Molecular phylogeny of the Orthurethra (Panpulmonata: Stylommatophora)

Abstract

We have undertaken a molecular analysis of the Orthurethra, one of the major groups of stylommatophoran land snails and slugs. Approximately 4000 nucleotides of the rRNA gene cluster [5.8S, internal transcribed spacer 2 (ITS2) and almost the full-length large subunit (LSU; 28S) gene] were sequenced for 40 orthurethran genera belonging to 19 families. Our phylogeny recovers three well-supported clades within the Orthurethra; the Azecidae, Chondrinidae + Truncatellinidae, and a main clade comprising all remaining orthurethran families. The first division in the Orthurethra separates the Azecidae from all other orthurethran taxa. Of those families represented by more than one genus, the Achatinellidae, Azecidae, Cerastidae, Partulidae and Vertiginidae are recovered as strongly supported monophyletic units, whereas the Chondrinidae, Enidae, Pupillidae and Valloniidae are unsupported in the tree. Although there is relatively little support for the deep-level relationships among the main orthurethran groups, some groupings are strongly supported. The sister-group relationship of the Cochlicopidae with the Amastridae is strongly supported in our molecular analyses, and there is also some support for the grouping of the Orculidae with the Pyramidulidae, and the Draparnaudiidae with the Gastrocoptidae. The findings of our molecular analyses support dividing the Orthurethra into three superfamilies: the Azecoidea, Chondrinoidea and Pupilloidea.

Intercontinental dispersal and niche fidelity drive 50 million years of global diversification in Vertigo land snails

“…Brozzo et al., 2020; Neiber et al., 2022; Razkin et al., 2015) or featured less comprehensive sampling of included clades (e.g. de Weerd & Gittenberger, 2013; Saadi et al., 2021; Teasdale, 2017; Wade et al., 2006). In this context, our analysis of Vertigo diversification dynamics provides a unique opportunity to understand eco‐evolutionary drivers of land snail diversification at large spatio‐temporal scales.…”

“…Two scenarios for the upper age bound on the split between Vertigo and Nesopupa were implemented based on phylogenetic analyses of Panpulmonata with genome‐wide data (Teasdale, 2017). No representatives of Vertiginidae (to which Nesopupa and Vertigo belong) were included by Teasdale (2017), but the family belongs to Orthurethra (Nekola et al., 2023; Saadi et al., 2021) and the most basal divergence within Orthurethra was reconstructed to ~85 Ma (implemented as 87 Ma to account for uncertainty), whereas the age of the MRCA of Orthurethra and the divergent Clausilioidea was ~130 Ma. Therefore, we used 87 and 130 Ma, respectively, to constrain the maximum age of the split between Vertigo and Nesopupa .…”