The Mitochondrial Genome of the Springtail Semicerura bryophila (Collembola): New Data Call into Question the Relevance of the Subfamilies of the Isotomidae

<b>Background</b>: <i>Semicerura bryophila</i> Potapov & Sun, 2020 is a soil-dwelling springtail belonging to the family Isotomidae. The phylogenetic relationships among species of this group remain controversial due to a lack of molecular data. Therefore, in this study, we sequenced the mitochondrial genome of <i>S. bryophila</i>, analyzed the characterization of the mitochondrial genome, and investigated the phylogenetic relationships of Isotomidae. <b>Methods</b>: The mitochondrial genome of <i>S. bryophila</i> was sequenced and assembled. We analyzed the sequence length, nucleotide composition, and evolutionary relationships within the Isotomidae family, incorporating data from twelve previously published mitochondrial genomes. <b>Results</b>: The length of the <i>S. bryophila</i> mitogenome is 15,247 bp and comprises 13 protein-coding genes, 22 tRNAs, and two <i>rRNA</i>s, arranged in a typical order. Its base composition is as follows: A = 38.05%, T = 33.64%, G = 10.17%, and C = 15.03%. Phylogenetic analysis based on the mitogenome revealed that the monophyly of Isotomidae and the paraphyletic grouping of <i>Semicerura</i> and <i>Folsomotoma</i>, supporting their closer relationship with the subfamily Anurophorinae rather than to Isotominae. The analysis validated subfamily Anurophorinae, identified Pachyotominae as a part of Anurophorinae, and suggested that Isotominae is paraphyletic. <b>Conclusions</b>: The present study provides valuable mitochondrial information for the classification of <i>S. bryophila</i> and offers new insights into the taxonomic and evolutionary studies within the genus <i>Semicerura</i>.