Taxonomic Revision Of Paederia In China

There are 31 species of Paederia in the world,most of which are distributed in the tropical and subtropical regions of Asia and Africa,and have high medicinal value.China is an important place of origin of the Paederia and a key area for the study of phylogeny of the Paederia.At present,there are taxonomic problems such as uncertain species number and unclear boundaries in the Paederia.In this study,the variation law and variation range of various traits in the genus were re-examined,and the leaf epidermal micromorphology,pollinology,and molecular systematics were comprehensively revised in China.The main conclusions are as follows:(1)Among the macromorphological traits,the characteristics of indument type,inflorescence type,calyx lobe,corolla morphological fruit traits and seed morphology had important classification value.The same species(even in the same population)in different geographical distributions and habitats showed great differences in leaf type,indument,flower color,corolla length and other traits.(2)Microscopic observation of the leaf epidermis micromorphology of nine species and one variety of the Chinese genus showed that the shape of the leaf epidermal cells of this plant was mostly irregular,the stomatal apparatus was distributed in the epidermis,and the basic type of stomatal apparatus was flat type,which belonged to the mesogenous origin.The stomatal index varies greatly between different species,and the smallest is the P.cavaleriei and the P.pertomentosa,stomatal index 14.29,the largest is the P.scandens var.tomentosa,stomatal index 60.(3)The pollen materials of 7 species and 1 variant of Paederia were collected for pollenological research,and the results showed that the pollen of Paederia were all single grains,symmetrical radiation,and belonged to small and medium-sized pollen,among which P.yunnanensis pollen grain is the smallest,with an average equatorial axis length of 21.74 μm,and the P.scandens var.tomentosa is the largest,with an average equatorial axis length of 28.54μm.The pollen shape is mainly spherical or nearly spherical,with 3 germination grooves,and the surface decoration is mainly reticulated or spiny,such as P.stenophylla is spiny-shaped,P.foetida is reticulated.(4)The results of molecular systematics analysis do not support the merger of P.stenophylla,P.scandens var.tomentosa and P.foetida.P.stenophylla and P.scandens var.tomentosa each form a separate branch,which is obviously different from P.foetida.P.cavaleriei and P.stenobotrya formed a cross-sectional clade that received a high support rate in favor of merging the two.In addition,the analysis results also provide molecular data and references for the treatment of some morphologically similar and controversial species,such as the relationship between P.laxiflora and P.foetida.(5)After field investigation and specimen review,P.cruddasiana was finally found in the HITBC and PE,which confirmed that this species was mainly distributed in the Xishuangbanna area of southern Yunnan,China.(6)Based on various studies,it was confirmed that there were 10 species and 1 varieties of Paederia in Chinese.Among them,the P.stenobotrya was treated as a synonym of the P.cavaleriei,the P.scandens var.tomentosa was promoted as a species,and the P.stenophylla was restored as an independent species.The P.laxiflora as a variant of the P.foetida.Finally,the taxonomic revision of the Paederia in Chinese was completed.