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The number of chloroplast genomes of bamboos was growing, with an emphasis on Old World woody species.However, the chloroplast genomes of neotropical woody bamboos had rarely been studied.To pinpoint the pattern of chloroplast genome evolution within neotropical-paleotropical bamboos, we fully characterized one new chloroplast genome, for the woody bamboo Guadua angustifolia.The chloroplast genome of G.angustifolia was 135,332 bp long and was composed of an 82,840 bplarge single-copy (LSC) region, a 12,898 bp small single-copy (SSC) region, and a pair of 19,797 bp inverted repeats (IRs).Comparative analyses revealed marked conservation of gene contents and sequence evolutionary rates between neotropical and paleotropical woody bamboos.The neotropical herbaceous bamboo differed from woody bamboos in IR/SSC boundary due to slightly contracted IR and faster substitution rate.The chloroplast genome of G.angustifolia was similar in size to that of neotropical herbaceous bamboo but, notably, was ~3k bp smaller than that of paleotropical woody bamboos.Dissimilarities in genome size were correlated with various lengths of intergenic spacers caused by large-fragment insertion and deletion.Phylogenomic analyses of 53 taxa yielded an identical tree topology as in preceding studies.Divergence time estimation suggested that most genera of bamboos diverged in the Miocene and that speciation events of extant species happened in or after the Pliocene.