Musa (family Musaceae) is monocotyledonous plants in order Zingiberales, which grows in tropical and subtropical regions. It is one of the most important tropical fruit trees in the world. Herein, we used next-generation sequencing technology to assemble and perform in-depth analysis of the chloroplast genome of nine new Musa plants for the first time, including genome structure, GC content, repeat structure, codon usage, nucleotide diversity and etc. The entire length of the Musa chloroplast genome ranged from 167,975 to 172,653 bp, including 113 distinct genes comprising 79 protein-coding genes, 30 transfer RNA (tRNA) genes and four ribosomal RNA (rRNA) genes. In comparative analysis, we found that the contraction and expansion of the inverted repeat (IR) regions resulted in the doubling of the rps19 gene. The several non-coding sites (psbI–atpA, atpH–atpI, rpoB–petN, psbM–psbD, ndhf–rpl32, and ndhG–ndhI) and three genes (ycf1, ycf2, and accD) showed significant variation, indicating that they have the potential of molecular markers. Phylogenetic analysis based on the complete chloroplast genome and coding sequences of 77 protein-coding genes confirmed that Musa can be mainly divided into two groups. These genomic sequences provide molecular foundation for the development and utilization of Musa plants resources. This result may contribute to the understanding of the evolution pattern, phylogenetic relationships as well as classification of Musa plants.

Background: Flowering plants (angiosperms) dominate most global ecosystems today, but their rapid Cretaceous diversi cation has remained poorly understood ever since Darwin referred to it as an 'abominable mystery'. Although numerous Cretaceous fossil owers have been discovered in recent years, most are represented by incomplete charcoali ed fragments that do not preserve delicate structures such as complete petals and surface textures, which means that their similarity to living forms is often di cult to discern. The scarcity of information about the ecology of early angiosperms makes it di cult to test hypotheses about the drivers of their diversi cation. Among other factors, frequent res in the Cretaceous have been postulated as having possibly facilitated the rise of angiosperms. However, to date no early fossil angiosperms displaying re-adapted traits have been known, making the role of re in shaping Cretaceous oras uncertain.Results: We report the discovery of two exquisitely preserved fossil ower species, one identical to the in orescences of the extant crown eudicot genus Phylica and the other recovered as a sister group to Phylica, both preserved as inclusions in Cretaceous amber from northern Myanmar (~99 Ma). These specialized ower structures, named Phylica piloburmensis sp. nov. and Eophylica priscastellata gen. et sp. nov., were adapted to surviving frequent wild res, providing the earliest evidence of re-resistance in angiosperms. The fossils suggest that re was a signi cant selective force in Cretaceous angiosperm oras and that adaptations to re resistance in some eudicot clades have been conserved for at least 99 Ma. This morphological stasis encompasses a range of oral characters, including the production of 'pseudo-owers', and characteristic fruit and pollen architecture. Given its morphological distinctiveness,

Macadamia tetraphylla (Proteaceae) is one of the two macadamia plants that are edible and of cultivated value. Only two chloroplast genomes were reported in Proteaceae so far. In this study, we report the complete chloroplast genome sequence of M. tetraphylla, which is the third reported chloroplast genome in Proteaceae. The chloroplast genome is 159,195 bp long and includes 113 genes. Its LSC, SSC and IR regions are 87,951, 18,748 and 26,248 bp long, respectively. Phylogenetic analysis indicates that M. tetraphylla was clustered with other two species of Proteaceae, the M. integrifoia and M. ternifolia.

Thalictrum viscosum W.T.Wang & S.H.Wang, 1979 is a flowering plant species in family Ranunculaceae that is endemic to Yunnan province of China. To facilitate genetic study of T. viscosum , we de novo assembled and annotated the complete chloroplast (cp) genome of T. viscosum for the first time. The total length of the cp genome of T. viscosum was 155,984 bp, with a GC content of 38.4%. The T. viscosum cp genome had a typical quadripartite structure with a large single-copy region of 85,339 bp, a small single-copy region of 17,656 bp, and a pair of inverted repeat regions of 26,495 bp. The cp genome consisted of 133 genes, including 87 protein-coding genes, 38 transfer RNA genes, and eight ribosomal RNA genes. We performed phylogenetic analysis of T. viscosum with the maximum-likelihood phylogenetic tree and indicated that T. viscosum was closely related to T. cirrhosum and T. foeniculaceum.

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