Figure 1

Phylogenetic relationships among major gastropod lineages. Note that Heterobranchia additionally to Opisthobranchia and Pulmonata comprises some minor groups (Valvatoidea, Rissoelloidea, Architectonicoidea, and Pyramidelloidea). (A) Morphological phylogenies of Haszprunar [91] and Ponder and Lindberg [47]. (B) Molecular analysis based on genomic DNA by McArthur and Harasewych [37], and combined analysis of molecular and morphological data by Aktipis et al. [38]. (C) Molecular phylogeny based on mitochondrial genome arrangements by Grande et al. [39]; Note that neritimorph gastropods were not included in the analysis.