Phylogenetic relationships among superfamilies of Neritimorpha (Mollusca: Gastropoda)

Despite the extraordinary morphological and ecological diversity of Neritimorpha, few studies have focused on the phylogenetic relationships of this lineage of gastropods, which includes four extant super families: Neritopsoidea, Hydrocenoidea, Helicinoidea, and Neritoidea. Here, the nucleotide sequences of the complete mitochondria] genomes of Georissa bangueyensis (Hydrocenoidea), Neritina usnea (Neritoidea), and Pleuropoma jana (Helicinoidea) and the nearly complete mt genomes of Titiscania sp. (Neritopsoidea) and Theodoxus fluviatilis (Neritoidea) were determined. Phylogenetic reconstructions using probabilistic methods were based on mitochondria] (13 protein coding genes and two ribosomal rRNA genes), nuclear (partial 28S rRNA, 18S rRNA, actin, and histone H3 genes) and combined sequence data sets. All phylogenetic analyses except one converged on a single, highly supported tree in which Neritopsoidea was recovered as the sister group of a Glade including Helicinoidea as the sister group of Hydrocenoidea and Neritoidea. This topology agrees with the fossil record and supports at least three independent invasions of land by neritimorph snails. The mitochondria] genomes of Titiscania sp., G. bangueyensis, N. usnea, and T. fluviatilis share the same gene organization previously described for Nerita mt genomes whereas that of P. jana has undergone major rearrangements. We sequenced about half of the mitochondria] genome of another species of Helicinoidea, Viana regina, and confirmed that this species shares the highly derived gene order of P. jana. (C) 2016 Elsevier Inc. All rights reserved.