Characterization of the complete mitochondrial genome sequence of Neoscona scylla and phylogenetic analysis

The complete mitochondrial genome of the orb-weaving spider Neoscona scylla was characterized in this study. The circular molecule is 14,092 bp in length (GenBank accession no. MK086023), containing 13 protein-coding genes (PCGs), two ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes, and a control region. The nucleotide composition is asymmetric (35.27% A, 9.82% C, 15.55% G, 39.36% T), with an overall A + T content of 74.63%. The gene arrangement of N. scylla is identical to that observed in other spiders. Nine PCGs are initiated with typical ATN start codons, three genes (cox2, cox3, and nad6) begin with TTG, and cox1 use TTA as initiation codon. Twelve PCGs stop with complete termination codon TAA and TAG, while nad3 uses incomplete termination codon (T). Twenty-five reading frame overlaps and five intergenic regions are found in the mitogenome of N. scylla. Seven tRNAs lose T psi C arm stems, whereas three lack the dihydrouracil (DHU) arm. The phylogenetic relationships based on 13 PCGs show that N. scylla clusters closest to 5 species of Araneidae.