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Abstract Background Sinosenecio B. Nordenstam (Asteraceae) currently comprises 44 species. To investigate the interspecific relationship, several chloroplast markers, including ndhC-trnV, rpl32-trnL, matK, and rbcL, are used to analyze the phylogeny of Sinosenecio. However, the chloroplast genomes of this genus have not been thoroughly investigated. We sequenced and assembled the Sinosenecio albonervius chloroplast genome for the first time. A detailed comparative analysis was performed in this study using the previously reported chloroplast genomes of three Sinosenecio species. Results The results showed that the chloroplast genomes of four Sinosenecio species exhibit a typical quadripartite structure. There are equal numbers of total genes, protein-coding genes and RNA genes among the annotated genomes. Per genome, 49–56 simple sequence repeats and 99 repeat sequences were identified. Thirty codons were identified as RSCU values greater than 1 in the chloroplast genome of S. albonervius based on 54 protein-coding genes, indicating that they showed biased usage. Among 18 protein-coding genes, 46 potential RNA editing sites were discovered. By comparing these chloroplast genomes' structures, inverted repeat regions and coding regions were more conserved than single-copy and non-coding regions. The junctions among inverted repeat and single-copy regions showed slight difference. Several hot spots of genomic divergence were detected, which can be used as new DNA barcodes for species identification. Phylogenetic analysis of the whole chloroplast genome showed that the four Sinosenecio species have close interspecific relationships. Conclusions The complete chloroplast genome of Sinosenecio albonervius was revealed in this study, which included a comparison of Sinosenecio chloroplast genome structure, variation, and phylogenetic analysis for related species. These will help future research on Sinosenecio taxonomy, identification, origin, and evolution to some extent.

Corydalis microflora and C. lidenii are recognised as separate species in “Flora of China” and the latest plant list. However, based on the examination of type specimens and field investigations, C. lidenii is shown to be conspecific with C. microflora. As a result, C. lidenii is synonymised with C. microflora in this study.

A new species of Acanthaceae, Strobilanthes sunhangii, is described from Mêdog County, Tibet, China. Morphologically, the new species is closely similar to S. medogensis and S. divaricata, but S. sunhangii differs in having glabrous stems, longer spikes, glabrous rachis, double curved corolla and glabrous calyx, different stamens and style.

Saxifraga sunhangiana, a new species of the genus Saxifraga sect. Irregulares (Saxifragaceae) from Gansu, China, is described and illustrated. This species is distinguishable by its abaxial leaf surface with singularly long white villous hairs and rather long rhizomes. Morphological and molecular data indicate that S. sunhangiana belongs to S. sect. Irregulares, and closely related to S. rufescens. The new species differs from S. rufescens by its terminal flower with two elongated, fusiform-lanceolate petals and leaves with glabrous petiole. [ABSTRACT FROM AUTHOR]