The complete mitochondrial genomes of four Baikal molluscs from the endemic family Baicaliidae (Caenogastropoda: Truncatelloida)

Abstract

Abstract Here, we present the complete mitochondrial (mt) genomes of four members of the Baicaliidae Fisher, 1885, a truncatelloidean family that is endemic to Lake Baikal (East Siberia). The mt genomes are those of Korotnewia korotnevi (15,171 bp), Godlewskia godlewskii (15,224 bp), Baicalia turriformis (15,127) and Maackia herderiana (15,154 bp). All these mt genomes contain 13 protein-coding genes, 2 ribosomal RNA (rRNA) genes and 22 transfer RNA (tRNA) genes. We detected non-canonical base pairs in some of the tRNA genes and variable numbers of non-coding spacers; some tRNAs do not have a TψC loop. We found gene order to be highly conserved in these Lake Baikal species and similar to the majority of caenogastropod mt genomes available on GenBank. A position of the putative control region is delimited to the non-coding region between trnF and the cox3 gene. It contains the ‘GAA(A)nT’ motif at the 3′ end and is similar to the replication origin found in most Caenogastropoda studied to date. We also compared the evolutionary rates of different genes to evaluate their use in different kinds of population or phylogenetic studies of this group of gastropods.