In this study, we critically revised and updated the checklist of native vascular plants of Mongolia. The checklist comprises 3,041 native vascular plant taxa (2,835 species and 206 infraspecific species) from 653 genera and 111 families, including 7 lycophytes, 41 ferns, 21 gymnosperms, and 2,972 angiosperms. In the angiosperms, we identified the 14 families with the greatest species richness, ranging from 50 to 456 taxa. Species endemism is also noted here; 102 taxa are endemic to Mongolia, and 275 taxa are sub-endemic that co-occur in adjacent countries. Since 2014, a total of 14 taxa have been described new to science based on morphological evidences. Moreover, five genera and 74 taxa were newly added to the flora of Mongolia. Based on our critical revisions, names of three families, 21 genera, and 230 species have been changed in comparison to the previous checklist, “Conspectus of the vascular plants of Mongolia” (2014).

Hybridization is an important evolutionary process that results in increased plant diversity. Flowering Prunus includes popular cherry species that are appreciated worldwide for their flowers. The ornamental characteristics were acquired both naturally and through artificially hybridizing species with heterozygous genomes. Therefore, the genome of hybrid flowering Prunus presents important challenges both in plant genomics and evolutionary biology. We use long reads to sequence and analyze the highly heterozygous genome of wild Prunus yedoensis. The genome assembly covers > 93% of the gene space; annotation identified 41,294 protein-coding genes. Comparative analysis of the genome with 16 accessions of six related taxa shows that 41% of the genes were assigned into the maternal or paternal state. This indicates that wild P. yedoensis is an F1 hybrid originating from a cross between maternal P. pendula f. ascendens and paternal P. jamasakura, and it can be clearly distinguished from its confusing taxon, Yoshino cherry. A focused analysis of the S-locus haplotypes of closely related taxa distributed in a sympatric natural habitat suggests that reduced restriction of inter-specific hybridization due to strong gametophytic self-incompatibility is likely to promote complex hybridization of wild Prunus species and the development of a hybrid swarm. We report the draft genome assembly of a natural hybrid Prunus species using long-read sequencing and sequence phasing. Based on a comprehensive comparative genome analysis with related taxa, it appears that cross-species hybridization in sympatric habitats is an ongoing process that facilitates the diversification of flowering Prunus.

Following recent taxonomic, distributional, and nomenclatural revisions, an updated checklist of endemic plants on the Korean Peninsula is needed. This study provides an updated checklist of vascular plants endemic to the Korean Peninsula and describes their distribution within administrative provinces. The revised checklist includes 373 endemic taxa (304 species, six subspecies, 49 varieties, and 14 nothospecies) from 179 genera and 64 families, representing 9.5% of the total native flora of the Korean Peninsula. Asteraceae (41 taxa), Ranunculaceae (29 taxa), Liliaceae s.l. (24 taxa), and Rosaceae (22 taxa) were the most widely represented families. Compared with the most recent checklist published in 2017, 39 taxa were excluded from the checklist; one taxon was excluded because it did not have a valid published name, seven taxa were excluded because their natural habitats extended to neighboring countries, four taxa were excluded because they were treated as a rank form, and 27 taxa were excluded because they had been identified as heterotypic synonyms of taxa distributed outside of the Korean Peninsula. Fifty-two new taxa were included based on the literature. This checklist will help to focus conservation efforts and provide a framework for research, protection, and policy implementation related to these endemic taxa.

Sophora koreensis Nakai, an endemic species distributed only in the Korean Peninsula, is of great geographical, economic, and taxonomic importance. Although its complete chloroplast (cp) genome sequence has been reported, its mitochondrial (mt) genome sequence has not yet been studied. Therefore, in this study, we aimed to investigate its mt genome sequence and compare it with those reported for other Fabaceae species. Total genomic DNA was extracted from fresh S. koreensis leaves collected from natural habitats in Gangwon-do Province, South Korea. This was followed by polymerase chain reaction (PCR) amplification of cpDNA insertions in the mt genome and the detection of microsatellites and dispersed repeats in the cp and mt genomes. Finally, the cp and mt genomes of S. koreensis were compared with those reported for other Fabaceae species. The cp sequence of S. koreensis showed identical gene orders and contents as those previously reported. Only six substitutions and one deletion were detected with 99 % homology. Conversely, the complete mt genome sequence, which was 517,845 bp in length and encoded 61 genes, including 43 protein-coding, 15 transfer RNAs, and 3 ribosomal RNA genes, was considerably different from that of S. japonica in terms of gene order and composition. Further, the mt genome of S. koreensis included ca. 7 and 3 kb insertions, representing an intracellular gene transfer (IGT) event, and the regions with these insertions were determined to be originally present in the cp genome. This IGT event was also confirmed via PCR amplification. IGT events can be induced via biological gene expression control or the use of repetitive sequences, and they provide important insights into the evolutionary lineage of S. koreensis. However, further studies are needed to clarify the gene transfer mechanisms between the two organelles.

Semiaquilegia quelpaertensis sp. nov., a new species belonging to the family Ranunculaceae, from Hallasan National Park in Jeju-do, Republic of Korea, is described and illustrated. The new species is similar to Semiaquilegia adoxoides (DC.) Makino, but can be readily distinguished by a thick underground stem, shallowly lobed leaflets, larger flowers, (4–)6 staminodes and conspicuously rugose tuberculate seed surface.