The complete mitochondrial genome of the file ramshorn snail Planorbella pilsbryi (Mollusca: Gastropoda: Hygrophila: Planorbidae)

Mitochondrial DNA B Resour. 2021 Oct 11;6(11):3181-3183. doi: 10.1080/23802359.2021.1975508. eCollection 2021.

Abstract

The file ramshorn snail Planorbella pilsbryi Baker, 1926 (Gastropoda: Hygrophila: Planorbidae) is a widespread herbivorous North American freshwater snail found in diverse habitats, including standing and moving water bodies. Genome skimming by Illumina sequencing allowed the assembly of a complete nuclear rRNA repeat sequence and a complete circular mitogenome of 13,720 bp from P. pilsbryi consisting of 75.3% AT nucleotides, 22 tRNAs, 13 protein-coding genes, 2 rRNAs and a control region in the typical order found in panpulmonate snails. Planorbella pilsbryi COXI features a rare TTG start codon while COXII, CYTB, ND2, ND3, and ND5 exhibit incomplete stop codons completed by the addition of 3' A residues to the mRNA. Phylogenetic reconstruction of mitochondrial protein-coding gene and rRNA sequences places P. pilsbryi as sister taxon to Planorbella duryi (Planorbidae) within family Planorbidae, which is consistent with previous phylogenetic hypotheses.

Keywords: Illumina sequencing; Planorbidae; mitogenomics; nuclear rRNA repeat; phylogeny.

Grants and funding

This work received support from NSERC under Grant RGPIN-2016-06012 and RGPIN-2014-05142 as well as from the University of Manitoba’s University Research Grants Program.