (S. rugulosa, S. elongata, S. hacquetioides, S. tienmuensis and S. elata) observed stomata in the upper epidermis, which can easily identify them from other Sanicula members. In addition, we found that the fruits scarcely compressed, and some fruits had their distinctive shape, such as the fruit shape of S. tienmuensis was subglobose, S. subgiraldii was broadly ovate and S. pengshuiensis was ellipsoid. All Sanicula taxa fruits surfaces were covered with prickles, bristles, protuberance, or tubercles, prickles were either long or short, uncinate or straight, rarely scale-like, ribs inconspicuous or slightly prominent, but the prickles/bristles/tubercles were different in shape, sparseness and arrangement. The vittae were distinct in S. rubriflora, S. chinensis, S. caerulescens, S. pengshuiensis, S. pauciflora, S. lamelligera, S. oviformis, S. flavovirens and S. elata, and the remaining taxa were obscure. These findings indicated that the fruits can clearly distinguish these Sanicula members. Furthermore, the micromorphological characteristics of pollen showed that the equatorial view included four shapes: ellipsoid, subrectangular, equatorially constricted and super-rectangular-equatorially constricted; and the polar view possessed four shapes: triangular, triangular–circular, suborbicular and trilobate circular. The germ furrow and the outer wall ornamentation of all Sanicula taxa were quite similar, indicating that the genus was a natural unit. In summary, our study promoted the improvement of a taxonomic system for the genus and also provided additional evidence for future taxonomic study of the genus Sanicula.

Pimpinella (Apiaceae) exhibits persistent taxonomic instability due to ambiguous morphological boundaries with its allies. We conducted phylogenetic analyses by integrating newly generated sequences with public NCBI datasets, including 166 plastome coding sequences (CDS) (44 new), 107 nrDNA operon sequences (67 new), 462 nrDNA internal transcribed spacer (ITS) sequences (62 new), and 199 rps16 and 153 rpl16 introns. These were complemented by a morphological study focusing on leaves, umbels, and especially mericarps from 32 Pimpinella taxa and allied species, to reassess the taxonomy of Pimpinella. Phylogenetic analysis resolved Pimpinella into seven clades, with the monophyletic type-containing group representing true Pimpinella and six additional clades phylogenetically embedded within allied genera. The considerable variation in morphological traits and plastome features supports the taxonomic re-evaluation. Consistent with molecular results, the type clade displays distinct morphological discontinuities, including a pubescent indumentum throughout, basal leaves that are predominantly simple, ternate, or 1-pinnate (rarely bipinnate), and fruits lacking persistent calyx teeth, with obscure ribs and pentagonal-rounded transverse sections. We propose reducing the circumscription of Pimpinella to exclude species from the six non-type clades and formally propose a new combination Pimpinella triradiata (H.Wolff) L.Y.Xiao & X.J.He, comb. nov. Overall, the taxonomy of Pimpinella is more complex than previously thought, and while this study enhances our understanding, further research is essential to address the remaining taxonomic challenges.