Characterization of the complete mitochondrial genome of Notospermus geniculatus

In this study, the complete mitochondrial genome of Notospermus geniculatus, was recovered through Illumina sequencing data. This complete mitochondrial genome of N. geniculatus is 15,180 bp in length and has a base composition of A (14.4%), T (41.3%), C (14.6%), G (29.6%), demonstrating a bias of higher AT content (55.7%) than GC content (44.2%). The mitochondrial genome contains a typically conserved structure among Lineidae mitogenomes, encoding 13 protein-coding genes (PCGs), 23 transfer RNA genes (tRNA), 2 ribosomal RNA genes (12S rRNA and 16S rRNA), and a control region (D-loop region). All PCGs were located on the H-strand. ND4L gene and ND4 gene were overlapped by 6 bp. The whole mt genome of N. geniculatus and other Protostomia mitogenomes (17 species, in total) were used for phylogenetic analysis. The result indicated N. geniculatus has the closest relationship with Lineus viridis (FJ839919.1) and clustered within Heteronemertea Clade, which representing a distinct order.