The mitochondrial genome of the land snail Camaena cicatricosa (Müller, 1774) (Stylommatophora, Camaenidae): the first complete sequence in the family Camaenidae

Abstract

The complete mitochondrial (mt) genome of the snail Camaena cicatricosa (Müller, 1774) has been sequenced and annotated in this study. The entire circular genome is 13,843 bp in size and represents the first camaenid mt genome, with content of 31.9%A, 37.9%T, 13.5%C and 16.7%G. Gene content, codon usage and base organization show similarity to a great extent to the sequenced mt genome from Stylommatophora, whereas, gene order is different from them, especially the positions of tRNACys, tRNAPhe, COII, tRNAAsp, tRNAGly, tRNAHis and tRNATrp. All protein coding genes use standard initiation codons ATN except for COII with GTG as start signal. Conventional stop codons TAA and TAG have been assigned to all protein coding genes. All tRNA genes possess the typical clover leaf structure, but the TψC arm of tRNAAsp and dihydrouridine arm of tRNASer(AGN) only form a simple loop. Shorter intergenic spacers have been found in this mt genome. Phylogenetic study based on protein coding genes shows close relationship of Camaenidae and Bradybaenidae. The presented phylogeny is consistent with the monophyly of Stylommatophora.