Aristolochiaceae, comprising about 600 species, is a unique plant family containing aristolochic acids (AAs). In this study, we sequenced seven species of Aristolochia, and retrieved eleven chloroplast (cp) genomes published for comparative genomics analysis and phylogenetic constructions. The results show that the cp genomes had a typical quadripartite structure with conserved genome arrangement and moderate divergence. The cp genomes range from 159,308 bp to 160,520 bp in length and have a similar GC content of 38.5%–38.9%. A total number of 113 genes were identified, including 79 protein-coding genes, 30 tRNAs and four rRNAs. Although genomic structure and size were highly conserved, the IR-SC boundary regions were variable between these seven cp genomes. The trnH-GUG genes, are one of major differences between the plastomes of the two subgenera Siphisia and Aristolochia. We analyzed the features of nucleotide substitutions, distribution of repeat sequences and simple sequences repeats (SSRs), positive selections in the cp genomes, and identified 16 hotspot regions for genomes divergence that could be utilized as potential markers for phylogeny reconstruction. Phylogenetic relationships of the family Aristolochiaceae inferred from the 18 cp genome sequences were consistent and robust, using maximum parsimony (MP), maximum likelihood (ML), and Bayesian analysis (BI) methods.

From 2000 to 2019, 11,895 new names or new additions to the Chinese vascular flora were proposed by 4226 individuals (4086 articles and 140 books), as documented in the Chinese Plant Names Index (CPNI). During those 20 years, 4407 new taxa of vascular plants were described from China, including 7 new families, 132 new genera, 3543 new species, 68 new subspecies, 497 new varieties and 160 new forms. Additionally, 3562 new combinations and names at new rank and 306 new replacement names were also proposed. Among these various new names were 150 invalid names and 108 illegitimate names, including some that have not been resolved. Six hundred and forty three vascular plants were reported as new to China, while 2349 names were reduced to synonyms of 1406 taxa. The data show that the Chinese flora increased in size at the rate of about 200 taxa annually during those years. Despite the increased attention given to biodiversity in recent years, the evidence indicates that a large number of species in China have yet to be discovered. Further basic investigation of the Chinese flora is needed. Additionally, in the past two decades only 8.5% of the newly published species have been based on molecular evidence, but in the past five years such data have increased significantly, reaching about 20%. Molecular data will undoubtedly become increasingly significant in the discovery of new species in the coming years. Yunnan, Guangxi, Sichuan, Xizang and Taiwan were important sources of new discoveries, with more than 3300 new taxa and records from these five provinces. By area, Taiwan and Hainan, two islands in southern China, have the highest density of newly discovered species. Regional plant surveys are still needed, especially in areas in the southwest and on the southern islands.