Cyrtomium falcatum is a popular ornamental fern cultivated worldwide. Native to the Korean Peninsula, Japan, and Dokdo Island in the Sea of Japan, it is the only fern present on Dokdo Island. We isolated and characterized the chloroplast (cp) genome of
C. falcatum
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Cyrtomium falcatum is a popular ornamental fern cultivated worldwide. Native to the Korean Peninsula, Japan, and Dokdo Island in the Sea of Japan, it is the only fern present on Dokdo Island. We isolated and characterized the chloroplast (cp) genome of
C. falcatum, and compared it with those of closely related species. The genes
trnV-GAC and
trnV-GAU were found to be present within the cp genome of
C. falcatum, whereas
trnP-GGG and
rpl21 were lacking. Moreover, cp genomes of
Cyrtomium devexiscapulae and
Adiantum capillus-veneris lack
trnP-GGG and
rpl21, suggesting these are not conserved among angiosperm cp genomes. The deletion of
trnR-UCG,
trnR-CCG, and
trnSeC in the cp genomes of
C. falcatum and other eupolypod ferns indicates these genes are restricted to tree ferns, non-core leptosporangiates, and basal ferns. The
C. falcatum cp genome also encoded
ndhF and
rps7, with GUG start codons that were only conserved in polypod ferns, and it shares two significant inversions with other ferns, including a minor inversion of the
trnD-GUC region and an approximate 3 kb inversion of the
trnG-trnT region. Phylogenetic analyses showed that
Equisetum was found to be a sister clade to Psilotales-Ophioglossales with a 100% bootstrap (BS) value. The sister relationship between Pteridaceae and eupolypods was also strongly supported by a 100% BS, but Bayesian molecular clock analyses suggested that
C. falcatum diversified in the mid-Paleogene period (45.15 ± 4.93 million years ago) and might have moved from Eurasia to Dokdo Island.
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