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Chedrinae fish, which belong to Danionidae, have important ornamental, economic, and scientific value. At present, however, their mitogenomic features are unclear and their phylogenetic relationships remain controversial. In this study, we presented five new Chedrinae mitochondrial genomes (mitogenomes) and analyzed the conserved and variable mitogenomic characteristics of 17 Chedrinae fish. The gene composition and arrangement and secondary structure of transfer RNAs (tRNAs) were highly conserved among the Chedrinae mitogenomes. However, the length of the control region and base composition were variable. Interestingly, the mitogenome of Barilius barila was unusual, with lower A+T content in the first codon of protein-coding genes (PCGs) (47.32% versus average of 54.47%) and distinct pattern of codons per thousand codons (CDspT). Three Chedrinae fish had a long tandem repeat (>291 bp) in the 5'-end of the control region, which may increase their adaptability. In addition, tRNALys had notably larger DHU and TΨC loops than other tRNAs. The phylogenetic trees of the Chedrinae fish suggested that the Barilius genus was not a monophyletic group but could be divided into two main groups based on significant differences in A+T content. This study provides insights into the mitogenomic features and phylogenetic implications of Chedrinae fish, which should benefit their systematics and conservation. Chedrinae Bleeker 1863, also called Chedrina/Chedrini (Liao et al., 2011a), is one of the three subfamilies of Danionidae (Tang et al., 2010). Chedrinae fish usually inhabit turbulent rivers, mountain streams, and freshwater reservoirs. They are economically important in mountain regions and a valuable food source, as well as popular aquarium species due to their beautiful colors and patterns (Prabhu et al., 2020). Chedrinae fish are wildly distributed across Asia and Africa. The genus Raiamas is found on both continents, while other genera are found in Asia or Africa only, making them suitable models for studying the biogeographic history of freshwater systems. Due to habitat fragmentation, chemical fertilizer and pesticide use, and overfishing, Chedrinae and other mountain stream fish have become seriously threatened (Prabhu et al., 2020). Accurate species identification is essential for targeted protection; however, Chedrinae fish are cryptic, especially at the juvenile stage, and are thus difficult to distinguish morphologically. Mitochondrial genomes (mitogenomes) are widely used in species identification and molecular phylogenetics (Jiang et al., 2021; Yu et al., 2021). The gene arrangements of fish mitogenomes are generally conserved, whereas genome sequence length, base composition bias, and control region (CR) can show considerable species-level diversity (Yu et al., 2021). Although some complete Chedrinae mitogenomes have been sequenced and are available in the NCBI GenBank database, the mitogenomic characteristics of Chedrinae fish remain unclear. In addition, the phylogeny of Chedrinae fish is still controversial. In the current study, we sequenced five complete Chedrini mitogenomes and compared them with 12 other Chedrini to clarify the features of the Chedrinae mitogenomes. We also constructed the phylogenetic relationship of Chedrinae fish based on a 11 383 bp sequence matrix of 13 PCGs. The complete mitogenomes of five Chedrinae fish, including B. bernatziki (GenBank accession No. MW625809), B. barila (MW625806), B. pulchellus (MW625808), B. ardens (MW625805), and B. canarensis (MW625807), were first sequenced and annotated (Figure 1A; Supplementary Table S1), then compared with 12 previously reported Chedrinae mitogenomes (Supplementary Table S2). The A+T content,