The complete mitogenome of the Roman snail Helix pomatia Linnaeus 1758 (Stylommatophora: Helicidae)

This study reports the complete mitochondrial sequence of the Roman snail, one of the largest terrestrial snails of Europe. Two specimens of Helix pomatia were sequenced, which had a sequence length of 14,070 and 14,072 base pairs. The mitogenome has the common metazoan makeup (13 protein-coding genes, two ribosomal RNAs, and 21 transfer RNAs) and the 'typical' Helicid gene order (Cytochrome Oxidase subunit III and tRNA-T translocated compared to other Helicoidea). All protein coding genes could be annotated with proper start and stop codons (no completion of stop codons by polyadenylation). The specimens have a sequence similarity of 99.0% (146 differences) and the average base composition is 29.7% A, 15.0% C, 17.9% G, and 37.4% T. Phylogenetic anlyses with available Helicid mitogenomes show Helicinae as monophyly and H. pomatia as the sister-group of (Cepaea nemoralis, Theba pisana, and Cornu aspersum).