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The Sturnidae family comprises 123 recognized species in 35 genera. The taxa Mimidae and Buphagidae were formerly treated as subfamilies within Sturnidae. The phylogenetic relationships among the Sturnidae and related taxa (Sturnidae sensu lato) remain unresolved due to high rates of morphological change and concomitant morphological homoplasy. This study presents five new mitogenomes of Sturnidae sensu lato and comprehensive mitogenomic analyses. The investigated mitogenomes exhibit an identical gene composition of 37 genes—including 13 protein-coding genes (PCGs), 2 rRNA genes, and 22 tRNA genes—and one control region (CR). The most important finding of this study is drawn from CAM analyses. The surprisingly unique motifs for each species provide a new direction for the molecular species identification of avian. Furthermore, the pervasiveness of the natural selection of PCGs is found in all examined species when analyzing their nucleotide composition and codon usage. We also determine the structures of mt-tRNA, mt-rRNA, and CR structures of Sturnidae sensu lato. Lastly, our phylogenetic analyses not only well support the monophyly of Sturnidae, Mimidae, and Buphagidae, but also define nine stable subclades. Taken together, our findings will enable the further elucidation of the evolutionary relationships within Sturnidae sensu lato.

The genus Crassula is the second-largest genus in the family Crassulaceae, with about 200 species. As an acknowledged super-barcode, plastomes have been extensively utilized for plant evolutionary studies. Here, we first report 10 new plastomes of Crassula. We further focused on the structural characterizations, codon usage, aversion patterns, and evolutionary rates of plastomes. The IR junction patterns—IRb had 110 bp expansion to rps19—were conservative among Crassula species. Interestingly, we found the codon usage patterns of matK gene in Crassula species are unique among Crassulaceae species with elevated ENC values. Furthermore, subgenus Crassula species have specific GC-biases in the matK gene. In addition, the codon aversion motifs from matK, pafI, and rpl22 contained phylogenetic implications within Crassula. The evolutionary rates analyses indicated all plastid genes of Crassulaceae were under the purifying selection. Among plastid genes, ycf1 and ycf2 were the most rapidly evolving genes, whereas psaC was the most conserved gene. Additionally, our phylogenetic analyses strongly supported that Crassula is sister to all other Crassulaceae species. Our findings will be useful for further evolutionary studies within the Crassula and Crassulaceae.